---------------------------------------------------------- KIS-List Digest Archive --- Total Messages Posted Mon 01/14/13: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 09:27 AM - Re: KIS TR-1 Airfoil (Propellerjan) 2. 12:43 PM - Re: KIS TR-1 Airfoil (Mark Kettering) 3. 01:37 PM - Re: KIS TR-1 Airfoil (Scott Stearns) 4. 05:49 PM - Re: KIS TR-1 Airfoil (Mark Kettering) 5. 06:09 PM - Re: KIS TR-1 Airfoil (Flyinisfun@aol.com) 6. 07:10 PM - Re: KIS TR-1 Airfoil (Scott Stearns) 7. 07:47 PM - Re: KIS TR-1 Airfoil (Scott Stearns) 8. 07:53 PM - Re: KIS TR-1 Airfoil (Flyinisfun@aol.com) ________________________________ Message 1 _____________________________________ Time: 09:27:08 AM PST US Subject: KIS-List: Re: KIS TR-1 Airfoil From: "Propellerjan" I put all data in from the KIS, with airfoil data, and the KIS handbook from Norway using the original size of H-stab and elevator, and Hans Christan's forward and most after CG load example into Neil Willford's excellent excel spreads. the CG ended up exactly the same as in Hans Christan's book, good work both of them. with 5" stick travel (what is original layout?) I got little over the 4,4 lb/g recommended as minimum, for this 4,4G aircraft with sticks. the most forward CG with this setup with flaps was aerodynamically said to be right at the forward limit 18% MAC, in ground effect and with flaps, so no margins there. All dimensions for the H-stab and elevator is at the lower recommended numbers, both the Tail volume Nr's with Fwd and rear CG Tv=0,49-0,50 ( 0,5 is recommended for single seat or 2-seat without flap, 0,7 for four seat, and 0,6 for 2-seat with flaps) I then increased the H-tail to 17 sq/ft and elevator percent to 40% of the tail chord, this moved the most forward CG limit possible to 16,2% MAC in ground effect and with flaps, and stick force gradient up to about 6 lb/g Aileron stick force with +- 12 deg. was something like 36 lb, also with 5" travel each way. sounds heavy to me, but is what we can expect from those plates. So much for theory, but it agree with what you guys learned from flying the KIS. and the agreement was highly surprising but rewarding it need bigger elevator and tail volume. Anyone have the original unmodified stick travel (at top) and yours if modified ? Jan Carlsson www.jcpropellerdesign.com -------- www.jcpropellerdesign.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=392259#392259 ________________________________ Message 2 _____________________________________ Time: 12:43:47 PM PST US From: Mark Kettering Subject: Re: KIS-List: KIS TR-1 Airfoil >From my calculations when I worked for Tri-R, the elevator push pull tube was undersized for it's length. Then talking with Vance it came up that the up throw was well less than calculated due to contact between the push tube and horizontal. The solution talked about was to put an additional idler well aft in the fuselage and as low as possible and then the most aft tube would no longer contact the horizontal. This would solve two issues at the same time. I also like the idea of increasing the length of the control arm on the elevator and changing the ratio on the current idler. This would reduce the load on the push tube and increase the clearance from the tube to the horizontal. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:34 PM Subject: Re: KIS-List: KIS TR-1 Airfoil As far as I can tell it is stock as per the plans. Maybe that is why the VG's made a significant difference. Galin On Sun, Jan 13, 2013 at 2:12 PM, Mark Kettering wrote: Hello Galin, Is your elevator linkage stock as per the plans or modified to allow for more up elevator? I think this modification is very important and may prevent the need for VG's. The stock method had the control tube hit the bottom of the horizontal inside the tail before a reasonable up elevator deflection limit could be reached. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:20 AM Subject: Re: KIS-List: KIS TR-1 Airfoil Jan; What do you mean when you say "Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line." Can you provide a photo of what you mean? This sounds like a viable option for those of us that have flying airplanes and can't re-work the wing/tail. I used the VG's from Stolspeed.com on the elevator and they made a significant improvement while landing my TR-4. GalinN819PR On Fri, Jan 11, 2013 at 4:36 PM, Propellerjan wrote: KIS TR-1 Airfoil In the search for information to calculate an optimum propeller for the KIS I0-240 I found a lot of information and thoughts about its handling especially during landing. When picking an airfoil for a airplane project that is about the last thing to do before the design is set in stone. The wing area is determined in respect of stall speed with flap arrangement. When having MTOW, wing aspect ratio and wing area, we can calculate speed and lift coefficient, CL The speed we use for this will be where we spend most of the time, not stall speed and not top speed, but climb and normal cruise speed. So in this range the airfoil should have the lowest drag, if it was an airliner that spend most of its time climbing and cruising at high altitude at low indicated speed it will be at similar CL most of the time (but Mach Nr will play its roll) All aircrafts that see any production see an increase in installed power and weight. If this was in the design of the KIS from start I dont know, but the prototype had a Limbach from start if understand it correctly, and several hundred lbs less weight. Most seem to have the I0-240B engine installed now and a MTOW of 1450 lb or so. And it is cruising at around 140 kts. This give an lift coefficient, of around CL 0.3 at cruise, it mean that an airfoil with higher camber would have been better then the current N-63A215, where the 3:d last digit tell the designed CL So it have an airfoil designed for higher speeds, but no meaning to have that, no one cruise at WOT at SL, but most cruise at 65-75% power from 2000 to 8000 or 12000 The NACA 6x- series isnt the best with today standard, rumour says that the NACA screwed up when publishing these new airfoils with a faulty design that they could not take back. An Harry Riblett GA-37A315 would be a better choice, it have gentler stall, and will show less drag at both cruise and climb, The difference between Riblett and NACA is that the nose radii is placed correctly on the Riblett. The Riblett will have about 7-8% higher CLmax. I draw up both airfoils for evaluation and when aligning the portion where main and after spar will be, it is a different of 1 degree at the chord line. (From nose radii to trailing edge) The NACA is in Green >From the main spar and back there is very little difference in shape, meaning the lift at same angle will be about the same with this difference in angle The chord line is just a reference line that is convenient to draw and measure, but aerodynamically it is almost a fictive line, the important line or angle of an airfoil is the zero lift angle, from this line the lift is generated if it is given an angle to the relative wind, think of an symmetric airfoil where the zero lift line and chord line is the same, and at alpha zero it will not produce any lift. An airfoil with camber will produce lift even if the chord line is at alpha zero, or slightly negative, because the zero lift line will have a positive alpha to the wind. To make a cambered airfoil to produce zero lift, the nose have to be lowered until the zero lift line is parallel to the wind, so an cambered airfoil is said to have a zero lift angle of minus some degree depending of the camber, it can be -1 to -6 degree on common airfoils and camber. The NACA 63A-215 have a zero lift angle of -1.64 degree, and the Riblett GA-37A315 -2.14 degree. A difference of 0.50 degree. The lift slope Cl alpha is depending on the wing aspect ratio, for a AR of 6, the slope of the lift curve is CL = 2Phi / 1+2/A2 = 2Phi / 1 + 2 / 6 = 4.71239 per radian Or 4.71239 / 57.3 = 0.08224 per degree The original wing is 3 degree up from chord line to fuselage reference line, so if we fly it with the reference line horizontal the wing CL is 3 - -1.64 = 4.64 degree a 0,08224 = 0,38 CL. The GA-37A315 will be 1 degree less measured at the chord line, so 2 - -2.14 = 4.14. so CL with fuselage level will be 0.34 It means that at higher speeds the nose down angle will be 0.5 degree less. Lets say we cruse at 165 MPH TAS @ 8000 and 1450 Lb the CL will be 0.30 plus the fact that the wing have to carry the down force from tail plane. Both airfoils have a negative pitch moment of 0.05, the Riblett just a little more then the NACA due to more camber. The load at the tail is its moment times the wing chord and area, times dynamic pressure. Divided with tail length. It will be about 84-85 lb down force at cruise if CG is at 25% chord So the wing then will carry 1535 lb or CL 0.32 A CG further back will reduce negative lift and then reduce induced drag. (And reversed.) 1450 lb at after limit will reduce down force at the tail with 10 lb at forward limit it will ad 35 lb to a total lift the wing have to do of 1570 lb or CL 0.33 A CG to forward and the elevator will not be able to hold the nose up with flaps, to far back and it will be sensitive on the stick. Then we come into: Nose drop at landing, sounds like ground effect, when closer to ground the down wash from wing is flattened out, meaning the tail will have less down force. With a horizontal stab area of just a bit over 17% of the wing area, seems small, even if the tail arm is long. One reason for the elevator not be up to the job can also be the tail incidence, 0.5 - 0.75 degree down might help. (but hard to fix that now) Seems like, longer elevators chords is a good thing, 1,75 longer chord move the hinge line to 60% chord/40% elevator. (about normal) And VG's, seems to help, it means something is wrong from start, to small elevator or wrong incidence. Or to small H.- tail area or all three. The Wing Fuselage fairing should be expanding and 10% of the chord at the trailing edge, according to Raymer, It mean in my eyes it should be 10% of the local chord, so mid chord it is 5% of the total chord length. I dont see anyone on Matronics talks about if they sealed the control surface hinge gaps with tape. That will make a big difference. Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line. Having them unsealed is like driving with the parking brake on. On a Kitfox it is the difference of being able to make a 3-point or not with or without sealing the elevator gap. Jan Carlsson JC Propeller Design Ps. Sorry to say, I have never been onboard a KIS. -------- www.jcpropellerdesign.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=392088#392088 Attachments: http://forums.matronics.com//files/63a215_37a315_le_rad_133.jpg http://forums.matronics.com//files/63a215_37a315_184.jpg ========== rget="_blank">http://www.matronics.com/Navigator?KIS-List ========== http://forums.matronics.com ========== le, List Admin. ="_blank">http://www.matronics.com/contribution ========== ========== rget="_blank">http://www.matronics.com/Navigator?KIS-List ========== http://forums.matronics.com ========== le, List Admin. ="_blank">http://www.matronics.com/contribution ========== ________________________________ Message 3 _____________________________________ Time: 01:37:59 PM PST US From: Scott Stearns Subject: Re: KIS-List: KIS TR-1 Airfoil Another=C2-option would be to make a reducer fitting and transition to a smaller tube for the portion that goes under the horizontal.