Kennedy Composites Supra - Verdict?

[ClayH]

There have been some Kenndy Composite Supras lost recently due to structural failure on F3J two man tow launches. I believe these were the full carbon versions flown by very prominent pilots. I have just started building my glass version which will be used for TD only. My question is, is the glass Supra holding up well for those that are flying them in TD only. I know they fly nice, just wondering if I should be concerned about the longevity of the plane under normal use. I haven't heard/read anything from Kennedy regarding the exlposions occuring to our USA F3J team members' Supras. What's the verdict?

Clay

[OVSS Boss]

A number fly here in the midwest and are doing fine, saw one maidened Sunday also.

Marc

[mnluz]

There are two flying in Brazil. Flew mine on hand tow and wind two weeks ago and it was fine..... bending a lot so I don't recommend the glass version for hand tow.
Mine is a glass version and first generation. Had to add a nut on the v mount and change the wing bolts for longer bolts.

Improvements have been made, as expected from a great manufacturer. You need to know what version or improvements you have and fix it.

I have glass #59 and glass #110. 110 came in with the vmount fixed and longer wing bolts.

Somewhere after the # 110 I heard that the new ones got a stiffer stab and fuselage reinforcement on the blind nut system that holds the wing.
The really new, new ones will come with new strong spar system more like the European construction. With the new spar I guess even the glass version will do alright on hand tow.

I'm getting a new center section for the WC, just because of hand tow. On most of the days, TD, the first generation glass supra will work for me and for most pilots.

It takes a lot of finesse, training and tuning to push a plane so hard to have a failure. I wish I could launch that hard and that high :D

Just my opinion... after all we have only 2 down here. You have way more experience with the plane in the US.

It is the best plane I ever had.... made me retire my superior in 2 secs. I'm a HLG fan so the supra matches my style very well and I have a blast every time a fly it. It is a keeper..... for the next 3 year I hope.

All the Best,
Marlon
* leaving in 7 days for the WC
** the plane that failed in Denver was exactly like mine.... same color and regular glass version "first generation".

[eye_rc_soar]

I lost carbon supra #48 on winch launch due to structural failure of the fuselage wing saddle wing pylon attachment. The wing saddle with wing bolts and blind nuts separated from the fuselage wing pylon. Those of you with old style fuselages are encouraged to drill out the current blind nuts and make a new blind nut retainer that is captive below the wing pylon. This fix has been discussed before, but I didn't heed the warning.

Carbon Supra #148 has two significant improvements. First the fuselage wing saddle blind nut system is much improved and heavily reinforced. There are actually two aluminum rings that capture the ballast tube and are the base of the wing attachment blind nuts. Second, I've got the new carbon wrapped spar in the center section. Don't know anything about the stab improvements, I don't use them. I use a much lighter set of bagged stabs from Phil Barnes.

Don

[ClayH]

Don,

Was your 1st Supra undamaged prior to losing the wing saddle? If that is the case, I would expect Kennedy to offer to replace any of the pods that had the original wing bolt design. I have glass version #30 and will only be doing TD from the winch,but I guess I'll do the re-inforcement just to be safe.

What was the issue with the V mount?

Clay

[little flyer]

...

[cody303]

I just got back from hand towing mine and launching it on an F3B winch, it flexes but does fine. Joe Wurts is the only one that I know of that snapped the spar and that was in strong wind. The other failures are from flutter, one way to fix the flutter is to put vertical grain balsa ribs on each side of the servo bays. Other than that it is a good flying plane and should be fine for TD.

Little Cody
* leaving in 6 days for the WC

[mnluz]

See you there little Cody, I will have a glass supra for early and late in the afternoon flights and a second one with a carbon center section and new spar for strong wind.

Looks like the Brazilian team will get there one day after the USA team. we are leaving in 7 days.

* I may take my supra for a little slope soaring after the WC. See what that thin airfoil does. :D

[eye_rc_soar]

Don,

Was your 1st Supra undamaged prior to losing the wing saddle? ...



Supra #48 had no visible damage before the wing saddle separated from the wing pylon. The plane had its share of competive spot landings, with a couple admitted dorks. But non of the landings were out of the ordinary for a competitive TD plane. The plane was commonly launched on normal Ford long shaft winches and my F3B winch with mono. Yes, the wing would flex and I was always trying to maximize launch settings. When it finally failed I was really straining the winch on a shorter than normal line.


