---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Tue 01/30/07: 20 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:41 AM - Re: Landing Light Kit Assembly Grief () 2. 09:14 AM - Re: 601XL Wing Flutter (Gary Gower) 3. 09:30 AM - Re: Re: Wing flutter! (japhillipsga@aol.com) 4. 09:56 AM - Re: Re: 601XL Wing Flutter???? (Gary Gower) 5. 11:51 AM - FW: 601XL Wing Flutter (Meltonoso) 6. 01:48 PM - Re: Landing Light Kit Assembly Grief (Dave Ruddiman) 7. 02:20 PM - Re: Wing flutter! (Gig Giacona) 8. 02:24 PM - VGs feathers on an 801 (Keystone Engineering LLC) 9. 02:40 PM - Re: VGs feathers on an 801 (Dave Ruddiman) 10. 02:50 PM - Wing Flutter () 11. 03:01 PM - Re: VGs feathers on an 801 (JG) 12. 03:15 PM - Re: VGs feathers on an 801 (Dave Ruddiman) 13. 04:28 PM - Re: airplanes to compare to XL (Jennifer Moorhouse) 14. 04:33 PM - Re: Re: Spin 601xl any experience, caveates, unusual recovery techn (Juan Vega) 15. 04:38 PM - Re: Wing Flutter (John Fulp) 16. 04:57 PM - VGs feathers on an 801 (Keystone Engineering LLC) 17. 06:25 PM - vg feathers on an 801 () 18. 07:32 PM - Re: VGs feathers on an 801 (Dave Ruddiman) 19. 09:32 PM - Re: Spin 601xl any experience, caveates, unusual recovery techn (David X) 20. 09:37 PM - Re: 601XL Wing Flutter (David X) ________________________________ Message 1 _____________________________________ Time: 07:41:13 AM PST US From: Subject: Re: Zenith-List: Landing Light Kit Assembly Grief Alternative method: Go to dental school then after graduation, do root canals on upper second molars routinely for let's say..... 30 years or so. Makes assembling the landing lights look like shooting fish in a barrel (Does anyone actually shoot fish inside barrels? Why? What does PETA have to say about that practice? Does anyone care?) Sorry...... I had the right to remain silent......... but sadly, I lacked the discretion, Dred Please Do Not Archive Please take good care of those Second Molars ---- Brad DeMeo wrote: > I experienced a lot of grief trying to hold together the %$@#*! landing > light assembly while getting it fastened to the channel in the left > wing........ ________________________________ Message 2 _____________________________________ Time: 09:14:22 AM PST US From: Gary Gower Subject: Re: Zenith-List: 601XL Wing Flutter Hello all, Dont panic! This is simple severe turbulence by a big thermal. Normally a "bumpy" ride is not that way because in this case the heat is concetrated a lot. Like a fly flying over a torch welder :-) Just to make shure, lets remember, in the first signs of turbulence, slow a little the cruise speed, if it get severe, slow to manuver speed and keep alert not to get cought in a high angle attitude, "Ride" the turbulence with the controls as gently as possible... Saludos Gary Gower. Paul Mulwitz wrote: Hi Bill, That was a truly shocking story. I can't help but connect the dots with your flight and the recent events of XL's falling out of the sky. I wonder if you could answer a couple of questions: 1. Which aileron hinges do you have? 2. Do you have the center stick? 3. Did you build from kit or scratch? If you were actually experiencing flutter, then I would have thought slowing down would be the way out. When you increased speed to stop the vibration, did it occur again as you slowed down? I think I'll take up knitting instead of airplane building . .. Paul XL fuselage do not archive At 10:31 PM 1/26/2007, you wrote: Dear Thread Friends, I went flying this afternoon. Took a fellow with me and just wanted an hour in the clear blue. Conditions were perfect, clear, cool and only a slight wind. The only big thing around much to see nearby is Lake Juliette which has a big coal fired power station in the middle. Three huge steam towers that look like a nuclear power station. We flew around the lake about two miles away at 5000 feet so my pal could get a good look see. On the down wind side we flew into an invisible killer. We were doing above 140 when we flew into it. Instantly the left wing fluttered at a fast pitch, aileron and all and it looked to be moving maybe two inched up and down. I figured a couple seconds would break it off. I didn't have time to look around the passenger to see if the right wing was fluttering, but I suspect it was. I chopped power and did a hard diving wing over to the left and out of it. The flutter sound was great even over my Lightspeed AN system and the whole thing probably last maybe 5 or 6 seconds. I regained control out of the snap dive, maxing above 170 and flew slow and easy back to the field before I tested the controls. Everything felt okay and I could see no wrinkles in the top skin so I landed. Didn't really have much choice. Upon inspection I found no sign of stress, no skin deform, no paint cracked around rivets, nothing. I will take off all inspection panels for a close inspection this weekend and check bolts, controls, etc., but I cannot believe such a prolonged violent movement of the wing did not damage something other than my pride. Two things learned. Don't fly anywhere near a power station. Even at 5000 feet and miles away the invisible heat rises and is most extreme. Maybe intensified in cold weather. The other thing is the XL is very, very tough. Oh, there is a third thing. How could I have been so stupid not to know the first thing !! I am interested though in knowing why the wings fluttered in this thermal? What theory of air dynamics would cause this extreme reaction? Was is just the level of heat and speed the invisible air was streaming past? This was my 90th flight in her and she made me proud again. Best regards to you all, Bill of Georgia N505WP 601XL-3300 --------------------------------------------- Paul Mulwitz 32013 NE Dial Road Camas, WA 98607 --------------------------------------------- --------------------------------- 8:00? 8:25? 