=C2- An ideal push tube is tapered and you only need the full diameter at the center.=C2 - The fantasy push tube is tapered unidirectional boron fiber.=0A=C2- =0ACan someone post the tube length and=C2-diameter/wall thickness=C2-a nd the distance from the LE of the horizontal tail=C2-to the point where the tube bolts to the elevator?=0A=C2-=0AAnother option is to switch the whole tube=C2-to a smaller diameter steel tube.=C2- It=C2-would be th e easiest solution,=C2-but it would add some wieght.=C2- 3-4 pounds pro bably.=C2- =0A=C2-=0AMy forward pitch control tube is 3/4" diameter=C2 -steel on my much modified=C2-TR-1 to minimize the width of the center console.=C2-=0A=C2-=0AScott=0A =0A=0A________________________________ =0A From: Mark Kettering =0ATo: kis-list@matronics.c om =0ASent: Monday, January 14, 2013 12:43 PM=0ASubject: Re: KIS-List: KIS @earthlink.net>=0A=0A>From my calculations when I worked for Tri-R, the ele vator push pull tube was undersized for it's length.=C2- Then talking wit h Vance it came up that the up throw was well less than calculated due to c ontact between the push tube and horizontal.=C2- The solution talked abou t was to put an additional idler well aft in the fuselage and as low as pos sible and then the most aft tube would no longer contact the horizontal.=C2 - This would solve two issues at the same time.=0A=0AI also like the idea of increasing the length of the control arm on the elevator and changing t he ratio on the current idler.=C2- This would reduce the load on the push tube and increase the clearance from the tube to the horizontal.=0A=0AMark =0A=0A-----Original Message-----=0A=0AFrom: Galin Hernandez =0A=0ASent: Jan 13, 2013 10:34 PM=0A=0ATo: kis-list@matronics.com=0A=0ASubject: Re: KIS-Li st: KIS TR-1 Airfoil=0A=0A=0A=0AAs far as I can tell it is stock as per the plans. Maybe that is why the VG's made a significant difference. Galin=0A =0AOn Sun, Jan 13, 2013 at 2:12 PM, Mark Kettering hlink.net>=0A=0A=0A=0A=0A=0AHello Galin,=0A=0A=0A=0AIs your elevator linkag e stock as per the plans or modified to allow for more up elevator?=C2- I think this modification is very important and may prevent the need for VG' s.=C2- The stock method had the control tube hit the bottom of the horizo ntal inside the tail before a reasonable up elevator deflection limit could be reached.=0A=0A=0A=0A=0A=0AMark=0A=0A=0A=0A=0A=0A-----Original Message-- ---=0A=0A=0A=0AFrom: Galin Hernandez=0A=0A=0A=0ASent: Jan 13, 2013 10:20 AM =0A=0A=0A=0ATo: kis-list@matronics.com=0A=0A=0A=0ASubject: Re: KIS-List: KI S TR-1 Airfoil=0A=0A=0A=0A=0A=0A=0A=0AJan; What do you mean when you say "T ape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the fla p hinge line." Can you provide a photo of what you mean? This sounds like a viable option for those of us that have flying airplanes and can't re-work the wing/tail.=0A=0A=0A=0A=0A=0A=0A=0AI used the VG's from Stolspeed.com o n the elevator and they made a significant improvement while landing my TR- 4.=0A=0AGalinN819PR=0A=0A=0A=0AOn Fri, Jan 11, 2013 at 4:36 PM, Propellerja n wrote:=0A=0A=0A=0A=0A=0A--> KIS-List message p osted by: "Propellerjan" =0A=0A=0A=0A=0A=0A=0A=0A =0A=0A=0A=0AKIS TR-1 Airfoil=0A=0A=0A=0A=0A=0A=0A=0AIn the search for infor mation to calculate an optimum propeller for the KIS I0-240 I found a lot o f information and thoughts about its handling especially during landing.=0A =0A=0A=0A=0A=0A=0A=0AWhen picking an airfoil for a airplane project that is about the last thing to do before the design is set in stone. The wing are a is determined in respect of stall speed with flap arrangement.=0A=0A=0A =0AWhen having MTOW, wing aspect ratio and wing area, we can calculate spee d and lift coefficient, CL=0A=0A=0A=0A=0A=0A=0A=0AThe speed we use for this will be where we spend most of the time, not stall speed and not top speed , but climb and normal cruise speed. So in this range the airfoil should ha ve the lowest drag, if it was an airliner that spend most of its time climb ing and cruising at high altitude at low indicated speed it will be at simi lar CL most of the time (but Mach Nr will play its roll)=0A=0A=0A=0A=0A=0A =0A=0A=0A=0A=0A=0A=0A=0AAll aircrafts that see any production see an increa se in installed power and weight. If this was in the design of the KIS from start I don=99t know, but the prototype had a Limbach from start if understand it correctly, and several hundred lbs less weight.=0A=0A=0A=0A =0A=0A=0A=0A=0A=0A=0A=0A=0A=0AMost seem to have the I0-240B engine installe d now and a MTOW of 1450 lb or so. And it is cruising at around 140 kts. Th is give an lift coefficient, of around CL 0.3 at cruise, it mean that an ai rfoil with higher camber would have been better then the current N-63A215, where the 3:d last digit tell the designed CL So it have an airfoil designe d for higher speeds, but no meaning to have that, no one cruise at WOT at S L, but most cruise at 65-75% power from 2000=C2=B4 to 8000 or 12000=C2=B4 =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe NACA 6x- series isn=99t the best with today standard, rumour says that the NACA screwed up when pu blishing these new airfoils with a faulty design that they could not take b ack.=0A=0A=0A=0A=0A=0A=0A=0AAn Harry Riblett GA-37A315 would be a better ch oice, it have gentler stall, and will show less drag at both cruise and cli mb, The difference between Riblett and NACA is that the nose radii is place d correctly on the Riblett. The Riblett will have about 7-8% higher CLmax. =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AI draw up both airfoils for evalu ation and when aligning the portion where main and after spar will be, it i s a different of 1 degree at the chord line. (From nose radii to trailing e dge)=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe NACA is in Green=0A=0A=0A=0A=0A =0A=0A=0A=0A=0A=0A=0A>From the main spar and back there is very little diff erence in shape, meaning the lift at same angle will be about the same with this difference in angle=0A=0A=0A=0A=0A=0A=0A=0AThe chord line is just a r eference line that is convenient to draw and measure, but aerodynamically i t is almost a fictive line, the important line or angle of an airfoil is th e zero lift angle, from this line the lift is generated if it is given an a ngle to the relative wind, think of an symmetric airfoil where the zero lif t line and chord line is the same, and at alpha zero it will not produce an y lift.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AAn airfoil with camber wil l produce lift even if the chord line is at alpha zero, or slightly negativ e, because the zero lift line will have a positive alpha to the wind.=0A=0A =0A=0ATo make a cambered airfoil to produce zero lift, the nose have to be lowered until the zero lift line is parallel to the wind, so an cambered ai rfoil is said to have a zero lift angle of minus some degree depending of t he camber, it can be -1 to -6 degree on common airfoils and camber.=0A=0A =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe NACA 63A-215 have a zer o lift angle of -1.64 degree, and the Riblett GA-37A315 -2.14 degree.=0A=0A =0A=0AA difference of 0.50 degree.=0A=0A=0A=0A=0A=0A=0A=0AThe lift slope Cl alpha=C2=B4 is depending on the wing aspect ratio, for a AR of 6, the slop e of the lift curve is CL=C2=B5 = 2Phi / 1+2/A2 = 2Phi / 1 + 2 / 6 = 4.71239 per radian=0A=0A=0A=0AOr 4.71239 / 57.3 = 0.08224 per degree=0A =0A=0A=0A=0A=0A=0A=0AThe original wing is 3 degree up from chord line to fu selage reference line, so if we fly it with the reference line horizontal t he wing CL=C2- =C2- is 3 - -1.64 = 4.64 degree a 0,08224 = 0,38 CL. =0A=0A=0A=0A=0A=0A=0A=0AThe GA-37A315 will be 1 degree less measured at the chord line, so 2 - -2.14 = 4.14. so CL with fuselage level will be 0.34 =0A=0A=0A=0AIt means that at higher speeds the nose down angle will be 0.5 degree less.=0A=0A=0A=0A=0A=0A=0A=0ALets say we cruse at 165 MPH TAS @ 8000 =C2=B4 and 1450 Lb the CL will be 0.30 plus the fact that the wing have to carry the down force from tail plane. Both airfoils have a negative pitch m oment of 0.05, the Riblett just a little more then the NACA due to more cam ber.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe load at the tail is its moment times the wing chord and area, times dynamic pressure.=0A=0A=0A=0ADivided with ta il length.=0A=0A=0A=0AIt will be about 84-85 lb down force at cruise if CG is at 25% chord=0A=0A=0A=0ASo the wing then will carry 1535 lb or CL=C2- 0.32=0A=0A=0A=0A=0A=0A=0A=0AA CG further back will reduce negative lift and then reduce induced drag. (And reversed.)=0A=0A=0A=0A1450 lb at after limi t will reduce down force at the tail with 10 lb=0A=0A=0A=0Aat forward limit it will ad 35 lb to a total lift the wing have to do of 1570 lb or CL 0.33 =0A=0A=0A=0A=0A=0A=0A=0AA CG to forward and the elevator will not be able t o hold the nose up with flaps, to far back and it will be sensitive on the stick. Then we come into:=0A=0A=0A=0A=0A=0A=0A=0ANose drop at landing, soun ds like ground effect, when closer to ground the down wash from wing is fla ttened out, meaning the tail will have less down force.=0A=0A=0A=0AWith a h orizontal stab area of just a bit over 17% of the wing area, seems small, e ven if the tail arm is long.=0A=0A=0A=0AOne reason for the elevator not be up to the job can also be the tail incidence, 0.5 - 0.75 degree down might help.=C2- (but hard to fix that now)=0A=0A=0A=0ASeems like, longer elevat ors chords is a good thing, 1,75=9D longer chord move the hinge line to 60% chord/40% elevator.=C2- (about =9Cnormal=9D)=0A=0A=0A =0AAnd VG's, seems to help, it means something is wrong from start, to smal l elevator or wrong incidence. Or to small H.- tail area or all three.=0A =0A=0A=0A=0A=0A=0A=0AThe Wing =93 Fuselage fairing should be expandin g and 10% of the chord at the trailing edge, according to Raymer, It mean i n my eyes it should be 10% of the local chord, so mid chord it is 5% of the total chord length.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AI don =99t see anyone on Matronics talks about if they sealed the control surface hinge gaps with tape. That will make a big difference. Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, ins ide the rudder, inside the aileron, and bottom of the flap hinge line.=0A =0A=0A=0A=0A=0A=0A=0A=0A=0AHaving them unsealed=C2- is like driving with the parking brake on.=0A=0A=0A=0AOn a Kitfox it is the difference of being able to make a 3-point or not with or without sealing the elevator gap.=0A =0A=0A=0A=0A=0A=0A=0AJan Carlsson=0A=0A=0A=0AJC Propeller Design=0A=0A=0A =0A=0A=0A=0A=0APs. Sorry to say, I have never been onboard a KIS.