What was the issue with the V mount? ...


The threads can strip in the v-mount platform. The simple solution is to install a blind nut. I have heard of people loosing horizontal stabs in flight due to this issue. I don't use the v-mount platform that comes with the kit. I adapt a Bud Elder platform to Vlad's "V structure" since I am using a bagged horizontal stab.

Any design evolves with time... This is a good ship whether you fly the molded version or the bagged version.

don

[cody303]

I will see you there too Marlon. The Supra should be a lot of fun on a slope.

Good luck,
Little Cody

[kevin6Q]

What's a 2 man hand tow and why does it strike fear into pilots more then the winch?

[Tuomo]

What's a 2 man hand tow and why does it strike fear into pilots more then the winch?

Here you go!

http://www.f3x.no/f3j/2004/pictures12/team_aussie_throw.jpg

Not that bad really. With a F3B winch and mono line you gets little higher (150m to turn around).

http://www.workflow.as/jogrini/diary/960supra/supra_throw.jpg

In this pic from Jo Grini web site Supra has quite radical wing flex despite the light conditions. What does it look like at the moment of release :eek:

[Goinav8n]

I was there in Denver when Joes Supra folded the wing. He was on a winch and the wind was blowing about 15 knots. In the bottom of the zoom just before the pull up it let go. Im not sure but I think his plane had some Damage before this happened. I mean it had been repaired on the fuse.

So Tom K wanted to see if his wing was gonna be strong enough. His wing was repaired by him. So there may have been some dought in the strenght of the wing. I helped Phil Barnes pull Toms plane. It held up just fine. It was tested and held up. Phil and I are about the same size so we were not holding back on the launch. Frank Burnowski and Phil pulled it during the contest Sat. and it held up.

Its a good plane. I did see some stabs come off. It appeared only 3 threads were holding the stab on. The blind nut fixed this problem and I believe it has been fixed by Vladimir. Rumor has it the newer version will have glass in the vertical shear web to further increase the strenght of the spar.

All good info and cont. devlopment of a good plane

Jeff

[markdrela]

In this pic from Jo Grini web site Supra has quite radical wing flex despite the light conditions.
Most of that "flex" is just the natural dihedral. And besides, some flex is OK as long as the wing doesn't break. I regularly flex my own Supra at least 12" (30cm) at each tip on a hard launch.

[Tom Gressman]

I just got back from hand towing mine and launching it on an F3B winch, it flexes but does fine. Joe Wurts is the only one that I know of that snapped the spar and that was in strong wind. The other failures are from flutter, one way to fix the flutter is to put vertical grain balsa ribs on each side of the servo bays. Other than that it is a good flying plane and should be fine for TD.

Little Cody
* leaving in 6 days for the WC
Good luck! Tom

[ClayH]

Don writes "Those of you with old style fuselages are encouraged to drill out the current blind nuts and make a new blind nut retainer that is captive below the wing pylon. This fix has been discussed before, but I didn't heed the warning."

Don,
I can't find where this fix is discussed. Do you remember the thread? Not a lot of room to work with the very small hole provided in the wing saddle, not to mention that the ballast tube goes right under the bolts.

Clay

[spatial]

The fix was originally discussed on RCSE, look here for pics and a summary of suggestions:
http://www.hilaunch.com/Supra.htm

[crobinett]

Question -what is the suggested repair for the elevator using a blind nut?

Little concerned about that small piece of aluminum for either loss or stripping.

Chuck

[Kiesling]

Hi Chuck,

I did not use a blind nut to fix my v-mount. I used plain hex nut. I pulled out the stud that is in the V-mount and drilled out the hole to accept a 6-32 bolt. Right under the V-mount platform I carefully made a slot in the top of the control horn so I could slide in the hex nut. I used some thickened epoxy to hold the nut in place.

Tom

[crobinett]

Tom,

Thanks for the input. I was having a hard time seeing how a blind nut could be used without significantly cutting the V-mount platform.

Chuck

[markdrela]

PS
Here's a photo of my Supra on a moderate tow: http://www.lisf.org/Pictures/234_3475.jpg
A few times I've had it flex maybe 50% more than that with no problem.