8:40? Find a flick in no time with theYahoo! Search movie showtime shortcut. ________________________________ Message 3 _____________________________________ Time: 09:30:49 AM PST US Subject: Re: Zenith-List: Re: Wing flutter! From: japhillipsga@aol.com Gig, slowing down just left me still in the heat collum, I wanted out and away from it as fast as possible and rolling and diving away was the quickest way I could get away from it. Everybody gets to make a choice, but I felt sure that another second or two would have had me flying just a fuselage. Best regards, Bill -----Original Message----- From: wr.giacona@cox.net Sent: Mon, 29 Jan 2007 2:45 PM Subject: Zenith-List: Re: Wing flutter! To increase speed in a situation like this is counter to everything I know, or have ever heard about flying. I'm glad you are OK. DO NOT ARCHIVE -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=91371#91371 ________________________________________________________________________ ________________________________ Message 4 _____________________________________ Time: 09:56:59 AM PST US From: Gary Gower Subject: Re: Zenith-List: Re: 601XL Wing Flutter???? My "best" turbulent ride, was years ago (about 25...) when we were invited to a Xcountry flight competition over the Mojave Desert in a hang glider... In that area, you experience all the "flutter", "G forces" or what ever your fear can imagine, but at the end, just the greatest flight of your life. Never tried Gliders (cabin type) yet, but I think will be a similar experience. Saludos Gary Gower. 701 912S. Do not archive. "T. Graziano" wrote: Hi Bill, Glad everything came out OK. Looks like you ran into some really weird turbulence from the power-plant, giving you an "E" ticket ride. If you were really experiencing wing or control surface flutter, your diving and picking up speed should have exacerbated the problem with the amplitude going divergent very rapidly, until something(s) bends or more likely breaks off. Only saw this once in a film of a dynamic model in a wind tunnel - once flutter started the entire model was gonzo in a second or two. Do you recall experiencing any feed back in the stick/rudder? In 199 hours in my XL, I have had some bumpy rides and the airplane has handled it ok - just glad I always have my seat belt tight. I have also had some GREAT*, almost I would have believed, GOOD*, landings and I agree the airplane is tough. *GREAT Landing - Airplane is still flyable. GOOD Landing - You can walk away from the airplane. Please let us know if you find anything after your in-depth inspection. I kind of suspect you will not find anything amiss, but if you do it would be a good data point for all of us for tailoring our structural inspections. Tony Graziano XL; N493TG -------- Ben, maybe I did not explain well, but it was not control flutter. The aileron did not move independent of the wing. What occurred is the whole wing fluttered with aileron moving with it., best regards, Bill ------------------------- Dear Thread Friends, I went flying this afternoon. Took a fellow with me and just wanted an hour in the clear blue. Conditions were perfect, clear, cool and only a slight wind. The only big thing around much to see nearby is Lake Juliette which has a big coal fired power station in the middle. Three huge steam towers that look like a nuclear power station. We flew around the lake about two miles away at 5000 feet so my pal could get a good look see. On the down wind side we flew into an invisible killer. We were doing above 140 when we flew into it. Instantly the left wing fluttered at a fast pitch, aileron and all and it looked to be moving maybe two inched up and down. I figured a couple seconds would break it off. I didn't have time to look around the passenger to see if the right wing was fluttering, but I suspect it was. I chopped power and did a hard diving wing over to the left and out of it. The flutter sound was great even over my Lightspeed AN system and the whole thing probably last maybe 5 or 6 seconds. I regained control out of the snap dive, maxing above 170 and flew slow and easy back to the field before I tested the controls. Everything felt okay and I could see no wrinkles in the top skin so I landed. Didn't really have much choice. Upon inspection I found no sign of stress, no skin deform, no paint cracked around rivets, nothing. I will take off all inspection panels for a close inspection this weekend and check bolts, controls, etc., but I cannot believe such a prolonged violent movement of the wing did not damage something other than my pride. Two things learned. Don't fly anywhere near a power station. Even at 5000 feet and miles away the invisible heat rises and is most extreme. Maybe intensified in cold weather. The other thing is the XL is very, very tough. Oh, there is a third thing. How could I have been so stupid not to know the first thing !! I am interested though in knowing why the wings fluttered in this thermal? What theory of air dynamics would cause this extreme reaction? Was is just the level of heat and speed the invisible air was streaming past? This was my 90th flight in her and she made me proud again. Best regards to you all, Bill of Georgia N505WP 601XL-3300 --------------------------------- 8:00? 8:25? 8:40? Find a flick in no time with theYahoo! Search movie showtime shortcut. ________________________________ Message 5 _____________________________________ Time: 11:51:25 AM PST US From: "Meltonoso" Subject: FW: Zenith-List: 601XL Wing Flutter Just to feel better about things, you might want to check the torque on your spar bolts, and maybe even pull one and make sure that the tolerance on the bolt is as close as it should be going through the spar box. Alan Melton _____ From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Gary Gower Sent: Tuesday, January 30, 2007 12:13 PM Subject: Re: Zenith-List: 601XL Wing Flutter Hello all, Dont panic! This is simple severe turbulence by a big thermal. Normally a "bumpy" ride is not that way because in this case the heat is concetrated a lot. Like a fly flying over a torch welder :-) Just to make shure, lets remember, in the first signs of turbulence, slow a little the cruise speed, if it get severe, slow to manuver speed and keep alert not to get cought in a high angle attitude, "Ride" the turbulence with the controls as gently as possible... Saludos Gary Gower. Paul Mulwitz wrote: Hi Bill, That was a truly shocking story. I can't help but connect the dots with your flight and the recent events of XL's falling out of the sky. I wonder if you could answer a couple of questions: 1. Which aileron hinges do you have? 2. Do you have the center stick? 