=0A=0A=0A =0A=0A=0A=0A=0A--------=0A=0A=0A=0Awww.jcpropellerdesign.com=0A=0A=0A=0A=0A =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0ARead this topic online here: =0A=0A=0A=0A=0A=0A=0A=0Ahttp://forums.matronics.com/viewtopic.php?p=39208 8#392088=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AAttachm ents:=0A=0A=0A=0A=0A=0A=0A=0Ahttp://forums.matronics.com//files/63a215_37a3 15_le_rad_133.jpg=0A=0A=0A=0Ahttp://forums.matronics.com//files/63a215_37a3 15_184.jpg=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A= ===========0A=0A=0A=0Arget="_blank">http://www.matron ics.com/Navigator?KIS-List=0A=0A=0A=0A============0A =0A=0A=0Ahttp://forums.matronics.com/=0A=0A=0A=0A======== ====0A=0A=0A=0Ale, List Admin.=0A=0A=0A=0A="_blank">http://www.matr onics.com/contribution=0A=0A=0A=0A============0A=0A =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A =0A=0A=0A============0A=0Arget="_blank">http://www. matronics.com/Navigator?KIS-List=0A=0A============0A =0Ahttp://forums.matronics.com/=0A=0A============0A =0Ale, List Admin.=0A=0A="_blank">http://www.matronics.com/contribution =0A=0A============0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A == ________________________________ Message 4 _____________________________________ Time: 05:49:23 PM PST US From: Mark Kettering Subject: Re: KIS-List: KIS TR-1 Airfoil The current aft elevator tube is 6061 T6, 120" long, 1.25" dia, 0.065" wall with a margin of safety of -0.39. FYI, the forward steel tube is 4130, 51.25" long, 0.74" dia, 0.035" wall with a margin of safety of -0.35. The margin of safety must be positive to be safe. Steel or aluminum is a wash for weight to stiffness ratio. But for the long elevator tube to be 1" dia steel it would need to be 0.075 wall or thicker. This would make it over 6 times more heavy than the aluminum tube (about 10 lbs more) and only give you 0.125" more clearance on the horizontal. Diameter really helps for tube compression buckling resistance. Using two tubes really reduces the load. If 2 tubes were used and they were each 60" long they could be 6061 T6, 1" dia, 0.058" wall and still have a 0.11 margin of safety. As Scott said, double tapered would really help. I think the most simple solution is to increase the length of the rudder control horn (from 4' to 5") and slightly change the idler ratio (change the long side to 5"). Not only does this increase the clearance but it also reduces the load on the push tube. Still not a positive margin but only about half as negative. Mark -----Original Message----- From: Scott Stearns Sent: Jan 14, 2013 4:37 PM Subject: Re: KIS-List: KIS TR-1 Airfoil Another option would be to make a reducer fitting and transition to a smaller tube for the portion that goes under the horizontal. An ideal push tube is tapered and you only need the full diameter at the center. The fantasy push tube is tapered unidirectional boron fiber. Can someone post the tube length and diameter/wall thickness and the distance from the LE of the horizontal tail to the point where the tube bolts to the elevator? Another option is to switch the whole tube to a smaller diameter steel tube. It would be the easiest solution, but it would add some wieght. 3-4 pounds probably. My forward pitch control tube is 3/4" diameter steel on my much modified TR-1 to minimize the width of the center console. Scott From: Mark Kettering To: kis-list@matronics.com Sent: Monday, January 14, 2013 12:43 PM Subject: Re: KIS-List: KIS TR-1 Airfoil >From my calculations when I worked for Tri-R, the elevator push pull tube was undersized for it's length. Then talking with Vance it came up that the up throw was well less than calculated due to contact between the push tube and horizontal. The solution talked about was to put an additional idler well aft in the fuselage and as low as possible and then the most aft tube would no longer contact the horizontal. This would solve two issues at the same time. I also like the idea of increasing the length of the control arm on the elevator and changing the ratio on the current idler. This would reduce the load on the push tube and increase the clearance from the tube to the horizontal. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:34 PM Subject: Re: KIS-List: KIS TR-1 Airfoil As far as I can tell it is stock as per the plans. Maybe that is why the VG's made a significant difference. Galin On Sun, Jan 13, 2013 at 2:12 PM, Mark Kettering wrote: Hello Galin, Is your elevator linkage stock as per the plans or modified to allow for more up elevator? I think this modification is very important and may prevent the need for VG's. The stock method had the control tube hit the bottom of the horizontal inside the tail before a reasonable up elevator deflection limit could be reached. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:20 AM Subject: Re: KIS-List: KIS TR-1 Airfoil Jan; What do you mean when you say "Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line." Can you provide a photo of what you mean? This sounds like a viable option for those of us that have flying airplanes and can't re-work the wing/tail. I used the VG's from Stolspeed.com on the elevator and they made a significant improvement while landing my TR-4. GalinN819PR On Fri, Jan 11, 2013 at 4:36 PM, Propellerjan wrote: KIS TR-1 Airfoil In the search for information to calculate an optimum propeller for the KIS I0-240 I found a lot of information and thoughts about its handling especially during landing. When picking an airfoil for a airplane project that is about the last thing to do before the design is set in stone. The wing area is determined in respect of stall speed with flap arrangement. When having MTOW, wing aspect ratio and wing area, we can calculate speed and lift coefficient, CL The speed we use for this will be where we spend most of the time, not stall speed and not top speed, but climb and normal cruise speed. So in this range the airfoil should have the lowest drag, if it was an airliner that spend most of its time climbing and cruising at high altitude at low indicated speed it will be at similar CL most of the time (but Mach Nr will play its roll) All aircrafts that see any production see an increase in installed power and weight. If this was in the design of the KIS from start I dont know, but the prototype had a Limbach from start if understand it correctly, and several hundred lbs less weight. Most seem to have the I0-240B engine installed now and a MTOW of 1450 lb or so. And it is cruising at around 140 kts. This give an lift coefficient, of around CL 0.3 at cruise, it mean that an airfoil with higher camber would have been better then the current N-63A215, where the 3:d last digit tell the designed CL So it have an airfoil designed for higher speeds, but no meaning to have that, no one cruise at WOT at SL, but most cruise at 65-75% power from 2000 to 8000 or 12000 The NACA 6x- series isnt the best with today standard, rumour says that the NACA screwed up when publishing these new airfoils with a faulty design that they could not take back. An Harry Riblett GA-37A315 would be a better choice, it have gentler stall, and will show less drag at both cruise and climb, The difference between Riblett and NACA is that the nose radii is placed correctly on the Riblett. The Riblett will have about 7-8% higher CLmax. I draw up both airfoils for evaluation and when aligning the portion where main and after spar will be, it is a different of 1 degree at the chord line. (From nose radii to trailing edge) The NACA is in Green >From the main spar and back there is very little difference in shape, meaning the lift at same angle will be about the same with this difference in angle The chord line is just a reference line that is convenient to draw and measure, but aerodynamically it is almost a fictive line, the important line or angle of an airfoil is the zero lift angle, from this line the lift is generated if it is given an angle to the relative wind, think of an symmetric airfoil where the zero lift line and chord line is the same, and at alpha zero it will not produce any lift. An airfoil with camber will produce lift even if the chord line is at alpha zero, or slightly negative, because the zero lift line will have a positive alpha to the wind. To make a cambered airfoil to produce zero lift, the nose have to be lowered until the zero lift line is parallel to the wind, so an cambered airfoil is said to have a zero lift angle of minus some degree depending of the camber, it can be -1 to -6 degree on common airfoils and camber. The NACA 63A-215 have a zero lift angle of -1.64 degree, and the Riblett GA-37A315 -2.14 degree. A difference of 0.50 degree. The lift slope Cl alpha is depending on the wing aspect ratio, for a AR of 6, the slope of the lift curve is CL = 2Phi / 1+2/A2 = 2Phi / 1 + 2 / 6 = 4.71239 per radian Or 4.71239 / 57.3 = 0.08224 per degree The original wing is 3 degree up from chord line to fuselage reference line, so if we fly it with the reference line horizontal the wing CL is 3 - -1.64 = 4.64 degree a 0,08224 = 0,38 CL. The GA-37A315 will be 1 degree less measured at the chord line, so 2 - -2.14 = 4.14. so CL with fuselage level will be 0.34 It means that at higher speeds the nose down angle will be 0.5 degree less. Lets say we cruse at 165 MPH TAS @ 8000 and 1450 Lb the CL will be 0.30 plus the fact that the wing have to carry the down force from tail plane. Both airfoils have a negative pitch moment of 0.05, the Riblett just a little more then the NACA due to more camber. The load at the tail is its moment times the wing chord and area, times dynamic pressure. Divided with tail length. It will be about 84-85 lb down force at cruise if CG is at 25% chord So the wing then will carry 1535 lb or CL 0.32 A CG further back will reduce negative lift and then reduce induced drag. (And reversed.) 1450 lb at after limit will reduce down force at the tail with 10 lb at forward limit it will ad 35 lb to a total lift the wing have to do of 1570 lb or CL 0.33 A CG to forward and the elevator will not be able to hold the nose up with flaps, to far back and it will be sensitive on the stick. Then we come into: Nose drop at landing, sounds like ground effect, when closer to ground the down wash from wing is flattened out, meaning the tail will have less down force. With a horizontal stab area of just a bit over 17% of the wing area, seems small, even if the tail arm is long. One reason for the elevator not be up to the job can also be the tail incidence, 0.5 - 0.75 degree down might help. (but hard to fix that now) Seems like, longer elevators chords is a good thing, 1,75 longer chord move the hinge line to 60% chord/40% elevator. (about normal) And VG's, seems to help, it means something is wrong from start, to small elevator or wrong incidence. Or to small H.- tail area or all three. The Wing Fuselage fairing should be expanding and 10% of the chord at the trailing edge, according to Raymer, It mean in my eyes it should be 10% of the local chord, so mid chord it is 5% of the total chord length. I dont see anyone on Matronics talks about if they sealed the control surface hinge gaps with tape. That will make a big difference. Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line. Having them unsealed is like driving with the parking brake on. On a Kitfox it is the difference of being able to make a 3-point or not with or without sealing the elevator gap. Jan Carlsson JC Propeller Design Ps. Sorry to say, I have never been onboard a KIS. -------- www.jcpropellerdesign.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=392088#392088 Attachments: http://forums.matronics.com//files/63a215_37a315_le_rad_133.jpg http://forums.matronics.com//files/63a215_37a315_184.jpg ========== rget="_blank">http://www.matronics.com/Navigator?KIS-List ========== http://forums.matronics.com/ ========== le, List Admin. ="_blank">http://www.matronics.com/contribution ========== ========== rget="_blank">http://www.matronics.com/Navigator?KIS-List ========== http://forums.matronics.com/ ========== le, List Admin. ="_blank">http://www.matronics.com/contribution ==========
