---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Sat 04/14/12: 6 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:29 AM - Re: Re: Pitot Static (jimpuglise@comcast.net) 2. 07:37 AM - Re: Re: Pitot Static (Jan de Jong) 3. 10:53 AM - Re: Approach and Landing Speeds (Carl Meek) 4. 12:35 PM - Re: Approach and Landing Speeds (David Joyce) 5. 03:08 PM - Trailer (AirEupora) 6. 03:36 PM - Re: Trailer (Carl Meek) ________________________________ Message 1 _____________________________________ Time: 07:29:41 AM PST US From: jimpuglise@comcast.net Subject: Re: Europa-List: Re: Pitot Static Kevin- Will give you a better answer later in the day. I want to go to the airport and look at it. I am using my Dynon ASI only at this time. The ASA is fine. To calibrate the AOA, you need to do at least 3 stalls and I am still busy trying to get my overheating problems straightened out. I'll calibrate it after that. I don't find that flying without a stall warning is a problem. As long as you watch your speeds in the pattern, everything works fine. Will get you an answer later in the day. Jim ----- Original Message ----- From: "klinefelter kevin" Sent: Friday, April 13, 2012 8:47:17 PM Subject: Re: Europa-List: Re: Pitot Static Hi Jim, Do you think that mounting location will work well for the Dynon AOA? Is yours working well? In other words, is this worth doing? Thanks, Kevin Mono 914, 400hrs On Apr 13, 2012, at 2:47 PM, jimpuglise@comcast.net wrote: Kevin- Given the length and size of the Gretz fixture, that would be a lot of stress on a small area surrounding the access cover. You might be able to reinforce around it, but in my install, I used 1/16 plywood and two layers of BID about 12 inches square. Jim Puglise N283JL ----- Original Message ----- From: "klinefelter kevin" < klinefelter.kevin@gmail.com > Sent: Friday, April 13, 2012 12:08:37 PM Subject: Re: Europa-List: Re: Pitot Static Hi All, I'm thinking about adding Angle of Attack function to my Dynon D10a unit. This requires the Dynon aoa pitot to be installed on my completed wing. I think that could be done easily by mounting the pitot on the bellcrank access cover. Has anyone done this successfully? thanks, Kevin Mono 914, 400hrs On Mar 31, 2012, at 1:09 PM, jimpuglise@comcast.net wrote:
Paul- I mounted my Dynon on the same wing as the Europa probe. It mounts a little more toward the leading edge as I recall. I think I mounted mine just behind the spar. If you have closed your wings, you would need to put a hole in your skin to mount it, and do as Bud said and use the Gretz mount. I backed my Gretz mount with 1/16 plywood and BID. I put them in the same wing to avoid putting a run of irrigation tubing in the other wing also. The four tubes share a length of tubing to the wing root. I actually had to change the tubing and was able to get to it through the inspection port and do it in only an hour or so. I used a "T" connector to use the Europa static port for the Dynon also. Works fine. I have photos of it all if you need them. Jim Puglise N283JL -- 15 hrs and fighting cooling devils ----- Original Message ----- From: "Bud Yerly" < budyerly@msn.com > Sent: Thursday, March 29, 2012 9:39:28 PM Subject: Re: Europa-List: Re: Pitot Static Paul, I always put the standard pitot / static on my aircraft. It hooks to the normal A/S and Altimeter. The Dynon probe is added to the other wing normally and feeds the Dynon pitot/aoa. I make a 5 inch access hole and build in a flange then mount the probe and its Gretz mount to the wing about 10 inches back from the leading edge as that is what Dynon recommends I believe for its AOA function. Should icing be a consideration, I mount a cockpit static valve to use the cockpit air which is accurate to about 2 knots and 50 feet at all speeds and altitudes to 10,000 ft. Do not mount the Dynon where the standard pitot is. Regards, Bud
----- Original Message ----- From: Europaul383 Sent: Wednesday, March 28, 2012 2:47 PM Subject: Europa-List: Re: Pitot Static Hi Bud (or anyone else who has an answer), I read your post while looking for info on the Dynon AoA. I was thinking of installing this AoA, but their probe has just 2 holes - pitot and AoA - I'd then have to find another source for the static air - can you recall what George Reed did for static? Thanks in advance. Paul XS Mono 383 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=369480#369480 http://www.matronnbsp ; via the Web title= http://forums.matronics.com/ href=" http://forums.matronics.com "> http://forums.matronics.com _p; generous bsp; title= http://www.matronics.com/contribution href=" http://www.matronics.com/contribution "> http://www.matronics.com/c================= arget="_blank"> http://www.matronics.com/Navigator?Europa-List tp://forums.matronics.com _blank"> http://www.matronics.com/contribution ========= tp://www.matronics.com/Navigator?Europa-List ========== cs.com ========== matronics.com/contribution ==========