3. Did you build from kit or scratch? If you were actually experiencing flutter, then I would have thought slowing down would be the way out. When you increased speed to stop the vibration, did it occur again as you slowed down? I think I'll take up knitting instead of airplane building . .. Paul XL fuselage do not archive At 10:31 PM 1/26/2007, you wrote: Dear Thread Friends, I went flying this afternoon. Took a fellow with me and just wanted an hour in the clear blue. Conditions were perfect, clear, cool and only a slight wind. The only big thing around much to see nearby is Lake Juliette which has a big coal fired power station in the middle. Three huge steam towers that look like a nuclear power station. We flew around the lake about two miles away at 5000 feet so my pal could get a good look see. On the down wind side we flew into an invisible killer. We were doing above 140 when we flew into it. Instantly the left wing fluttered at a fast pitch, aileron and all and it looked to be moving maybe two inched up and down. I figured a couple seconds would break it off. I didn't have time to look around the passenger to see if the right wing was fluttering, but I suspect it was. I chopped power and did a hard diving wing over to the left and out of it. The flutter sound was great even over my Lightspeed AN system and the whole thing probably last maybe 5 or 6 seconds. I regained control out of the snap dive, maxing above 170 and flew slow and easy back to the field before I tested the controls. Everything felt okay and I could see no wrinkles in the top skin so I landed. Didn't really have much choice. Upon inspection I found no sign of stress, no skin deform, no paint cracked around rivets, nothing. I will take off all inspection panels for a close inspection this weekend and check bolts, controls, etc., but I cannot believe such a prolonged violent movement of the wing did not damage something other than my pride. Two things learned. Don't fly anywhere near a power station. Even at 5000 feet and miles away the invisible heat rises and is most extreme. Maybe intensified in cold weather. The other thing is the XL is very, very tough. Oh, there is a third thing. How could I have been so stupid not to know the first thing !! I am interested though in knowing why the wings fluttered in this thermal? What theory of air dynamics would cause this extreme reaction? Was is just the level of heat and speed the invisible air was streaming past? This was my 90th flight in her and she made me proud again. Best regards to you all, Bill of Georgia N505WP 601XL-3300 _____ size=1 width="100%" align=center> 8:00? 8:25? 8:40? Find a flick in no time with theYahoo! Search movie showtime shortcut. ________________________________ Message 6 _____________________________________ Time: 01:48:15 PM PST US From: "Dave Ruddiman" Subject: Re: Zenith-List: Landing Light Kit Assembly Grief I heard that PETA stands for People Eating Tasty Animals. Or something like that. And with that I say, do not archive. ----- Original Message ----- From: Sent: Tuesday, January 30, 2007 7:39 AM Subject: Re: Zenith-List: Landing Light Kit Assembly Grief > > Alternative method: > > Go to dental school then after graduation, do root canals on upper second > molars routinely for let's say..... 30 years or so. Makes assembling the > landing lights look like shooting fish in a barrel (Does anyone actually > shoot fish inside barrels? Why? > What does PETA have to say about that practice? Does anyone care?) > > Sorry...... I had the right to remain silent......... but sadly, I lacked > the discretion, > > Dred > > Please Do Not Archive > Please take good care of those Second Molars > > ---- Brad DeMeo wrote: > >> I experienced a lot of grief trying to hold together the %$@#*! landing >> light assembly while getting it fastened to the channel in the left >> wing........ > > > ________________________________ Message 7 _____________________________________ Time: 02:20:10 PM PST US Subject: Zenith-List: Re: Wing flutter! From: "Gig Giacona" Like I said. I'm glad you came out of it OK. And I hate Monday morning quaterbacking but I don't think at a point where the structure of the aircraft is in question that the best idea is to spead up to within 10 MPH of the VNE of the aircraft. That said have you looked at the attachement points yet? Is there any visible damage? -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=91678#91678 ________________________________ Message 8 _____________________________________ Time: 02:24:12 PM PST US From: Keystone Engineering LLC Subject: Zenith-List: VGs feathers on an 801 Hi I moved the feathers VGs about an inch farther forward. The chord is 57". The front of the VG is at 3" and the back is at 4" behind the leading edge of the wing (along the chord). 