="" http://www.===================== ________________________________ Message 5 _____________________________________ Time: 06:09:05 PM PST US From: Flyinisfun@aol.com Subject: Re: KIS-List: KIS TR-1 Airfoil This is Jesse, I built and used the materials that came with the kit. I achieved the degrees of up elevator called for in the prints. How close the down arm f rom the elevator comes to hitting something I don't know now. "I'm surprised these problems didn't surface before now. Maybe they did and I missed the m, which is it? I'm assuming we're still talking about the TR-1. In a message dated 1/14/2013 6:49:26 P.M. Mountain Standard Time, mantafs@earthlink.net writes: --> KIS-List message posted by: Mark Kettering The current aft elevator tube is 6061 T6, 120" long, 1.25" dia, 0.065" wall with a margin of safety of -0.39. FYI, the forward steel tube is 413 0, 51.25" long, 0.74" dia, 0.035" wall with a margin of safety of -0.35. The margin of safety must be positive to be safe. Steel or aluminum is a wash for weight to stiffness ratio. But for the long elevator tube to be 1" dia steel it would need to be 0.075 wall or thicker. This would make it over 6 times more heavy than the aluminum tub e (about 10 lbs more) and only give you 0.125" more clearance on the horizon tal. Diameter really helps for tube compression buckling resistance. Using two tubes really reduces the load. If 2 tubes were used and they were each 60" long they could be 6061 T6, 1" dia, 0.058" wall and still ha ve a 0.11 margin of safety. As Scott said, double tapered would really help. I think the most simple solution is to increase the length of the rudder control horn (from 4' to 5") and slightly change the idler ratio (change t he long side to 5"). Not only does this increase the clearance but it also reduces the load on the push tube. Still not a positive margin but only about half as negative. Mark -----Original Message----- From: Scott Stearns Sent: Jan 14, 2013 4:37 PM Subject: Re: KIS-List: KIS TR-1 Airfoil Another option would be to make a reducer fitting and transition to a smaller tube for the portion that goes under the horizontal. An ideal pus h tube is tapered and you only need the full diameter at the center. The fantasy push tube is tapered unidirectional boron fiber. Can someone post the tube length and diameter/wall thickness and the distance from the LE of th e horizontal tail to the point where the tube bolts to the elevator? Another option is to switch the whole tube to a smaller diameter steel tube. It would be the easiest solution, but it would add some wieght. 3-4 pounds probably. My forward pitch control tube is 3/4" diameter steel on my much modified TR-1 to minimize the width of the center console. Scott From: Mark Kettering Sent: Monday, January 14, 2013 12:43 PM Subject: Re: KIS-List: KIS TR-1 Airfoil --> KIS-List message posted by: Mark Kettering >From my calculations when I worked for Tri-R, the elevator push pull tube was undersized for it's length. Then talking with Vance it came up that the up throw was well less than calculated due to contact between the push tube and horizontal. The solution talked about was to put an additional idler well aft in the fuselage and as low as possible and then the most af t tube would no longer contact the horizontal. This would solve two issues at the same time. I also like the idea of increasing the length of the control arm on the elevator and changing the ratio on the current idler. This would reduce t he load on the push tube and increase the clearance from the tube to the horizontal. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:34 PM Subject: Re: KIS-List: KIS TR-1 Airfoil As far as I can tell it is stock as per the plans. Maybe that is why the VG's made a significant difference. Galin On Sun, Jan 13, 2013 at 2:12 PM, Mark Kettering wrote: Hello Galin, Is your elevator linkage stock as per the plans or modified to allow for more up elevator? I think this modification is very important and may prevent the need for VG's. The stock method had the control tube hit the bottom of the horizontal inside the tail before a reasonable up elevator deflection limit could be reached. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:20 AM Subject: Re: KIS-List: KIS TR-1 Airfoil Jan; What do you mean when you say "Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line." Can you provide a photo of what you mean? This sounds like a viable option for those of us t hat have flying airplanes and can't re-work the wing/tail. I used the VG's from Stolspeed.com on the elevator and they made a significant improvement while landing my TR-4. GalinN819PR On Fri, Jan 11, 2013 at 4:36 PM, Propellerjan wrote: KIS TR-1 Airfoil In the search for information to calculate an optimum propeller for the KIS I0-240 I found a lot of information and thoughts about its handling especially during landing. When picking an airfoil for a airplane project that is about the last thing to do before the design is set in stone. The wing area is determined in respect of stall speed with flap arrangement. When having MTOW, wing aspect ratio and wing area, we can calculate speed and lift coefficient, CL The speed we use for this will be where we spend most of the time, not stall speed and not top speed, but climb and normal cruise speed. So in th is range the airfoil should have the lowest drag, if it was an airliner that spend most of its time climbing and cruising at high altitude at low indicated speed it will be at similar CL most of the time (but Mach Nr wil l play its roll) All aircrafts that see any production see an increase in installed power and weight. If this was in the design of the KIS from start I don=99 t know, but the prototype had a Limbach from start if understand it correctly, and several hundred lbs less weight. Most seem to have the I0-240B engine installed now and a MTOW of 1450 lb or so. And it is cruising at around 140 kts. This give an lift coefficient, of around CL 0.3 at cruise, it mean that an airfoil with higher camber would have been better then the current N-63A215, where the 3:d last digit tell the designe d CL So it have an airfoil designed for higher speeds, but no meaning to have that, no one cruise at WOT at SL, but most cruise at 65-75% power from 2000 =C2=B4 to 8000 or 12000=C2=B4 The NACA 6x- series isn=99t the best with today standard, rumour say s that the NACA screwed up when publishing these new airfoils with a faulty desig n that they could not take back. An Harry Riblett GA-37A315 would be a better choice, it have gentler stall, and will show less drag at both cruise and climb, The difference be tween Riblett and NACA is that the nose radii is placed correctly on the Riblett . The Riblett will have about 7-8% higher CLmax. I draw up both airfoils for evaluation and when aligning the portion where main and after spar will be, it is a different of 1 degree at the chord line. (From nose radii to trailing edge) The NACA is in Green >From the main spar and back there is very little difference in shape, meaning the lift at same angle will be about the same with this difference in angle The chord line is just a reference line that is convenient to draw and measure, but aerodynamically it is almost a fictive line, the important li ne or angle of an airfoil is the zero lift angle, from this line the lift is generated if it is given an angle to the relative wind, think of an symmet ric airfoil where the zero lift line and chord line is the same, and at alpha zero it will not produce any lift. An airfoil with camber will produce lift even if the chord line is at alpha zero, or slightly negative, because the zero lift line will have a positive alpha to the wind. To make a cambered airfoil to produce zero lift, the nose have to be lowered until the zero lift line is parallel to the wind, so an cambered a irfoil is said to have a zero lift angle of minus some degree depending of the camber, it can be -1 to -6 degree on common airfoils and camber. The NACA 63A-215 have a zero lift angle of -1.64 degree, and the Riblett GA-37A315 -2.14 degree. A difference of 0.50 degree. The lift slope Cl alpha=C2=B4 is depending on the wing aspect ratio, for a AR of 6, the slope of the lift curve is CL=C2=B5 = 2Phi / 1+2/A2 = 2Phi / 1 + 2 / 6 = 4.71239 per radian Or 4.71239 / 57.3 = 0.08224 per degree The original wing is 3 degree up from chord line to fuselage reference line, so if we fly it with the reference line horizontal the wing CL is 3 - -1.64 = 4.64 degree a 0,08224 = 0,38 CL. The GA-37A315 will be 1 degree less measured at the chord line, so 2 - -2.14 = 4.14. so CL with fuselage level will be 0.34 It means that at higher speeds the nose down angle will be 0.5 degree less .. Lets say we cruse at 165 MPH TAS @ 8000=C2=B4 and 1450 Lb the CL will be 0 .30 plus the fact that the wing have to carry the down force from tail plane. Both airfoils have a negative pitch moment of 0.05, the Riblett just a lit tle more then the NACA due to more camber. The load at the tail is its moment times the wing chord and area, times dynamic pressure. Divided with tail length. It will be about 84-85 lb down force at cruise if CG is at 25% chord So the wing then will carry 1535 lb or CL 0.32 A CG further back will reduce negative lift and then reduce induced drag. (And reversed.) 1450 lb at after limit will reduce down force at the tail with 10 lb at forward limit it will ad 35 lb to a total lift the wing have to do of 1570 lb or CL 0.33 A CG to forward and the elevator will not be able to hold the nose up with flaps, to far back and it will be sensitive on the stick. Then we come into: Nose drop at landing, sounds like ground effect, when closer to ground the down wash from wing is flattened out, meaning the tail will have less down force. With a horizontal stab area of just a bit over 17% of the wing area, seems small, even if the tail arm is long. One reason for the elevator not be up to the job can also be the tail incidence, 0.5 - 0.75 degree down might help. (but hard to fix that now) Seems like, longer elevators chords is a good thing, 1,75=9D longer chord move the hinge line to 60% chord/40% elevator. (about =9Cnormal =9D) And VG's, seems to help, it means something is wrong from start, to small elevator or wrong incidence. Or to small H.