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________________________________ Message 2 _____________________________________ Time: 07:37:14 AM PST US From: Jan de Jong Subject: Re: Europa-List: Re: Pitot Static Hi Bob, > A question for anyone . > > Does the Europa stall warner wing inlet have any use in Angle of Attack instrumentation? > I don't think so. The pressure signal provided is designed to be very alinear: a small positive pressure (reference static) at most angles of attack, then a large negative pressure (reference static) near the stall angle. The purpose is to operate a switch. An AoA instrument using the signal would probably become just a stall warner too. I actually put a stall warning probe in the other wing with the intention of using it for an angle of attack measurement some time in the future. The orifice is at 4% of chord or so on the top surface. I had forgotten what the plans were exactly but I think I have documented now what my thoughts may have been. See the attachment. Jan de Jong AoA - calculated as percentage of maximum lift coefficient determine also: - current airspeed - stall speed at current mass and acceleration - reserve airspeed at current mass and acceleration additionally (after extra calibration inputs): - current lift as % of MTOW and after averaging: - mass as % of MTOW - manoeuvring speed uses a microcontroller measure q': differential pressure pitot and static p: differential pressure AoA-orifice and static correction the dynamic pressure at stall is an important ingredient it is probably necessary to correct q' for pitot position and angle to get a good value correction depends on AoA more than q' - may involve iteration assume succesfully done q: dynamic pressure airspeed q = k1 x (v-squared) k1 is a known constant v is calculated and indicated as airspeed percentage of maximum lift coefficient lift = k2 x l x q l is lift coefficient k2 is an unknown constant that depends on airplane/wings configuration and size calling L the maximum lift coefficient and Q the dynamic pressure at stall speed: lift = k2 x L x Q it follows that for any particular lift: 100 x l / L = 100 x Q / q, percentage of maximum lift coefficient (lift coefficient and dynamic pressure are inversely proportional) a function of lift coefficient with all things equal except airspeed and AoA we posit: p = f(l) x q where f(l) is a function of l only the underlying assumption is: - over the airspeed range of interest - around the location of the AoA-orifice the shape of the airflow (and the shape of the pressure distribution) does not depend on airspeed two-way function, locating an AoA-orifice the location of the AoA-orifice is selected so that f(l) is a strictly monotonic function of l over the whole range of positive AoA there must be a 1:1 relationship between f(l) and l, that gives good resolution in both directions over the whole range from NACA graphs it appears that an orifice in the wing top at a few % of chord should work (there are other probes and locations that may provide a good, strictly monotonic, signal) calibrating for a flight configuration (flaps position) 1. the airplane is repeatedly gently stalled register 2 numbers: f(l) = p / Q and 100; a maximum (or minimum) for f(l) is sought 2. select a higher airspeed, with the same lift (1 G) register 2 numbers: f(l) = p / q and 100 x Q / q 3. repeat for a number of airspeeds up to vne extra: register the current Q and put in and register: the current % of MTOW, the manoeuvring speed at MTOW according to the manual calculating lift coefficient percentage for a flight configuration (flaps position) determine f(l) as p / q, find percentage P (after interpolation) from the calibration table also: determine current Q from: q / Q = 100 x P determine current stall speed V from: Q = k1 x (V-squared) determine current reserve airspeed R from: R = v - V extra: find registered Q, % MTOW and manoeuvring speed, compare current Q to registered Q, calculate current % MTOW and manoeuvring speed ________________________________ Message 3 _____________________________________ Time: 10:53:03 AM PST US Subject: Re: Europa-List: Approach and Landing Speeds From: Carl Meek I just thought I'd report back on flying both last night (2 landings) and today (4 landings). Thanks to all the advice on the list, I'm feeling 500% more confident, and really happy with landing her. The technique I've settled on is basically 5kts slower than I was before, aiming for 60 over the fence, and then really holding it off until it just plops onto the runway. The final part of the equation to stop the front wheel bouncing up as we slow down is NOT to pull back on the elevator (literally only in the final slowing down bit). In my previous A/C I always held full back elevator when taxiing on grass, but this seems to make the europa too nose bouncy. In addition, keeping power on a bit longer than I Used to seems to help, I used to pretty much always shut off power at the 'over the fence' point but have now found that