3.4" is 6% of the chord. I also installed more Vgs. I continued the 60 mm spacing to the second leading edge slat bracked from the wing tip. The rest of the wing is on a 90 mm spacing. The density altitude was -2500' at take off. I was light about 1600 lbs. Again it climbed like a home sick angle. I was getting 800-900 FPM at 80 mph. The stall speed are the same as they were in my report on Monday. Flaps up 50 Flaps down 45 The flaperons were effective even when the wing is stalled. I may move them to 5% or I may change the VGs on the tail to see if that changes anything. Any suggestions? Bill Wilcox N801BW Valdez, Alaska 280 hrs Slats still off Doing some head scratching, trying to figure out what to do next. Time: 02:01:08 PM PST US From: "JG" Subject: Re: Zenith-List: Re: VGs feathers on an 801 Gday Bill, Well, that's interesting...... Yeh, one of the first things you do notice from removing slats is the increase in climb - all that power (about 23% measured on the Savannah) that was used to overcome the drag is now available for climb. A bit disappointed in the stall characteristics tho - our 701's and Savannahs just get back to a high descent mush, much like with the slats. What's the position of your Feathers now?? It sounds like they could be better even farther forward - I'd try them at 7%. Wishing you some good weather for further experimenting. Here we have lots of 37*C (99*F) weather to spare, but even if we could send some of it to you, I guess it would be a mess on top of 20 ft of snow....... JG ----- Original Message ----- From: "Keystone Engineering LLC" Sent: Monday, January 29, 2007 4:54 PM Subject: Zenith-List: Re: VGs feathers on an 801 > > > Hi > > I got about 30 minutes of weather good enough to fly this afternoon. The > leading edge slats are off and the feather VGs are on. It seemed to want > to climb like a home sick angel. I was light (1600 lbs), 30 gallons of > fuel and 230 pounds of me with nothing else. I saw 900 FPM at 80 MPH. > Density altitude on the ground was -1500'. The plane flew good I did not > notice any CG issues. > > Before After > Cruise 103 MPH 111 MPH both > adjusted to 4500' standard temp at 85% power 10.5 GPH leaned to 150 ROP > No flaps stall None Buffet at 58, > stall 50 indicated and GPS > Full flaps stall None I assumed 38 45 indicated 49 GPS > (only done once) > Approach speed 50 58 > Take off run Very short Much longer > 250' 350' > Landing distance: the breaking action was poor so I did not measure. > > I need to fly more in this configuration. The fog moved in and I was > going to bust FARs so I landed. > > It is weird flying a plane that will actually stall! I think it may be a > better plane to teach the kids to fly. They would learn what stalls feels > like. The flaperons are effective even in the stall. > > The VG spacing for the outboard 3' is at 60 MM and the rest are at 90 mm > spacing. I may change the spacing to 60 MM for the length of the > "aileron". This hopefully will still give aileron control and inner part > of wing stalling first but still lower speeds. > > Bill Wilcox > N801BW > Valdez, Alaska > 280 hrs > Waiting for a flying day. Going to replace the VGs on the tail with more, > smaller VGs with less angle. > > > ----- Original Message ----- > From: "Bill Wilcox" > To: > Cc: ; > Sent: Sunday, January 28, 2007 11:31 AM > Subject: VGs feathers > > >> JG >> >> I got the feathers you sent. Thank you!! >> >> I took the old VGs off and put the feathers on last night. All I need >> now is a nice day. >> >> We have been having snow storm after snow storm lately. So far this >> winter we have received 250" of snow. Thus is life in the snow capital >> of the world. >> >> Flight test results soon. >> >> Bill Wilcox >> N801BW >> Valdez, Alaska >> 280 hrs >> Waiting for a nice day >> > > > ________________________________ Message 9 _____________________________________ Time: 02:40:21 PM PST US From: "Dave Ruddiman" Subject: Re: Zenith-List: VGs feathers on an 801 Bill, I've kind of been keeping up on the slat issue. Does anyone use VG's with slats? Does the slat change the airflow over the wing where the VG's have effect? These are just questions I don't really know anything about. I plan on using my slats anyway, but I'm curious about this issue. Thanks, Dave in Salem - almost done with the wings. ----- Original Message ----- From: Keystone Engineering LLC To: zenith-list@matronics.com Sent: Tuesday, January 30, 2007 2:23 PM Subject: Zenith-List: VGs feathers on an 801 Hi I moved the feathers VGs about an inch farther forward. The chord is 57". The front of the VG is at 3" and the back is at 4" behind the leading edge of the wing (along the chord). 3.4" is 6% of the chord. I also installed more Vgs. I continued the 60 mm spacing to the second leading edge slat bracked from the wing tip. The rest of the wing is on a 90 mm spacing. The density altitude was -2500' at take off. I was light about 1600 lbs. Again it climbed like a home sick angle. I was getting 800-900 FPM at 80 mph. The stall speed are the same as they were in my report on Monday. Flaps up 50 Flaps down 45 The flaperons were effective even when the wing is stalled. I may move them to 5% or I may change the VGs on the tail to see if that changes anything. Any suggestions? Bill Wilcox N801BW Valdez, Alaska 280 hrs Slats still off Doing some head scratching, trying to figure out what to do next. Time: 02:01:08 PM PST US From: "JG" Subject: Re: Zenith-List: Re: VGs feathers on an 801 Gday Bill, Well, that's interesting...... Yeh, one of the first things you do notice from removing slats is the increase in climb - all that power (about 23% measured on the Savannah) that was used to overcome the drag is now available for climb. A bit disappointed in the stall characteristics tho - our 701's and Savannahs just get back to a high descent mush, much like with the slats. What's the position of your Feathers now?? It sounds like they could be better even farther forward - I'd try them at 7%. Wishing you some good weather for further experimenting. Here we have lots of 37*C (99*F) weather to spare, but even if we could send some of it to you, I guess it would be a mess on top of 20 ft of snow....... JG ----- Original Message ----- From: "Keystone Engineering LLC" Sent: Monday, January 29, 2007 4:54 PM Subject: Zenith-List: Re: VGs feathers on an 801 > > > Hi > > I got about 30 minutes of weather good enough to fly this afternoon. The > leading edge slats are off and the feather VGs are on. It seemed to want > to climb like a home sick angel. I was light (1600 lbs), 30 gallons of > fuel and 230 pounds of me with nothing else. I saw 900 FPM at 80 MPH. > Density altitude on the ground was -1500'. The plane flew good I did not > notice any CG issues. > > Before After > Cruise 103 MPH 111 MPH both > adjusted