- tail area or all three. The Wing =93 Fuselage fairing should be expanding and 10% of the cho rd at the trailing edge, according to Raymer, It mean in my eyes it should be 10 % of the local chord, so mid chord it is 5% of the total chord length. I don=99t see anyone on Matronics talks about if they sealed the con trol surface hinge gaps with tape. That will make a big difference. Tape them w ith Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line. Having them unsealed is like driving with the parking brake on. On a Kitfox it is the difference of being able to make a 3-point or not with or without sealing the elevator gap. Jan Carlsson JC Propeller Design Ps. Sorry to say, I have never been onboard a KIS. -------- www.jcpropellerdesign.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=392088#392088 Attachments: http://forums.matronics.com//files/63a215_37a315_le_rad_133.jpg http://forums.matronics.com//files/63a215_37a315_184.jpg rget="_blank">http://www.matronics.com/Navigator?KIS-List http://forums.matronics.com/ le, List Admin. ="_blank">http://www.matronics.com/contribution rget="_blank">http://www.matronics.com/Navigator?KIS-List http://forums.matronics.com/ le, List Admin. ="_blank">http://www.matronics.com/contribution ="" http://www.=================== == ________________________________ Message 6 _____________________________________ Time: 07:10:09 PM PST US From: Scott Stearns Subject: Re: KIS-List: KIS TR-1 Airfoil If a 60" long 1" diameter tube will take the load then just reduce the last 30" of the tube to 1" diameter.=C2- =0A=C2-=0AWe are talking about the Cruiser right?=0A=C2-=0AScott=0A =0A=0A________________________________ =0A From: Mark Kettering =0ATo: kis-list@matronics.c om =0ASent: Monday, January 14, 2013 5:49 PM=0ASubject: Re: KIS-List: KIS T earthlink.net>=0A=0AThe current aft elevator tube is 6061 T6, 120" long, 1. 25" dia, 0.065" wall with a margin of safety of -0.39.=C2- FYI, the forwa rd steel tube is 4130, 51.25" long, 0.74" dia, 0.035" wall with a margin of safety of -0.35.=C2- The margin of safety must be positive to be safe. =0A=0ASteel or aluminum is a wash for weight to stiffness ratio.=C2- But for the long elevator tube to be 1" dia steel it would need to be 0.075 wal l or thicker.=C2- This would make it over 6 times more heavy than the alu minum tube (about 10 lbs more) and only give you 0.125" more clearance on t he horizontal.=C2- Diameter really helps for tube compression buckling re sistance.=0A=0AUsing two tubes really reduces the load.=C2- If 2 tubes we re used and they were each 60" long they could be 6061 T6, 1" dia, 0.058" w all and still have a 0.11 margin of safety.=0A=0AAs Scott said, double tape red would really help.=0A=0AI think the most simple solution is to increase the length of the rudder control horn (from 4' to 5") and slightly change the idler ratio (change the long side to 5").=C2- Not only does this incr ease the clearance but it also reduces the load on the push tube.=C2- Sti ll not a positive margin but only about half as negative.=0A=0AMark=0A=0A-- ---Original Message-----=0A=0AFrom: Scott Stearns =0A=0ASent: Jan 14, 2013 4:37 PM=0A=0ATo: "kis-list@matronics.com" =0A=0ASubject: Re: KIS-List: KIS TR-1 Airfoil=0A=0A=0A=0AAnother option would be to make a reducer fitting a nd transition to a smaller tube for the portion that goes under the horizon tal.=C2- An ideal push tube is tapered and you only need the full diamete r at the center.=C2- The fantasy push tube is tapered unidirectional boro n fiber. Can someone post the tube length and diameter/wall thickness and t he distance from the LE of the horizontal tail to the point where the tube bolts to the elevator? Another option is to switch the whole tube to a smal ler diameter steel tube.=C2- It would be the easiest solution, but it wou ld add some wieght.=C2- 3-4 pounds probably.=C2- My=0Aforward pitch co ntrol tube is 3/4" diameter steel on my much modified TR-1 to minimize the width of the center console.=C2- Scott=0A=C2- =C2- =C2- =C2- From : Mark Kettering =0ATo: kis-list@matronics.com =0ASe nt: Monday, January 14, 2013 12:43 PM=0ASubject: Re: KIS-List:=0AKIS TR-1 A fs@earthlink.net>=0A=0A>From my calculations when I worked for Tri-R, the e levator push pull tube was undersized for it's length.=C2- Then talking w ith Vance it came up that the up throw was well less than calculated due to contact between the push tube and horizontal.=C2- The solution talked ab out was to put an additional idler well aft in the fuselage and as low as p ossible and then the most aft tube would no longer contact the horizontal. =C2- This would solve two issues at the same time.=0A=0AI also like the i dea of increasing the length of the control arm on the elevator and changin g the ratio on the current idler.=C2- This would reduce the load on the p ush tube and increase the clearance from the tube to the horizontal.=0A=0AM ark=0A=0A-----Original Message-----=0A=0AFrom: Galin Hernandez=0A=0A=0ASent : Jan 13, 2013 10:34 PM=0A=0ATo: kis-list@matronics.com=0A=0ASubject: Re: K IS-List: KIS TR-1 Airfoil=0A=0A=0A=0AAs far as I can tell it is stock as pe r the plans. Maybe that is why the VG's made a significant difference. Gali n=0A=0AOn Sun, Jan 13, 2013 at 2:12 PM, Mark Kettering =0A=0A=0A=0A=0A=0AHello Galin,=0A=0A=0A=0AIs your elevator li nkage stock as per the plans or modified to allow for more up elevator?=C2 - I think this modification is very important and may prevent the need fo r VG's.=C2- The stock method had the control tube hit the bottom of=0Athe horizontal inside the tail before a reasonable up elevator deflection limi t could be reached.=0A=0A=0A=0A=0A=0AMark=0A=0A=0A=0A=0A=0A-----Original Me ssage-----=0A=0A=0A=0AFrom: Galin Hernandez=0A=0A=0A=0ASent: Jan 13, 2013 1 0:20 AM=0A=0A=0A=0ATo: kis-list@matronics.com=0A=0A=0A=0ASubject: Re: KIS-L ist: KIS TR-1 Airfoil=0A=0A=0A=0A=0A=0A=0A=0AJan; What do you mean when you say "Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line." Can you provide a photo of what you mean? This sounds like a viable option for those of us that have flying airplanes and can't re-work the wing/tail.=0A=0A=0A=0A=0A=0A=0A=0AI used the VG's from Stolspee d.com on the elevator and they=0Amade a significant improvement while landi ng my TR-4.=0A=0AGalinN819PR=0A=0A=0A=0AOn Fri, Jan 11, 2013 at 4:36 PM, Pr opellerjan wrote:=0A=0A=0A=0A=0A=0A--> KIS-List message posted by: "Propellerjan" =0A=0A=0A=0A=0A =0A=0A=0A=0A=0A=0A=0AKIS TR-1 Airfoil=0A=0A=0A=0A=0A=0A=0A=0AIn the search for information to calculate an optimum propeller for the KIS I0-240 I foun d a lot of information and thoughts about its handling especially during la nding.=0A=0A=0A=0A=0A=0A=0A=0AWhen picking an airfoil for a airplane projec t that is about the last thing to do before the design is set in stone. The wing area is determined in respect of stall speed with flap arrangement. =0A=0A=0A=0AWhen=0Ahaving MTOW, wing aspect ratio and wing area, we can cal culate speed and lift coefficient, CL=0A=0A=0A=0A=0A=0A=0A=0AThe speed we u se for this will be where we spend most of the time, not stall speed and no t top speed, but climb and normal cruise speed. So in this range the airfoi l should have the lowest drag, if it was an airliner that spend most of its time climbing and cruising at high altitude at low indicated speed it will be at similar CL most of the time (but Mach Nr will play its roll)=0A=0A =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AAll aircrafts that see any production s ee an increase in installed power and weight. If this was in the design of the KIS from start I don=99t know, but the prototype had a Limbach fr om start if understand it correctly, and several hundred lbs less weight. =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AMost seem to have the I0-240B eng ine installed now and a MTOW of 1450 lb or so. And it is=0Acruising at arou nd 140 kts. This give an lift coefficient, of around CL 0.3 at cruise, it m ean that an airfoil with higher camber would have been better then the curr ent N-63A215, where the 3:d last digit tell the designed CL So it have an a irfoil designed for higher speeds, but no meaning to have that, no one crui se at WOT at SL, but most cruise at 65-75% power from 2000=C2=B4 to 8000 or 12000=C2=B4=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe NACA 6x- series i sn=99t the best with today standard, rumour says that the NACA screwe d up when publishing these new airfoils with a faulty design that they coul d not take back.=0A=0A=0A=0A=0A=0A=0A=0AAn Harry Riblett GA-37A315 would be a better choice, it have gentler stall, and will show less drag at both cr uise and climb, The difference between Riblett and NACA is that the nose ra dii is placed correctly on the Riblett. The Riblett will have about 7-8% hi gher=0ACLmax.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AI draw up both airfo ils for evaluation and when aligning the portion where main and after spar will be, it is a different of 1 degree at the chord line. (From nose radii to trailing edge)=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe NACA is in Green =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A>From the main spar and back there is v ery little difference in shape, meaning the lift at same angle will be abou t the same with this difference in angle=0A=0A=0A=0A=0A=0A=0A=0AThe chord l ine is just a reference line that is convenient to draw and measure, but ae rodynamically it is almost a fictive line, the important line or angle of a n airfoil is the zero lift angle, from this line the lift is generated if i t is given an angle to the relative wind, think of an symmetric airfoil whe re the zero lift line and chord line is the same, and at alpha zero it will not produce any=0Alift.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AAn airfoi l with camber will produce lift even if the chord line is at alpha zero, or slightly negative, because the zero lift line will have a positive alpha t o the wind.=0A=0A=0A=0ATo make a cambered airfoil to produce zero lift, the nose have to be lowered until the zero lift line is parallel to the wind, so an cambered airfoil is said to have a zero lift angle of minus some degr ee depending of the camber, it can be -1 to -6 degree on common airfoils an d camber.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe NACA 63A -215 have a zero lift angle of -1.64 degree, and the Riblett GA-37A315 -2.1 4 degree.=0A=0A=0A=0AA difference of 0.50 degree.=0A=0A=0A=0A=0A=0A=0A=0ATh e lift slope Cl alpha=C2=B4 is depending on the wing aspect ratio, for a AR of 6, the slope of the lift curve is CL=C2=B5 = 2Phi / 1+2/A2 = 2Phi / 1 + 2 / 6 = 4.71239 per radian=0A=0A=0A=0AOr=0A4.71239 / 57.3 = 0.0822 4 per degree=0A=0A=0A=0A=0A=0A=0A=0AThe original wing is 3 degree up from c hord line to fuselage reference line, so if we fly it with the reference li ne horizontal the wing CL=C2- =C2- is 3 - -1.64 = 4.64 degree a 0,082 24 = 0,38 CL.=0A=0A=0A=0A=0A=0A=0A=0AThe GA-37A315 will be 1 degree less measured at the chord line, so 2 - -2.14 = 4.14. so CL with fuselage leve l will be 0.34=0A=0A=0A=0AIt means that at higher speeds the nose down angl e will be 0.5 degree less.