keeping a bit of thrust until the wheels are nearly down helps keep a nice controlled flare. Hopefully that's not all nonsense! Either way, 6 nice landings in 2 days is much better than the last 10 or so being less than satisfactory. Thanks for all the advice. Did anyone go to Duxford today? I heard a Europa inbound as I left around 3pm. On 13/04/2012 19:11, "Ivan Shaw" wrote: > >Through flight test find out what the indicated stall speed is at gross >weight and full flap of YOUR aircraft, then multiply this by 1.3, this is >your normal approach speed. >If it is gusty then add half the gust speed, if it is flat calm or a stead >breeze and you are light weight, [single place] then you can creeper it in >carrying a little power at minus five knots standard approach speed. >Practice at altitude flying in the landing configuration [full flap]at >your >standard approach speed and get used to the feel of the aircraft, >'recognize >the first nibble of a stall', do it until you are really COMFORTABLE, >practice rate one turns left and right keeping the ball centred. >Ideally practice on a long wide runway with clear approaches, take your >time >so you develop a 'feel' for the aircraft. >When you get it right the aircraft 'dies in your hand' one inch above your >chosen touch down point!!! But don't expect it too often! > >Regards >Ivan > >-----Original Message----- >From: owner-europa-list-server@matronics.com >[mailto:owner-europa-list-server@matronics.com] On Behalf Of Frans Veldman >Sent: 13 April 2012 14:47 >To: europa-list@matronics.com >Subject: Re: Europa-List: Approach and Landing Speeds > >--> > >On 04/13/2012 11:43 AM, Carl Meek wrote: > >> I've been typically flying short final at 70, over the fence at 65. >> However, I've found the float can be quite excessive > >A little bit of extra speed has a very markable influence on the flare. >Try a bit lower speed. If the stall characteristics of your ship are >benign, >there is nothing to worry about to get over the fence with 60, provided >there is no strong wind or thermal situation. > >> Frans, am I understanding you correctly that for a short field you >> actually come 'over the fence' and then retract the flaps before >> touching down? > >You can do that just before touching down, but the timing is critical. >If you to it too early you will get the opposite effect as you are taking >the drag of the flaps away. I usually start retracting the flaps just when >the airplane is about to settle down. This will take away the lift and >also >causes the wheels to have more grip on the ground, which is a good thing >if >you want to start braking immediately. > >This could be more interesting if the flaps could be operated much faster, >i.e. by hand rather than by a servo. Anyone an idea why the flaps where >made >electric on the tri-gear? > >I have to confess that I modified the flap gear slightly: I drilled a hole >in the arm of the torque tube just below the original hole, so the >leverage >to the servo is a bit less. This causes the flaps to extend 3 degrees >further and also speeds up the movement of the flaps. > >(If I understand the history of the Europa correctly, the flaps where >originally designed for 30 degrees, but the extension was limited to 27 >degrees after one found out that 30 degrees allows the mono to take off >earlier than control is achieved. In a tri-gear we don't have to worry too >much about this.) > >Frans > > ________________________________ Message 4 _____________________________________ Time: 12:35:52 PM PST US From: "David Joyce" Subject: Re: Europa-List: Approach and Landing Speeds Carl, Well done. I am afraid my contribution will not have helped. I managed to add 10 kts to what Imeant to say, which was down wind at 70, approach at 60kts and let it decay to 50 as you go over the fence assuming its a not too high fence! and holding it just off until it stops flying. Sounds as though that is pretty much what you are doing. Getting it trimmed precisely to 60 on the base leg or final (if a longish final) makes it much easier to get the rest right. Regards, David Joyce, G-XSDJ On Sat, 14 Apr 2012 18:50:19 +0100 Carl Meek wrote: > > > I just thought I'd report back on flying both last night >(2 landings) and > today (4 landings). Thanks to all the advice on the >list, I'm feeling > 500% more confident, and really happy with landing her. > The technique > I've settled on is basically 5kts slower than I was >before, aiming for 60 > over the fence, and then really holding it off until it >just plops onto > the runway. The final part of the equation to stop the >front wheel > bouncing up as we slow down is NOT to pull back on the >elevator (literally > only in the final slowing down bit). In my previous A/C >I always held > full back elevator when taxiing on grass, but this seems >to make the > europa too nose bouncy. In addition, keeping power on a >bit longer than I > Used to seems to help, I used to pretty much always shut >off power at the > 'over