to 4500' standard temp at 85% power 10.5 GPH leaned to 150 ROP > No flaps stall None Buffet at 58, > stall 50 indicated and GPS > Full flaps stall None I assumed 38 45 indicated 49 GPS > (only done once) > Approach speed 50 58 > Take off run Very short Much longer > 250' 350' > Landing distance: the breaking action was poor so I did not measure. > > I need to fly more in this configuration. The fog moved in and I was > going to bust FARs so I landed. > > It is weird flying a plane that will actually stall! I think it may be a > better plane to teach the kids to fly. They would learn what stalls feels > like. The flaperons are effective even in the stall. > > The VG spacing for the outboard 3' is at 60 MM and the rest are at 90 mm > spacing. I may change the spacing to 60 MM for the length of the > "aileron". This hopefully will still give aileron control and inner part > of wing stalling first but still lower speeds. > > Bill Wilcox > N801BW > Valdez, Alaska > 280 hrs > Waiting for a flying day. Going to replace the VGs on the tail with more, > smaller VGs with less angle. > > > ----- Original Message ----- > From: "Bill Wilcox" > To: > Cc: ; > Sent: Sunday, January 28, 2007 11:31 AM > Subject: VGs feathers > > >> JG >> >> I got the feathers you sent. Thank you!! >> >> I took the old VGs off and put the feathers on last night. All I need >> now is a nice day. >> >> We have been having snow storm after snow storm lately. So far this >> winter we have received 250" of snow. Thus is life in the snow capital >> of the world. >> >> Flight test results soon. >> >> Bill Wilcox >> N801BW >> Valdez, Alaska >> 280 hrs >> Waiting for a nice day >> > > > ________________________________ Message 10 ____________________________________ Time: 02:50:26 PM PST US From: Subject: Zenith-List: Wing Flutter Bill: I don't claim to be an expert on the subject but I do have 22 years of military flying with much of it as a flight engineer on medium transports. I think what you experienced was severe vortexing over the wing tips due to the hot air below the wing caused by the power plant opposed to the relatively cool air above. The extreme vortexing phenomena produced a "hammering effect" on the top of the wing causing it to flutter. I've experienced similar situations during descent and final approach during extremely hot days while flying with the Corps of Engineers in Saudi Arabia. James D. Webber GS-11 Senior Training Specialist Department of Attack Helicopter Training jim.webber@eustis.army.mil ________________________________ Message 11 ____________________________________ Time: 03:01:35 PM PST US From: "JG" Subject: Re: Zenith-List: VGs feathers on an 801 Dave, Yeh, I tried the VGs with slats. They make no difference in that situation because the slats already give the accelerated airflow that stays attached at high AoA. The slats do that job well, it's just that they bring a very high drag that stays at all speeds including climb - note Bill's observation about "climbing like an angel" - it's the reduction in drag by removing the slats that gives the improvement. JG ----- Original Message ----- From: Dave Ruddiman To: zenith-list@matronics.com Sent: Wednesday, January 31, 2007 9:39 AM Subject: Re: Zenith-List: VGs feathers on an 801 Bill, I've kind of been keeping up on the slat issue. Does anyone use VG's with slats? Does the slat change the airflow over the wing where the VG's have effect? These are just questions I don't really know anything about. I plan on using my slats anyway, but I'm curious about this issue. Thanks, Dave in Salem - almost done with the wings. ----- Original Message ----- From: Keystone Engineering LLC To: zenith-list@matronics.com Sent: Tuesday, January 30, 2007 2:23 PM Subject: Zenith-List: VGs feathers on an 801 Hi I moved the feathers VGs about an inch farther forward. The chord is 57". The front of the VG is at 3" and the back is at 4" behind the leading edge of the wing (along the chord). 3.4" is 6% of the chord. I also installed more Vgs. I continued the 60 mm spacing to the second leading edge slat bracked from the wing tip. The rest of the wing is on a 90 mm spacing. The density altitude was -2500' at take off. I was light about 1600 lbs. Again it climbed like a home sick angle. I was getting 800-900 FPM at 80 mph. The stall speed are the same as they were in my report on Monday. Flaps up 50 Flaps down 45 The flaperons were effective even when the wing is stalled. I may move them to 5% or I may change the VGs on the tail to see if that changes anything. Any suggestions? Bill Wilcox N801BW Valdez, Alaska 280 hrs Slats still off Doing some head scratching, trying to figure out what to do next. Time: 02:01:08 PM PST US From: "JG" Subject: Re: Zenith-List: Re: VGs feathers on an 801 Gday Bill, Well, that's interesting...... Yeh, one of the first things you do notice from removing slats is the increase in climb - all that power (about 23% measured on the Savannah) that was used to overcome the drag is now available for climb. A bit disappointed in the stall characteristics tho - our 701's and Savannahs just get back to a high descent mush, much like with the slats. What's the position of your Feathers now?? It sounds like they could be better even farther forward - I'd try them at 7%. Wishing you some good weather for further experimenting. Here we have lots of 37*C (99*F) weather to spare, but even if we could send some of it to you, I guess it would be a mess on top of 20 ft of snow....... JG ----- Original Message ----- From: "Keystone Engineering LLC" Sent: Monday, January 29, 2007 4:54 PM Subject: Zenith-List: Re: VGs feathers on an 801 > > > Hi > > I got about 30 minutes of weather good enough to fly this afternoon. The > leading edge slats are off and the feather VGs are on. It seemed to want > to climb like a home sick angel. I was light (1600 lbs), 30 gallons of > fuel and 230 pounds of me with nothing else. I saw 900 FPM at 80 MPH. > Density altitude on the ground was -1500'. The plane flew good I did not > notice any