=0A=0A=0A=0A=0A=0A=0A=0ALets say we cruse at 165 MPH TAS @ 8000=C2=B4 and 1450 Lb the CL will be 0.30 plus the fact that the wing have to carry the down force from tail plane. Both airfoils have a ne gative pitch moment of 0.05, the Riblett just a little more then the NACA d ue to more camber.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AThe load at the tail is its moment times the wing chord and area, times dynamic pressure.=0A=0A=0A=0AD ivided with=0Atail length.=0A=0A=0A=0AIt will be about 84-85 lb down force at cruise if CG is at 25% chord=0A=0A=0A=0ASo the wing then will carry 1535 lb or CL=C2- 0.32=0A=0A=0A=0A=0A=0A=0A=0AA CG further back will reduce n egative lift and then reduce induced drag. (And reversed.)=0A=0A=0A=0A1450 lb at after limit will reduce down force at the tail with 10 lb=0A=0A=0A=0A at forward limit it will ad 35 lb to a total lift the wing have to do of 15 70 lb or CL 0.33=0A=0A=0A=0A=0A=0A=0A=0AA CG to forward and the elevator wi ll not be able to hold the nose up with flaps, to far back and it will be s ensitive on the stick. Then we come into:=0A=0A=0A=0A=0A=0A=0A=0ANose drop at landing, sounds like ground effect, when closer to ground the down wash from wing is flattened out, meaning the tail will have less down force.=0A =0A=0A=0AWith a horizontal stab area of just a bit over 17% of the wing are a, seems small, even if the tail arm=0Ais long.=0A=0A=0A=0AOne reason for t he elevator not be up to the job can also be the tail incidence, 0.5 - 0.75 degree down might help.=C2- (but hard to fix that now)=0A=0A=0A=0ASeems like, longer elevators chords is a good thing, 1,75=9D longer chord m ove the hinge line to 60% chord/40% elevator.=C2- (about =9Cnormal =9D)=0A=0A=0A=0AAnd VG's, seems to help, it means something is wrong from start, to small elevator or wrong incidence. Or to small H.- tail area or all three.=0A=0A=0A=0A=0A=0A=0A=0AThe Wing =93 Fuselage fairing s hould be expanding and 10% of the chord at the trailing edge, according to Raymer, It mean in my eyes it should be 10% of the local chord, so mid chor d it is 5% of the total chord length.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A =0A=0AI don=99t see anyone on Matronics talks about if they sealed th e control surface hinge gaps with tape. That will make a big difference. Ta pe them with Tesa fabric tape=0Aon the bottom side of the Hinge line, insid e the elevator, inside the rudder, inside the aileron, and bottom of the fl ap hinge line.=0A=0A=0A=0A=0A=0A=0A=0A=0A=0AHaving them unsealed=C2- is l ike driving with the parking brake on.=0A=0A=0A=0AOn a Kitfox it is the dif ference of being able to make a 3-point or not with or without sealing the elevator gap.=0A=0A=0A=0A=0A=0A=0A=0AJan Carlsson=0A=0A=0A=0AJC Propeller D esign=0A=0A=0A=0A=0A=0A=0A=0APs. Sorry to say, I have never been onboard a KIS.=0A=0A=0A=0A=0A=0A=0A=0A--------=0A=0A=0A=0Awww.jcpropellerdesign.com =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0ARead this topic online here:=0A=0A=0A=0A=0A=0A=0A=0Ahttp://forums.matronics.com/viewtopic. php?p=392088#392088=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A =0A=0AAttachments:=0A=0A=0A=0A=0A=0A=0A=0Ahttp://forums.matronics.com//file s/63a215_37a315_le_rad_133.jpg=0A=0A=0A=0Ahttp://forums.matronics.com//file s/63a215_37a315_184.jpg=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A =0A=0A=0A============0A=0A=0A=0Arget="_blank">http: //www.matronics.com/Navigator?KIS-List=0A=0A=0A=0A======== ====0A=0A=0A=0Ahttp://forums.matronics.com/=0A=0A=0A=0A==== ========0A=0A=0A=0Ale, List=0AAdmin.=0A=0A=0A=0A="_blank">h ttp://www.matronics.com/contribution=0A=0A=0A=0A========= ===0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A =0A=0A=0A=0A=0A=0A=0A============0A=0Arget="_blank" >http://www.matronics.com/Navigator?KIS-List=0A=0A======== ====0A=0Ahttp://forums.matronics.com/=0A=0A======== ====0A=0Ale, List Admin.=0A=0A="_blank">http://www.matronics.com/co ntribution=0A=0A============0A=0A=0A=0A=0A
="" http://www.====== ================/=0A=0A=0A=0A=0A=0A=C2- - =C2- =C2- =C2- =C2- =C2- =C2- =C2- -Matt Dralle, List Adm ====== ________________________________ Message 7 _____________________________________ Time: 07:47:20 PM PST US From: Scott Stearns Subject: Re: KIS-List: KIS TR-1 Airfoil Hi Jesse,=0A=C2-=0AMark's numbers are based on part 23 certified airplane loads.=C2- Which means a 100 pound push/pull on the control stick.=C2- I doubt I have or will ever pull more than 20 pounds on my stick.=C2-=C2 - If I were designing an airplane I would use part 23 control loads, but it probably isn't anything to lose sleep over in our kisi.=0A=C2-=0AScott =0A =0A=0A________________________________=0A From: "Flyinisfun@aol.com" =0ATo: kis-list@matronics.com =0ASent: Monday, January 14 , 2013 6:08 PM=0ASubject: Re: KIS-List: KIS TR-1 Airfoil=0A =0A=0A =0AThis is Jesse, =0AI built and used the materials that came with the kit.=C2- I achieved the =0Adegrees of up elevator called for=C2-in the prints.=C2 - How close the down =0Aarm from the elevator comes to hitting something I don't know now.=C2-"I'm =0Asurprised these problems didn't surface befo re now.=C2- Maybe they did and I =0Amissed them, which is it?=C2- I'm a ssuming we're still talking about the =0ATR-1. =0A=0A=0A=0AIn a message dat ed 1/14/2013 6:49:26 P.M. Mountain Standard Time, =0Amantafs@earthlink.net writes: =0A--> KIS-List message posted by: Mark Kettering =0A>=0A>The current aft elevator tube is 6061 T6, =0A 120" long, 1 .25" dia, 0.065" wall with a margin of safety of -0.39.=C2- FYI, =0A the forward steel tube is 4130, 51.25" long, 0.74" dia, 0.035" wall with a =0A margin of safety of -0.35.=C2- The margin of safety must be positive to be =0A safe.=0A>=0A>Steel or aluminum is a wash for weight to stiffness r atio.=C2- =0A But for the long elevator tube to be 1" dia steel it would need to be 0.075 =0A wall or thicker.=C2- This would make it over 6 tim es more heavy than the =0A aluminum tube (about 10 lbs more) and only give you 0.125" more clearance on =0A the horizontal.=C2- Diameter really he lps for tube compression buckling =0A resistance.=0A>=0A>Using two tubes r eally reduces the load.=C2- If 2 tubes =0A were used and they were each 60" long they could be 6061 T6, 1" dia, 0.058" =0A wall and still have a 0 .11 margin of safety.=0A>=0A>As Scott said, double =0A tapered would reall y help.=0A>=0A>I think the most simple solution is to =0A increase the len gth of the rudder control horn (from 4' to 5") and slightly =0A change the idler ratio (change the long side to 5").=C2- Not only does this =0A in crease the clearance but it also reduces the load on the push tube.=C2- =0A Still not a positive margin but only about half as =0A negative.=0A> =0A>Mark=0A>=0A>-----Original Message-----=0A>=0A>From: Scott =0A Stearns =0A>=0A>Sent: Jan 14, 2013 4:37 PM=0A>=0A>To: "kis-list@matronics.com" =0A> =0A>Subject: Re: KIS-List: KIS TR-1 Airfoil=0A>=0A>=0A>=0A>Another option =0A would be to make a reducer fitting and transition to a smaller tube fo r the =0A portion that goes under the horizontal.=C2- An ideal push tube is tapered =0A and you only need the full diameter at the center.=C2- T he fantasy push tube =0A is tapered unidirectional boron fiber. Can someon e post the tube length and =0A diameter/wall thickness and the distance fr om the LE of the horizontal tail to =0A the point where the tube bolts to the elevator? Another option is to switch =0A the whole tube to a smaller diameter steel tube.=C2- It would be the easiest =0A solution, but it wo uld add some wieght.=C2- 3-4 pounds probably.=C2-=C2- =0A My=0A>forw ard pitch control tube is 3/4" diameter steel on my much modified =0A TR-1 to minimize the width of the center console.=C2- Scott=0A>=C2- =C2- =0A =C2- =C2- From: Mark Kettering =0A>To: =0A kis-list@matronics.com =0A>Sent: Monday, January 14, 2013 12:43 PM=0A>Subj ect: =0A Re: KIS-List:=0A>KIS TR-1 Airfoil=0A>=C2-=C2- =0A>=0A>--> KIS -List =0A message posted by: Mark Kettering =0A =0A>=0A>>From my calculations when I worked =0A for Tri-R, the elevator pu sh pull tube was undersized for it's length.=C2- =0A Then talking with V ance it came up that the up throw was well less than =0A calculated due to contact between the push tube and horizontal.=C2- The =0A solution talk ed about was to put an additional idler well aft in the fuselage =0A and a s low as possible and then the most aft tube would no longer contact the =0A horizontal.=C2- This would solve two issues at the same time.=0A>=0A >I also =0A like the idea of increasing the length of the control arm on t he elevator and =0A changing the ratio on the current idler.=C2- This wo uld reduce the load on =0A the push tube and increase the clearance from t he tube to the =0A horizontal.=0A>=0A>Mark=0A>=0A>-----Original Message--- --=0A>=0A>From: Galin =0A Hernandez=0A>=0A>=0A>Sent: Jan 13, 2013 10:34 PM =0A>=0A>To: =0A kis-list@matronics.com=0A>=0A>Subject: Re: KIS-List: KIS T R-1 =0A Airfoil=0A>=0A>=0A>=0A>As far as I can tell it is stock as per the plans. =0A Maybe that is why the VG's made a significant difference. Gali n=0A>=0A>On Sun, =0A Jan 13, 2013 at 2:12 PM, Mark Kettering =0A>=0A>=0A>=0A>=0A>=0A>Hello =0A Galin, =0A>=0A>=0A>=0A>Is your elevator linkage stock as per the plans or =0A mod ified to allow for more up elevator?=C2- I think this modification is =0A very important and may prevent the need for VG's.=C2- The stock method had =0A the control tube hit the bottom of=0A>the horizontal inside the ta il before a =0A reasonable up elevator deflection limit could be =0A reac hed.=0A>=0A>=0A>=0A>=0A>=0A>Mark=0A>=0A>=0A>=0A>=0A>=0A>-----Original =0A Message-----=0A>=0A>=0A>=0A>From: Galin Hernandez=0A>=0A>=0A>=0A>Sent: Jan 13, =0A 2013 10:20 AM=0A>=0A>=0A>=0A>To: =0A kis-list@matronics.com=0A> =0A>=0A>=0A>Subject: Re: KIS-List: KIS TR-1 =0A Airfoil=0A>=0A>=0A>=0A>=0A >=0A>=0A>=0A>Jan; What do you mean when you say =0A "Tape them with Tesa f abric tape on the bottom side of the Hinge line, inside =0A the elevator, inside the rudder, inside the aileron, and bottom of the flap =0A hinge li ne." Can you provide a photo of what you mean? This sounds like a =0A viab le option for those of us that have flying airplanes and can't re-work the =0A wing/tail.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>I used the VG's from Stolspe ed.com =0A on the elevator and they=0A>made a significant improvement whil e landing my =0A TR-4.=0A>=0A>GalinN819PR=0A>=0A>=0A>=0A>On Fri, Jan 11, 2 013 at 4:36 PM, =0A Propellerjan =0A wrote:=0A =0A =0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> =0A>KIS =0A TR-1 Airfoil=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>In the search for information to =0A calculate an optimum propeller for the KIS I0-240 I fou nd a lot of information =0A and thoughts about its handling especially dur ing =0A landing.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>When picking an airfoil fo r a airplane =0A project that is about the last thing to do before the des ign is set in stone. =0A The wing area is determined in respect of stall s peed with flap =0A arrangement.