The point is that even alarming-looking wing flex does not imply impending structural failure, as long as the spar is properly designed and without structural flaws.

[mnluz]

Hi Chuck,

I did not use a blind nut to fix my v-mount. I used plain hex nut. I pulled out the stud that is in the V-mount and drilled out the hole to accept a 6-32 bolt. Right under the V-mount platform I carefully made a slot in the top of the control horn so I could slide in the hex nut. I used some thickened epoxy to hold the nut in place.

Tom

Did the same on mine, # 59. Quite easy and just a few grams;
Added a few carbon strips over the nut and you can´t even tell that the hex nut is there.

[mnluz]

The fix was originally discussed on RCSE, look here for pics and a summary of suggestions:
http://www.hilaunch.com/Supra.htm

I just added more epoxy to the existing epoxy aound the blind nut, trying to make contact to every single place on the fuse that I could.
There are more than a hundred supras flying perfectly....I did not want to go to a fuse surgery so I just did this half an hour inprovement for " peace of mind".

[mnluz]

PS
Here's a photo of my Supra on a moderate tow: http://www.lisf.org/Pictures/234_3475.jpg
A few times I've had it flex maybe 50% more than that with no problem.

The point is that even alarming-looking wing flex does not imply impending structural failure, as long as the spar is properly designed and without structural flaws.

Amazing ! that is how mine looked on a modarate day and hand tow. Nice pic.
By the way.... big thanks from the brazilian pilots for putting together such a nice design !!!

I fly from scale to HLG, the xp4 was by far my most enjoyable plane to fly. With the supra I have the same amount of "joy" while flying f3j.

All the best,
Marlon

[Joe W]

PS
Here's a photo of my Supra on a moderate tow: http://www.lisf.org/Pictures/234_3475.jpg
A few times I've had it flex maybe 50% more than that with no problem.

The point is that even alarming-looking wing flex does not imply impending structural failure, as long as the spar is properly designed and without structural flaws.

Hmmm... This isn't very much flex for a Supra... Tom and I have achieved at least twice as much flexure during launch as this. Of course, I finally over-achieved on my original Supra. I now have #149 in the air. I've only winch launched it, haven't hand towed it yet. Has a bunch of improvements compared to my old #34. We will see how it holds up next week!

Joe

PS Also have a new Icon that is the same weight as #149. Interesting to switch back and forth between them. Some things are similar, some are very different.

[Steve Lucke]

I'll have to be careful. I have number 32. :)

[Ben Diss]

Joe- Yes and ... go on. What's different?

[Tom Gressman]

Hmmm... This isn't very much flex for a Supra... Tom and I have achieved at least twice as much flexure during launch as this. Of course, I finally over-achieved on my original Supra. I now have #149 in the air. I've only winch launched it, haven't hand towed it yet. Has a bunch of improvements compared to my old #34. We will see how it holds up next week!

Joe

PS Also have a new Icon that is the same weight as #149. Interesting to switch back and forth between them. Some things are similar, some are very different.
What models will you be flying in Martin? Tom Gressman

[Stan Myers]

There have been some Kenndy Composite Supras lost recently due to structural failure on F3J two man tow launches. I believe these were the full carbon versions flown by very prominent pilots. I have just started building my glass version which will be used for TD only. My question is, is the glass Supra holding up well for those that are flying them in TD only. I know they fly nice, just wondering if I should be concerned about the longevity of the plane under normal use. I haven't heard/read anything from Kennedy regarding the exlposions occuring to our USA F3J team members' Supras. What's the verdict?

Clay

Clay, I've got #91 and just a sport flier. The plane is just super. It will launch nicely with 5mph wind with 15#'s of pull on histart. In 0 wind I use my mega histart and pull 30#'s goes strait up. with 5* dihedral joiners its a "pussy cat" in the air. Rudder is very effective use it almost exclusively for thermally. Just buy it and enjoy.

Stan

[Jurgen]

I'll have to be careful. I have number 32. :)Maybe you can ask to send it back and get another better build in return at minimal cost (or better only postage cost)? Will manufacturer take a degree of responsability of development?