the fence' point but have now found that keeping a >bit of thrust > until the wheels are nearly down helps keep a nice >controlled flare. > > Hopefully that's not all nonsense! Either way, 6 nice >landings in 2 days > is much better than the last 10 or so being less than >satisfactory. > Thanks for all the advice. > > Did anyone go to Duxford today? I heard a Europa >inbound as I left around > 3pm. > > On 13/04/2012 19:11, "Ivan Shaw" > wrote: > >> >> >>Through flight test find out what the indicated stall >>speed is at gross >>weight and full flap of YOUR aircraft, then multiply this >>by 1.3, this is >>your normal approach speed. >>If it is gusty then add half the gust speed, if it is >>flat calm or a stead >>breeze and you are light weight, [single place] then you >>can creeper it in >>carrying a little power at minus five knots standard >>approach speed. >>Practice at altitude flying in the landing configuration >>[full flap]at >>your >>standard approach speed and get used to the feel of the >>aircraft, >>'recognize >>the first nibble of a stall', do it until you are really >>COMFORTABLE, >>practice rate one turns left and right keeping the ball >>centred. >>Ideally practice on a long wide runway with clear >>approaches, take your >>time >>so you develop a 'feel' for the aircraft. >>When you get it right the aircraft 'dies in your hand' >>one inch above your >>chosen touch down point!!! But don't expect it too often! >> >>Regards >>Ivan >> >>-----Original Message----- >>From: owner-europa-list-server@matronics.com >>[mailto:owner-europa-list-server@matronics.com] On Behalf >>Of Frans Veldman >>Sent: 13 April 2012 14:47 >>To: europa-list@matronics.com >>Subject: Re: Europa-List: Approach and Landing Speeds >> >>--> >> >>On 04/13/2012 11:43 AM, Carl Meek wrote: >> >>> I've been typically flying short final at 70, over the >>>fence at 65. >>> However, I've found the float can be quite excessive >> >>A little bit of extra speed has a very markable influence >>on the flare. >>Try a bit lower speed. If the stall characteristics of >>your ship are >>benign, >>there is nothing to worry about to get over the fence >>with 60, provided >>there is no strong wind or thermal situation. >> >>> Frans, am I understanding you correctly that for a short >>>field you >>> actually come 'over the fence' and then retract the >>>flaps before >>> touching down? >> >>You can do that just before touching down, but the timing >>is critical. >>If you to it too early you will get the opposite effect >>as you are taking >>the drag of the flaps away. I usually start retracting >>the flaps just when >>the airplane is about to settle down. This will take away >>the lift and >>also >>causes the wheels to have more grip on the ground, which >>is a good thing >>if >>you want to start braking immediately. >> >>This could be more interesting if the flaps could be >>operated much faster, >>i.e. by hand rather than by a servo. Anyone an idea why >>the flaps where >>made >>electric on the tri-gear? >> >>I have to confess that I modified the flap gear slightly: >>I drilled a hole >>in the arm of the torque tube just below the original >>hole, so the >>leverage >>to the servo is a bit less. This causes the flaps to >>extend 3 degrees >>further and also speeds up the movement of the flaps. >> >>(If I understand the history of the Europa correctly, the >>flaps where >>originally designed for 30 degrees, but the extension was >>limited to 27 >>degrees after one found out that 30 degrees allows the >>mono to take off >>earlier than control is achieved. In a tri-gear we don't >>have to worry too >>much about this.) >> >>Frans >> >> >> >> >> >> >> >> >> >> > > > >Un/Subscription, >Forums! >Admin. > > > ________________________________ Message 5 _____________________________________ Time: 03:08:35 PM PST US Subject: Europa-List: Trailer From: "AirEupora" I'm wondering about a trail for my Tri Gear here in the U.S. Has anybody made one? Are there any plans for one? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=370798#370798 Attachments: http://forums.matronics.com//files/img_0629_151.jpg ________________________________ Message 6 _____________________________________ Time: 03:36:01 PM PST US From: Carl Meek Subject: Re: Europa-List: Trailer I have a fantastic one made for me here in the Uk, I can send pictures and plans. Sent from my iPhone On 14 Apr 2012, at 23:05, "AirEupora" wrote: > > I'm wondering about a trail for my Tri Gear here in the U.S. Has anybody made one? Are there any plans for one? > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=370798#370798 > > > > > Attachments: > > http://forums.matronics.com//files/img_0629_151.jpg > > > > > > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message europa-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Europa-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/europa-list Browse Digests http://www.matronics.com/digest/europa-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.