CG issues. > > Before After > Cruise 103 MPH 111 MPH both > adjusted to 4500' standard temp at 85% power 10.5 GPH leaned to 150 ROP > No flaps stall None Buffet at 58, > stall 50 indicated and GPS > Full flaps stall None I assumed 38 45 indicated 49 GPS > (only done once) > Approach speed 50 58 > Take off run Very short Much longer > 250' 350' > Landing distance: the breaking action was poor so I did not measure. > > I need to fly more in this configuration. The fog moved in and I was > going to bust FARs so I landed. > > It is weird flying a plane that will actually stall! I think it may be a > better plane to teach the kids to fly. They would learn what stalls feels > like. The flaperons are effective even in the stall. > > The VG spacing for the outboard 3' is at 60 MM and the rest are at 90 mm > spacing. I may change the spacing to 60 MM for the length of the > "aileron". This hopefully will still give aileron control and inner part > of wing stalling first but still lower speeds. > > Bill Wilcox > N801BW > Valdez, Alaska > 280 hrs > Waiting for a flying day. Going to replace the VGs on the tail with more, > smaller VGs with less angle. > > > ----- Original Message ----- > From: "Bill Wilcox" > To: > Cc: ; > Sent: Sunday, January 28, 2007 11:31 AM > Subject: VGs feathers > > >> JG >> >> I got the feathers you sent. Thank you!! >> >> I took the old VGs off and put the feathers on last night. All I need >> now is a nice day. >> >> We have been having snow storm after snow storm lately. So far this >> winter we have received 250" of snow. Thus is life in the snow capital >> of the world. >> >> Flight test results soon. >> >> Bill Wilcox >> N801BW >> Valdez, Alaska >> 280 hrs >> Waiting for a nice day >> > > > ________________________________ Message 12 ____________________________________ Time: 03:15:25 PM PST US From: "Dave Ruddiman" Subject: Re: Zenith-List: VGs feathers on an 801 THANKS. THAT CLEARS THINGS UP. ----- Original Message ----- From: JG To: zenith-list@matronics.com Sent: Tuesday, January 30, 2007 3:00 PM Subject: Re: Zenith-List: VGs feathers on an 801 Dave, Yeh, I tried the VGs with slats. They make no difference in that situation because the slats already give the accelerated airflow that stays attached at high AoA. The slats do that job well, it's just that they bring a very high drag that stays at all speeds including climb - note Bill's observation about "climbing like an angel" - it's the reduction in drag by removing the slats that gives the improvement. JG ----- Original Message ----- From: Dave Ruddiman To: zenith-list@matronics.com Sent: Wednesday, January 31, 2007 9:39 AM Subject: Re: Zenith-List: VGs feathers on an 801 Bill, I've kind of been keeping up on the slat issue. Does anyone use VG's with slats? Does the slat change the airflow over the wing where the VG's have effect? These are just questions I don't really know anything about. I plan on using my slats anyway, but I'm curious about this issue. Thanks, Dave in Salem - almost done with the wings. ----- Original Message ----- From: Keystone Engineering LLC To: zenith-list@matronics.com Sent: Tuesday, January 30, 2007 2:23 PM Subject: Zenith-List: VGs feathers on an 801 Hi I moved the feathers VGs about an inch farther forward. The chord is 57". The front of the VG is at 3" and the back is at 4" behind the leading edge of the wing (along the chord). 3.4" is 6% of the chord. I also installed more Vgs. I continued the 60 mm spacing to the second leading edge slat bracked from the wing tip. The rest of the wing is on a 90 mm spacing. The density altitude was -2500' at take off. I was light about 1600 lbs. Again it climbed like a home sick angle. I was getting 800-900 FPM at 80 mph. The stall speed are the same as they were in my report on Monday. Flaps up 50 Flaps down 45 The flaperons were effective even when the wing is stalled. I may move them to 5% or I may change the VGs on the tail to see if that changes anything. Any suggestions? Bill Wilcox N801BW Valdez, Alaska 280 hrs Slats still off Doing some head scratching, trying to figure out what to do next. Time: 02:01:08 PM PST US From: "JG" Subject: Re: Zenith-List: Re: VGs feathers on an 801 Gday Bill, Well, that's interesting...... Yeh, one of the first things you do notice from removing slats is the increase in climb - all that power (about 23% measured on the Savannah) that was used to overcome the drag is now available for climb. A bit disappointed in the stall characteristics tho - our 701's and Savannahs just get back to a high descent mush, much like with the slats. What's the position of your Feathers now?? It sounds like they could be better even farther forward - I'd try them at 7%. Wishing you some good weather for further experimenting. Here we have lots of 37*C (99*F) weather to spare, but even if we could send some of it to you, I guess it would be a mess on top of 20 ft of snow....... JG ----- Original Message ----- From: "Keystone Engineering LLC" Sent: Monday, January 29, 2007 4:54 PM Subject: Zenith-List: Re: VGs feathers on an 801 > > > Hi > > I got about 30 minutes of weather good enough to fly this afternoon. The > leading edge slats are off and the feather VGs are on. It seemed to want > to climb like a home sick angel. I was light (1600 lbs), 30 gallons of > fuel and 230 pounds of me with nothing else. I saw 900 FPM at 80 MPH. > Density altitude on the ground was -1500'. The plane flew good I did not > notice any CG issues. > > Before After > Cruise 103 MPH 111 MPH both > adjusted to 4500' standard temp at 85% power 10.5 GPH leaned to 150 ROP > No flaps stall None Buffet at 58, > stall 50 indicated and GPS > Full flaps stall None I assumed 38 45 indicated 49 GPS > (only done once) > Approach speed 50 58 > Take off run Very short Much longer > 250' 350' > Landing distance: the breaking action was poor so I did not measure. > > I need to fly more in this configuration. The fog moved in and I was > going to bust FARs so I landed. > > It is weird flying a plane that will actually stall! I