There is a difference in fine-tuning-developments and serious construction shortcomings in early production stage. Client pays all they way in first, so why not coming the manufacturer half way back so the load of development is shared load.

In the world i dream of the manufacturer sends letters (or emails) to all their customers for fixes they can do theirselves. For more inherent matters a proposal for item interchange.

Top quality sailcraft deserves top quality service. I rest my case :)

Jurgen.

[ClayH]

For preventative measures, I filled all the gaps that I could get epoxy into between the top CF wing saddle sheet and the the pod. I also worked epoxy into the small gaps around the threads in the pylon.Then , working from the open end of the rear of the pod, I turned the pylon upside down and put some epoxy/micro balloons onto the bottom of those threads from inside the fuse, making a kind of epoxy bridge. You've got to leave room for the ballast tube, so that rules out going all the way to the bottom of the fuse as a fix.

I like the idea that Mark had about drilling across the pylon so you can run a dowel just under the wing bolt threads then tap that dowel for extra support. But I don't think that there is enough room between the bottom of the brass threads in the pylon and the ballast tube to do that fix. Maybe I'll just drill thru the bottom few threads so that a 3/8" dowel might fit.

I'm going to be pretty upset if my wing comes off after all this.JW; if you get a chance to reply, I'd like to know exactly what improvements have been made in your 2nd Supra. Good luck at the Worlds!

CH

[ClayH]

Before I mess this mount up, I was wondering if anyone could tell me a good way to get the stud out of the V mount before I strip the threads. I could double nut it, then back out the lower nut I suppose. Just want to make sure I don't hurt the mount.

Thanks to all who've responded to the thread. I know several other guys building molded supras right now that will benefit as well.

BTW, I used the ppushrods that came with my Supra in my Ava build. Does anyone know where I can get the same type pushrod besides Kennedy. I understand he's out of town now and I don't want to wait for him to get back.

Clay

[POF]

BTW, I used the ppushrods that came with my Supra in my Ava build. Does anyone know where I can get the same type pushrod besides Kennedy. I understand he's out of town now and I don't want to wait for him to get back.

Clay

Denny from http://www.polecataero.com/ got some pushrods. I'm not sure if you will find them on the website but try to ask him.

[joesoar]

Although Barry is in Martin for the WC, his wife (Karen) is running the shop and taking care of filling orders.... Just order it via their online form and follow-up with an e-mail...

Good luck...

Joe

[ClayH]

CST has .050 and .070 pushrods for sale. Which would be the better choice for internal routing? Will the .050 be stiff/strong enough for use in the Supra?

Clay

[Stan Myers]

CST has .050 and .070 pushrods for sale. Which would be the better choice for internal routing? Will the .050 be stiff/strong enough for use in the Supra?

Clay

Check your email

[peterkim2]

I have the fiberglass Supra 85#.
I've been taken it easy since I saw Larry Jolly's come off at one of our contest. I've had no hard landings or crashes. Well maybe one crash after the stab came of at telephone pole height . :censored:

I have a pod and boom on order. I should have done the upgrades.

[ploof]

Hey there, Peterkim2

I was wondering it what way did the stab detatch, was the V-mount structure, or the fastener?

I'm in the later part of having one ordered, and would like to know what I could possibly do to strengthen a possible weak spot.

Thanks, Ploof

[peterkim2]

The stud pulled out.
It has metric threads, very small. Looks like it just pulls out of the carbon v mount. Some guys are replacing the stud with 6/23. The threads have more bite. I got one PM about cutting a slot in the bottem to put a 6/32 nut in .
Sounds better than my idea of trying to put a bolt in upside down so the head will anchor it down. Mine was the thrid one I seen come off.

Great plane, just got it dailed in. Just a few weak points.

[peterkim2]

Sorry 6/32.
:D

[cody303]

The stud pulled out.
It has metric threads, very small. Looks like it just pulls out of the carbon v mount. Some guys are replacing the stud with 6/23. The threads have more bite. I got one PM about cutting a slot in the bottem to put a 6/32 nut in .
Sounds better than my idea of trying to put a bolt in upside down so the head will anchor it down. Mine was the thrid one I seen come off.

Great plane, just got it dailed in. Just a few weak points.


The new Supra's have this problem fixed. I have Supra 145 and have pounded it on landings and have had strong F3J Tows with it and have not had a problem.