=0A>=0A>=0A>=0A>When=0A>having MTOW, wing a spect ratio and wing =0A area, we can calculate speed and lift coefficient , =0A CL=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>The speed we use for this will be where we =0A spend most of the time, not stall speed and not top speed, bu t climb and =0A normal cruise speed. So in this range the airfoil should h ave the lowest drag, =0A if it was an airliner that spend most of its time climbing and cruising at =0A high altitude at low indicated speed it will be at similar CL most of the time =0A (but Mach Nr will play its =0A rol l)=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>All aircrafts =0A that see any production see an increase in installed power and weight. If this =0A was in the design of the KIS from start I don=99t know, bu t the prototype had a =0A Limbach from start if understand it correctly, a nd several hundred lbs less =0A weight.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A >=0A>=0A>=0A>=0A>=0A>Most seem to =0A have the I0-240B engine installed no w and a MTOW of 1450 lb or so. And it =0A is=0A>cruising at around 140 kts . This give an lift coefficient, of around CL =0A 0.3 at cruise, it mean t hat an airfoil with higher camber would have been =0A better then the curr ent N-63A215, where the 3:d last digit tell the designed =0A CL So it have an airfoil designed for higher speeds, but no meaning to have =0A that, n o one cruise at WOT at SL, but most cruise at 65-75% power from 2000=C2=B4 =0A to 8000 or 12000=C2=B4=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> =0A>=0A>The =0A NACA 6x- series isn=99t the best with today standard , rumour says that the NACA =0A screwed up when publishing these new airfo ils with a faulty design that they =0A could not take back.=0A>=0A>=0A>=0A >=0A>=0A>=0A>=0A>An Harry Riblett GA-37A315 =0A would be a better choice, it have gentler stall, and will show less drag at =0A both cruise and clim b, The difference between Riblett and NACA is that the =0A nose radii is p laced correctly on the Riblett. The Riblett will have about =0A 7-8% highe r=0A>CLmax.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>I =0A d raw up both airfoils for evaluation and when aligning the portion where mai n =0A and after spar will be, it is a different of 1 degree at the chord l ine. (From =0A nose radii to trailing =0A edge)=0A>=0A>=0A>=0A>=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>The NACA is in =0A Green=0A>=0A>=0A>=0A>=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>>From the main spar =0A and back there is very lit tle difference in shape, meaning the lift at same =0A angle will be about the same with this difference in =0A angle=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> The chord line is just a reference line =0A that is convenient to draw and measure, but aerodynamically it is almost a =0A fictive line, the importa nt line or angle of an airfoil is the zero lift =0A angle, from this line the lift is generated if it is given an angle to the =0A relative wind, th ink of an symmetric airfoil where the zero lift line and =0A chord line is the same, and at alpha zero it will not produce =0A any=0A>lift.=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>An airfoil =0A with camber will produce lift even if the chord line is at alpha zero, or =0A slightl y negative, because the zero lift line will have a positive alpha to =0A t he wind.=0A>=0A>=0A>=0A>To make a cambered airfoil to produce zero lift, th e =0A nose have to be lowered until the zero lift line is parallel to the wind, so =0A an cambered airfoil is said to have a zero lift angle of minu s some degree =0A depending of the camber, it can be -1 to -6 degree on co mmon airfoils and =0A camber.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>=0A>The =0A NACA 63A-215 have a zero lift angle of -1.64 degree, and the Riblett GA-37A315 =0A -2.14 degree.=0A>=0A>=0A>=0A> A difference of 0.50 =0A degree.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>The lift s lope Cl alpha=C2=B4 is depending =0A on the wing aspect ratio, for a AR of 6, the slope of the lift curve is CL=C2=B5 = =0A 2Phi / 1+2/A2 = 2Phi / 1 + 2 / 6 = 4.71239 per =0A radian=0A>=0A>=0A>=0A>Or=0A>4.71239 / 57. 3 = 0.08224 per =0A degree=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>The original w ing is 3 degree up from =0A chord line to fuselage reference line, so if w e fly it with the reference line =0A horizontal the wing CL=C2- =C2- i s 3 - -1.64 = 4.64 degree a 0,08224 = =0A 0,38 CL.=0A>=0A>=0A>=0A>=0A> =0A>=0A>=0A>The GA-37A315 will be 1 degree less =0A measured at the chord line, so 2 - -2.14 = 4.14. so CL with fuselage level =0A will be 0.34=0A >=0A>=0A>=0A>It means that at higher speeds the nose down angle =0A will b e 0.5 degree less.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>Lets say we cruse at =0A 165 MPH TAS @ 8000=C2=B4 and 1450 Lb the CL will be 0.30 plus the fact tha t the =0A wing have to carry the down force from tail plane. Both airfoils have a =0A negative pitch moment of 0.05, the Riblett just a little more then the NACA =0A due to more camber.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> =0A>The load at the =0A tail is its moment times the wing chord and area, times dynamic =0A pressure.=0A>=0A>=0A>=0A>Divided with=0A>tail length.=0A >=0A>=0A>=0A>It will =0A be about 84-85 lb down force at cruise if CG is a t 25% chord=0A>=0A>=0A>=0A>So =0A the wing then will carry 1535 lb or CL =C2- =0A 0.32=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>A CG further back will redu ce negative =0A lift and then reduce induced drag. (And reversed.)=0A>=0A> =0A>=0A>1450 lb at =0A after limit will reduce down force at the tail with 10 lb=0A>=0A>=0A>=0A>at =0A forward limit it will ad 35 lb to a total lif t the wing have to do of 1570 lb =0A or CL 0.33=0A>=0A>=0A>=0A>=0A>=0A>=0A >=0A>A CG to forward and the elevator =0A will not be able to hold the nos e up with flaps, to far back and it will be =0A sensitive on the stick. Th en we come into:=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>Nose =0A drop at landing, sounds like ground effect, when closer to ground the down =0A wash from wi ng is flattened out, meaning the tail will have less down =0A force.=0A> =0A>=0A>=0A>With a horizontal stab area of just a bit over 17% of =0A the wing area, seems small, even if the tail arm=0A>is =0A long.=0A>=0A>=0A> =0A>One reason for the elevator not be up to the job can also =0A be the t ail incidence, 0.5 - 0.75 degree down might help.=C2- (but hard to =0A f ix that now)=0A>=0A>=0A>=0A>Seems like, longer elevators chords is a good =0A thing, 1,75=9D longer chord move the hinge line to 60% chord/40% elevator.=C2- =0A (about =9Cnormal=9D)=0A>=0A>=0A>=0A>And V G's, seems to help, it means something is =0A wrong from start, to small e levator or wrong incidence. Or to small H.- tail =0A area or all three.=0A >=0A>=0A>=0A>=0A>=0A>=0A>=0A>The Wing =93 Fuselage fairing =0A shoul d be expanding and 10% of the chord at the trailing edge, according to =0A Raymer, It mean in my eyes it should be 10% of the local chord, so mid cho rd =0A it is 5% of the total chord =0A length.=0A>=0A>=0A>=0A>=0A>=0A>=0A >=0A>=0A>=0A>=0A>=0A>=0A>=0A>I don=99t see =0A anyone on Matronics t alks about if they sealed the control surface hinge gaps =0A with tape. Th at will make a big difference. Tape them with Tesa fabric =0A tape=0A>on t he bottom side of the Hinge line, inside the elevator, inside the =0A rudd er, inside the aileron, and bottom of the flap hinge =0A line.=0A>=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>=0A>Having them unsealed=C2- is =0A like driving with the parking brake on.=0A>=0A>=0A>=0A>On a Kitfox it is the =0A diffe rence of being able to make a 3-point or not with or without sealing the =0A elevator gap.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>Jan Carlsson=0A>=0A>=0A> =0A>JC =0A Propeller Design=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>Ps. Sorry to sa y, I have never =0A been onboard a =0A KIS.=0A>=0A>=0A>=0A>=0A>=0A>=0A> =0A>--------=0A>=0A>=0A>=0A>www.jcpropellerdesign.com=0A>=0A>=0A>=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>Read =0A this topic online =0A here:=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>http://forums.matron ics.com/viewtopic.php?p=392088#392088=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>Attachments:=0A>=0A>=0A>=0A>=0A >=0A>=0A>=0A>http://forums.matronics.com//files/63a215_37a315_le_rad_133.jp g=0A>=0A>=0A>=0A>http://forums.matronics.com//files/63a215_37a315_184.jpg =0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A >=0A>============0A>=0A>=0A>=0A>rget="_blank">http: //www.matronics.com/Navigator?KIS-List=0A>=0A>=0A>=0A>======= =====0A>=0A>=0A>=0A>http://forums.matronics.com/=0A>=0A>=0A>=0A>= ===========0A>=0A>=0A>=0A>le, =0A List=0A>Admin.=0A> =0A>=0A>=0A>="_blank">http://www.matronics.com/contribution=0A>=0A>=0A> =0A>============0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> =0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A >=0A>=0A>============0A>=0A>rget="_blank">http://ww w.matronics.com/Navigator?KIS-List=0A>=0A>=========== =0A>=0A>http://forums.matronics.com/=0A>=0A>========== ==0A>=0A>le, =0A List =0A Admin.=0A>=0A>="_blank">http://www.matronic s.com/contribution=0A>=0A>============0A>=0A>=0A>=0A> =0A>=0A>="" =0A http://www.=============== ========0A>=0A>=0A>=0A>=0A>=0A>=C2- =C2- =0A =0Aies =0Aay =0A =C2- =C2- =C2- =C2- =C2- =C2-=C2- - MATRONICS WEB FORUM S =0A =C2- =C2- =C2- =C2- =C2-=C2- - List Contribution Web Sit e =0Ap; =C2- =0A =C2- =C2- =C2- =C2- =C2- =C2- =C2- =C2- =========================0A =========================0A ======================= ________________________________ Message 8 _____________________________________ Time: 07:53:00 PM PST US From: Flyinisfun@aol.com Subject: Re: KIS-List: KIS TR-1 Airfoil Thanks Mark, I'm going to bed and get a good nights sleep. Jesse In a message dated 1/14/2013 8:47:24 P.M. Mountain Standard Time, sstearns2@yahoo.com writes: Hi Jesse, Mark's numbers are based on part 23 certified airplane loads. Which means a 100 pound push/pull on the control stick. I doubt I have or will ever pull more than 20 pounds on my stick. If I were designing an airplane I would use part 23 control loads, but it probably isn't anything to lose sl eep over in our kisi. Scott From: "Flyinisfun@aol.com" Sent: Monday, January 14, 2013 6:08 PM Subject: Re: KIS-List: KIS TR-1 Airfoil This is Jesse, I built and used the materials that came with the kit. I achieved the degrees of up elevator called for in the prints. How close the down arm f rom the elevator comes to hitting something I don't know now. "I'm surprised these problems didn't surface before now. Maybe they did and I missed the m, which is it? I'm assuming we're still talking about the TR-1. In a message dated 1/14/2013 6:49:26 P.M. Mountain Standard Time, mantafs@earthlink.net writes: --> KIS-List message posted by: Mark Kettering The current aft elevator tube is 6061 T6, 120" long, 1.25" dia, 0.065" wall with a margin of safety of -0.39. FYI, the forward steel tube is 413 0, 51.25" long, 0.74" dia, 0.035" wall with a margin of safety of -0.35. The margin of safety must be positive to be safe. Steel or aluminum is a wash for weight to stiffness ratio. But for the long elevator tube to be 1" dia steel it would need to be 0.075 wall or thicker. This would make it over 6 times more heavy than the aluminum tub e (about 10 lbs more) and only give you 0.125" more clearance on the horizon tal. Diameter really helps for tube compression buckling resistance. Using two tubes really reduces the load. If 2 tubes were used and they were each 60" long they could be 6061 T6, 1" dia, 0.058" wall and still ha ve a 0.11 margin of safety. As Scott said, double tapered would really help. I think the most simple solution is to increase the length of the rudder control horn (from 4' to 5") and slightly change the idler ratio (change th e long side to 5"). Not only does this increase the clearance but it also reduces the load on the push tube. Still not a positive margin but only about half as negative. Mark -----Original Message----- From: Scott Stearns Sent: Jan 14, 2013 4:37 PM Subject: Re: KIS-List: KIS TR-1 Airfoil Another option would be to make a reducer fitting and transition to a smaller tube for the portion that goes under the horizontal. An ideal pus h tube is tapered and you only need the full diameter at the center. The fantasy push tube is tapered unidirectional boron fiber. Can someone post the tube length and diameter/wall thickness and the distance from the LE of th e horizontal tail to the point where the tube bolts to the elevator? Another option is to switch the whole tube to a smaller diameter steel tube. It would be the easiest solution, but it would add some wieght. 