think it may be a > better plane to teach the kids to fly. They would learn what stalls feels > like. The flaperons are effective even in the stall. > > The VG spacing for the outboard 3' is at 60 MM and the rest are at 90 mm > spacing. I may change the spacing to 60 MM for the length of the > "aileron". This hopefully will still give aileron control and inner part > of wing stalling first but still lower speeds. > > Bill Wilcox > N801BW > Valdez, Alaska > 280 hrs > Waiting for a flying day. Going to replace the VGs on the tail with more, > smaller VGs with less angle. > > > ----- Original Message ----- > From: "Bill Wilcox" > To: > Cc: ; > Sent: Sunday, January 28, 2007 11:31 AM > Subject: VGs feathers > > >> JG >> >> I got the feathers you sent. Thank you!! >> >> I took the old VGs off and put the feathers on last night. All I need >> now is a nice day. >> >> We have been having snow storm after snow storm lately. So far this >> winter we have received 250" of snow. Thus is life in the snow capital >> of the world. >> >> Flight test results soon. >> >> Bill Wilcox >> N801BW >> Valdez, Alaska >> 280 hrs >> Waiting for a nice day >> > > > href="http://www.matronics.com/Navigator?Zenith-List">http://www.matron href="http://forums.matronics.com">http://forums.matronics.com ________________________________ Message 13 ____________________________________ Time: 04:28:53 PM PST US From: Jennifer Moorhouse Subject: Zenith-List: Re: airplanes to compare to XL Wow. I'm reading through everyone's responses to my question several times, and jotting notes. When I get ink for the printer, I might print them out. Thank you for the great information. I'm in the middle TN area. Rich Simmons has told me of a few other XLs in the state. I hope I can get to fly one sometime. I was originally planning on having my third wheel on my tail end, but recently decided I don't want all that extra work load every time I go out to play, so it's tri gear for me. I let the flight school that owns the Katana I flew over the weekend know of it pulling so hard to the right on the ground and have learned it has had a dragging right brake before. Now I can't remember everything I was going to type. I do want to let you all know that because of your responses, I was so encouraged yesterday, that I went and cut the channel out for my elevator trim tab. Now to find my darn cleco pliers . . . Do not archive --------------------------------- Never miss an email again! Yahoo! Toolbar alerts you the instant new Mail arrives. Check it out. ________________________________ Message 14 ____________________________________ Time: 04:33:27 PM PST US From: Juan Vega Subject: Re: Zenith-List: Re: Spin 601xl any experience, caveates, unusual recovery techn why would they spend the capital to modify the AMD elevator and not the kit built, what I understand is that AMD recieves Quick built kits just like the rest of us, as well as the famed taller landing gear. Do they in fact have taller landing gear? JUan -----Original Message----- >From: David X >Sent: Jan 29, 2007 11:38 PM >To: zenith-list@matronics.com >Subject: Zenith-List: Re: Spin 601xl any experience, caveates, unusual recovery techn > > > >amyvega2005(at)earthlink. wrote: >> how do you get more command of the AMD planes versus the Kit? > > >AMD changed the geometry on the elevator control to give it a little more travel; thus more command under unusual attitudes during certain extreme rearward CG scenarios or when exceeding maximum gross. Keep in mind that they are building so-called "certified" aircraft for the SLSA market that come with manufacture's liability. Zenith probably has zero liability with the kit planes. Czech Aircraft Works also tested their 601XL well past the rear CG limits and also made modifications to the design. > >I don't know if the AMD modifications made it back into the kit designs, but the CZAW modifications definately didn't (other than prehaps the motor mount for the 912S). Someone would have to compare old drawings to more recent ones to see what exactly has changed if anything. > >There is so much margin for safety in the so-called limits that you have very little to worry about so long as you stay within the limits and keep your pilot skills current. Get some training in a spin-certified plane so that you get experience in basic recovery technique rather than just relying on theory. Spin training isn't required for a pilot's license anymore, but you should get the training at each bi-annual anyway (in my opinion). > >The 601 - like most small planes - will recover from a spin or unusual attitude without difficulty if the recovery is executed properly. > >-------- >Zodiac 601 XL - CZAW Built - Rotax 912S >DO NOT ARCHIVE > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=91504#91504 > > ________________________________ Message 15 ____________________________________ Time: 04:38:34 PM PST US From: "John Fulp" Subject: RE: Zenith-List: Wing Flutter You were in the wrong place/wrong time...the warm/cold air set-up a perfect (bad) wing frequency harmonic...instead of diving you should have pulled UP...slow...get your bearings...diving to 170MPH?? You should be ???? Glad your OK John -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of djdormer@cox.net Sent: Tuesday, January 30, 2007 5:50 PM Subject: Zenith-List: Wing Flutter Bill: I don't claim to be an expert on the subject but I do have 22 years of military flying with much of it as a flight engineer on medium transports. I think what you experienced was severe vortexing over the wing tips due to the hot air below the wing caused by the power plant opposed to the relatively cool air above. The extreme vortexing phenomena produced a "hammering effect" on the top of the wing causing it to flutter. I've experienced similar situations during descent and final approach during extremely hot days while flying with the Corps of Engineers in Saudi Arabia. James D. Webber GS-11 Senior Training Specialist Department of Attack Helicopter Training jim.webber@eustis.army.mil ________________________________ Message 16 ____________________________________ Time: 04:57:14 PM PST US From: Keystone Engineering LLC Subject: Zenith-List: VGs feathers on an 801 Dave My understanding is "stacking" high lift devices on top of each other does not add significantly to the performance. I plan on putting the slats back on over the VGs. I'm planning on having the take off and landing distances measured in both configurations at the Valdez May Day Fly-in. Bill Bill, I've kind of been keeping up on the slat issue. Does anyone use VG's with slats? Does the slat change the airflow over the wing where the VG's have effect? These are just questions I don't really know anything about. I plan on using my slats anyway, but I'm curious about this issue. Thanks, Dave in Salem - almost done with the wings. ----- Original Message ----- From: Keystone Engineering LLC To: zenith-list@matronics.com Sent: Tuesday, January 30, 2007 2:23 PM Subject: VGs feathers on an 801 Hi I moved the feathers VGs about an inch farther forward. The chord is 57". The front of the VG is at 3" and the back is at 4" behind the leading edge of the wing (along the chord). 3.4" is 6% of the chord. I also installed more Vgs. I continued the 60 mm spacing to the second leading edge slat bracked from the wing tip. The rest of the wing is on a 90 mm spacing. The density altitude was -2500' at take off. I was light about 1600 lbs. Again it climbed like a home sick angle. I was getting 800-900 FPM at 80 mph. The stall speed are the same as they were in my report on Monday. Flaps up 50 Flaps down 45 The flaperons were effective even when the wing is stalled. I may move them to 5% or I may change the VGs on the tail to see if that changes anything. Any suggestions? Bill Wilcox N801BW Valdez, Alaska 280 hrs Slats still off Doing some head scratching, trying to figure out what to do next. T ________________________________ Message 17 ____________________________________ Time: 06:25:32 PM PST US From: Subject: Zenith-List: vg feathers on an 801 Bill, I don't know the 801 wing but my experience on a Legal Eagle and a 701 leads me to suggest that you try 8 %. That works great on both of those wings. It's possible that at 6% the vortex is "flattening out" against the remainder of the leading edge with consequent loss of effectiveness. I tried vgs under the HS of my 701. I lost 2.5 mph and about 10-12% ROC. The only benefit that I could see was a lighter pitch feel but no increased effectiveness. I removed them in favor of the increased performance over a lighter elevator. FWIW Joe ________________________________ Message 18 ____________________________________ Time: 07:32:19 PM PST US From: "Dave Ruddiman" Subject: Re: Zenith-List: VGs feathers on an 801 Bill, Be sure and post what your results are for the take off and landings. I'm more interested in those numbers than anything else. I think my plane will be configured similar to yours when I'm finished. I have a picture of you and your plane on the wall in the shop. It's nice to see what the finished product will look like. Keeps me motivated. Dave ----- Original Message ----- From: Keystone Engineering LLC To: zenith-list@matronics.com Sent: Tuesday, January 30, 2007 4:56 PM Subject: Zenith-List: VGs feathers on an 801 Dave My understanding is "stacking" high lift devices on top of each other does not add significantly to the performance. I plan on putting the slats back on over the VGs. I'm planning on having the take off and landing distances measured in both configurations at the Valdez May Day Fly-in. Bill Bill, I've kind of been keeping up on the slat issue. Does anyone use VG's with slats? Does the slat change the airflow over the wing where the VG's have effect? These are just questions I don't really know anything about. I plan on using my slats anyway, but I'm curious about this issue. Thanks, Dave in Salem - almost done with the wings. ----- Original Message ----- From: Keystone Engineering LLC To: zenith-list@matronics.com Sent: Tuesday, January 30, 2007 2:23 PM Subject: VGs feathers on an 801 Hi I moved the feathers VGs about an inch farther forward. The chord is 57". The front of the VG is at 3" and the back is at 4" behind the leading edge of the wing (along the chord). 3.4" is 6% of the chord. I also installed more Vgs. I continued the 60 mm spacing to the second leading edge slat bracked from the wing tip. The rest of the wing is on a 90 mm spacing. The density altitude was -2500' at take off. I was light about 1600 lbs. Again it climbed like a home sick angle. I was getting 800-900 FPM at 80 mph. The stall speed are the same as they were in my report on Monday. Flaps up 50 Flaps down 45 The flaperons were effective even when the wing is stalled. I may move them to 5% or I may change the VGs on the tail to see if that changes anything. Any suggestions? Bill Wilcox N801BW Valdez, Alaska 280 hrs Slats still off Doing some head scratching, trying to figure out what to do next. T ________________________________ Message 19 ____________________________________ Time: 09:32:04 PM PST US Subject: Zenith-List: Re: Spin 601xl any experience, caveates, unusual recovery techn From: "David X" I only know what they did for the prototype that they used for testing and certification. -------- Zodiac 601 XL - CZAW Built - Rotax 912S DO NOT ARCHIVE Read this topic online here: http://forums.matronics.com/viewtopic.php?p=91763#91763 ________________________________ Message 20 ____________________________________ Time: 09:37:27 PM PST US Subject: Zenith-List: Re: 601XL Wing Flutter From: "David X" Still curious what type of aeileron hinges you have. -------- Zodiac 601 XL - CZAW Built - Rotax 912S DO NOT ARCHIVE Read this topic online here: http://forums.matronics.com/viewtopic.php?p=91764#91764 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith-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/zenith-list Browse Digests http://www.matronics.com/digest/zenith-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.