3-4 pounds probably. My forward pitch control tube is 3/4" diameter steel on my much modified TR-1 to minimize the width of the center console. Scott From: Mark Kettering Sent: Monday, January 14, 2013 12:43 PM Subject: Re: KIS-List: KIS TR-1 Airfoil >From my calculations when I worked for Tri-R, the elevator push pull tube was undersized for it's length. Then talking with Vance it came up that the up throw was well less than calculated due to contact between the push tube and horizontal. The solution talked about was to put an additional idler well aft in the fuselage and as low as possible and then the most af t tube would no longer contact the horizontal. This would solve two issues at the same time. I also like the idea of increasing the length of the control arm on the elevator and changing the ratio on the current idler. This would reduce t he load on the push tube and increase the clearance from the tube to the horizontal. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:34 PM Subject: Re: KIS-List: KIS TR-1 Airfoil As far as I can tell it is stock as per the plans. Maybe that is why the VG's made a significant difference. Galin On Sun, Jan 13, 2013 at 2:12 PM, Mark Kettering wrote: --> KIS-List message posted by: Mark Kettering Hello Galin, Is your elevator linkage stock as per the plans or modified to allow for more up elevator? I think this modification is very important and may prevent the need for VG's. The stock method had the control tube hit the bottom of the horizontal inside the tail before a reasonable up elevator deflection limit could be reached. Mark -----Original Message----- From: Galin Hernandez Sent: Jan 13, 2013 10:20 AM Subject: Re: KIS-List: KIS TR-1 Airfoil Jan; What do you mean when you say "Tape them with Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line." Can you provide a photo of what you mean? This sounds like a viable option for those of us t hat have flying airplanes and can't re-work the wing/tail. I used the VG's from Stolspeed.com on the elevator and they made a significant improvement while landing my TR-4. GalinN819PR On Fri, Jan 11, 2013 at 4:36 PM, Propellerjan wrote: KIS TR-1 Airfoil In the search for information to calculate an optimum propeller for the KIS I0-240 I found a lot of information and thoughts about its handling especially during landing. When picking an airfoil for a airplane project that is about the last thing to do before the design is set in stone. The wing area is determined in respect of stall speed with flap arrangement. When having MTOW, wing aspect ratio and wing area, we can calculate speed and lift coefficient, CL The speed we use for this will be where we spend most of the time, not stall speed and not top speed, but climb and normal cruise speed. So in th is range the airfoil should have the lowest drag, if it was an airliner that spend most of its time climbing and cruising at high altitude at low indicated speed it will be at similar CL most of the time (but Mach Nr wil l play its roll) All aircrafts that see any production see an increase in installed power and weight. If this was in the design of the KIS from start I don=99 t know, but the prototype had a Limbach from start if understand it correctly, and several hundred lbs less weight. Most seem to have the I0-240B engine installed now and a MTOW of 1450 lb or so. And it is cruising at around 140 kts. This give an lift coefficient, of around CL 0.3 at cruise, it mean that an airfoil with higher camber would have been better then the current N-63A215, where the 3:d last digit tell the design ed CL So it have an airfoil designed for higher speeds, but no meaning to hav e that, no one cruise at WOT at SL, but most cruise at 65-75% power from 2000=C2=B4 to 8000 or 12000=C2=B4 The NACA 6x- series isn=99t the best with today standard, rumour say s that the NACA screwed up when publishing these new airfoils with a faulty desig n that they could not take back. An Harry Riblett GA-37A315 would be a better choice, it have gentler stall, and will show less drag at both cruise and climb, The difference be tween Riblett and NACA is that the nose radii is placed correctly on the Riblett . The Riblett will have about 7-8% higher CLmax. I draw up both airfoils for evaluation and when aligning the portion where main and after spar will be, it is a different of 1 degree at the chord line. (>From nose radii to trailing edge) The NACA is in Green >From the main spar and back there is very little difference in shape, meaning the lift at same angle will be about the same with this difference in angle The chord line is just a reference line that is convenient to draw and measure, but aerodynamically it is almost a fictive line, the important li ne or angle of an airfoil is the zero lift angle, from this line the lift is generated if it is given an angle to the relative wind, think of an symmet ric airfoil where the zero lift line and chord line is the same, and at alpha zero it will not produce any lift. An airfoil with camber will produce lift even if the chord line is at alpha zero, or slightly negative, because the zero lift line will have a positive alpha to the wind. To make a cambered airfoil to produce zero lift, the nose have to be lowered until the zero lift line is parallel to the wind, so an cambered a irfoil is said to have a zero lift angle of minus some degree depending of the camber, it can be -1 to -6 degree on common airfoils and camber. The NACA 63A-215 have a zero lift angle of -1.64 degree, and the Riblett GA-37A315 -2.14 degree. A difference of 0.50 degree. The lift slope Cl alpha=C2=B4 is depending on the wing aspect ratio, for a AR of 6, the slope of the lift curve is CL=C2=B5 = 2Phi / 1+2/A2 = 2Phi / 1 + 2 / 6 = 4.71239 per radian Or 4.71239 / 57.3 = 0.08224 per degree The original wing is 3 degree up from chord line to fuselage reference line, so if we fly it with the reference line horizontal the wing CL is 3 - -1.64 = 4.64 degree a 0,08224 = 0,38 CL. The GA-37A315 will be 1 degree less measured at the chord line, so 2 - -2.14 = 4.14. so CL with fuselage level will be 0.34 It means that at higher speeds the nose down angle will be 0.5 degree less. Lets say we cruse at 165 MPH TAS @ 8000=C2=B4 and 1450 Lb the CL will be 0 .30 plus the fact that the wing have to carry the down force from tail plane. Both airfoils have a negative pitch moment of 0.05, the Riblett just a lit tle more then the NACA due to more camber. The load at the tail is its moment times the wing chord and area, times dynamic pressure. Divided with tail length. It will be about 84-85 lb down force at cruise if CG is at 25% chord So the wing then will carry 1535 lb or CL 0.32 A CG further back will reduce negative lift and then reduce induced drag. (And reversed.) 1450 lb at after limit will reduce down force at the tail with 10 lb at forward limit it will ad 35 lb to a total lift the wing have to do of 1570 lb or CL 0.33 A CG to forward and the elevator will not be able to hold the nose up with flaps, to far back and it will be sensitive on the stick. Then we come into: Nose drop at landing, sounds like ground effect, when closer to ground the down wash from wing is flattened out, meaning the tail will have less down force. With a horizontal stab area of just a bit over 17% of the wing area, seems small, even if the tail arm is long. One reason for the elevator not be up to the job can also be the tail incidence, 0.5 - 0.75 degree down might help. (but hard to fix that now) Seems like, longer elevators chords is a good thing, 1,75=9D longer chord move the hinge line to 60% chord/40% elevator. (about =9Cnormal =9D) And VG's, seems to help, it means something is wrong from start, to small elevator or wrong incidence. Or to small H.- tail area or all three. The Wing =93 Fuselage fairing should be expanding and 10% of the cho rd at the trailing edge, according to Raymer, It mean in my eyes it should be 10 % of the local chord, so mid chord it is 5% of the total chord length. I don=99t see anyone on Matronics talks about if they sealed the con trol surface hinge gaps with tape. That will make a big difference. Tape them w ith Tesa fabric tape on the bottom side of the Hinge line, inside the elevator, inside the rudder, inside the aileron, and bottom of the flap hinge line. Having them unsealed is like driving with the parking brake on. On a Kitfox it is the difference of being able to make a 3-point or not with or without sealing the elevator gap. Jan Carlsson JC Propeller Design Ps. Sorry to say, I have never been onboard a KIS. -------- www.jcpropellerdesign.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=392088#392088 Attachments: http://forums.matronics.com//files/63a215_37a315_le_rad_133.jpg http://forums.matronics.com//files/63a215_37a315_184.jpg rget="_blank">http://www.matronics.com/Navigator?KIS-List http://forums.matronics.com/ le, List Admin. ="_blank">http://www.matronics.com/contribution rget="_blank">http://www.matronics.com/Navigator?KIS-List http://forums.matronics.com/ le, List Admin. ="_blank">http://www.matronics.com/contribution ="" http://www.=================== == ies ay - MATRONICS WEB FORUMS - List Contribution Web Site p; http://www.matronics.com/Navigator?KISom/" rel="nofollow" target="_blank">http://forums.matronics.com/ ef="http://www.matronics.com/contribution" rel="nofollow" target="_bl == (http://www.matronics.com/Navigator?KIS-List) (http://www.matronics.com/contribution) ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kis-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/KIS-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/kis-list Browse Digests http://www.matronics.com/digest/kis-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.