Little Cody

[ploof]

Right on thanks alot.

[ClayH]

Cody,

Does that mean that there's a new v mount being used now?

Congrats on your outstanding performance at the Worlds. Were you flying the Supra there?

Clay

[cody303]

No its the same v mount they just put the stud in deeper. I didn't use the Supra in the worlds, but i used it in the martin cup.

Little Cody

[glderguy]

Sort of off topic a bit, is it true Arend Borst was flying a Supra fuse with Icon
wings/stabs at the worlds??
Walter

[cesarf3j2]

Sort of off topic a bit, is it true Arend Borst was flying a Supra fuse with Icon
wings/stabs at the worlds??
Walter

I´m not sure it was Arend Borst, but it was someone of the Canadian team.
There is a picture of that somewhere in the WC site.

César

[cesarf3j2]

Thats the picture I was talking about.
Looks nice.

[glderguy]

Could that be Skip Miller talking to AB holding his Iconized Supra?

[cody303]

Yea Skip called for him during the fly offs

Little Cody

[mnluz]

If I'm not mistaken Arend SupraIcon was built for very light conditions. He did not register it for the the Martin Cup to save it for the WC. The supraicon was his primary for light conditions.

For most of the rounds he flew a supra with a carbon center section and glass wing tips. This version seens like the best as an overall condition airplane and the plane he trusts for 90% of the flights.

Most of the rounds we flew with reasonable wind, guess this why he did not flew with the supraicon a lot in Martin.

He also had a very light supra as 4th model, but looks like he prefers the light Supraicon for light conditions than the light supra. Guess something to do with wing loading and the Icon super floating ability.

[Kevin Matney]

Hi
I was the luckly dog that won the raffel for the Kennedy Composites Supra.
I need help to set up a JR 9303 in it. Barry said the bird on the way.
I will be mostly Thermaling with it.

[torcgolf]

i just started to build #57. sounds like i have one of the 1st gen ones. im planning to do both the pylon and v-mount reinforcements but before i do, can someone please post pics? i have a good understanding of what to do but just in case i'd like to see the end results. knowing me, i might over do the reinforcements and endup adding a bunch of weight :o

one other thing, someone mentioned adding "vertical grain balsa" to the servo bays to prevent more flexing. do you mean boxing or framing the bays? i'm thinking about doing this too.

one think i'm thinking about is, im just a weekend sport flyer and switch between a histart and a club winch. i'll prolly never do any 2 man tows (at least not with this supra). given this, do i need to perform all of these updates?

thanks for the advice.

[torcgolf]

thanks for the pm's... i managed to maiden my supra today. the thing flew very mellow with the 5 deg joiners. test glide flew about 60yds (easily gone further but i didnt feel like chasing it), 5 total flights in off a shorty bungee. first 3 were testing CG (at 92mm) and trim. 4th flight was about 40mins! 5th flight was to test out my butterfly/landing settings.

i give it a 2 thumbs up.

[ClayH]

ey Torcgolf,

Did you receive any input about reinforcing the servo bays based on your planed use? I'm at that point on mine too.

Clay

[torcgolf]

hi clay. nothin about reinforcing the bays. what i ended up doing was potting the servos in the bays. it's pretty snug. im using airtronics 94761z's. if you are going with some thin wing servos you could lay down some CF sheet 1 or 2mm and then pot them in.

[joesoar]

As part of the Supra mods I did, I added a vertical grain balsa rib between the top and bottom skins just outboard of the airleron servos for increased torsional stiffness...

Joe

[ClayH]

Just thought I'd drop a line that I'd maidened my Supra #30 this weekend and so far so good. I reinforced the pod wing platform and wing bolt threads, re-inforced the v-mount with a longer bolt that now has a nut on it under the platform,and ran the pushrods internally. My plane came out to 61 ounces using Phil's tailset,94761 servos all around, a 4 cell 2/3A 1400 mah pack and the new JR 720 Synthesized receiver. Plane required 1.25 ounces of weight in
the nose to balance.

Did about a dozen winch launches, ranging from easy-no-dive to aggressive ping with massive climbout and no problems at all. It is a bit unnerving to see how much the wing flexes,but if Dr. D says it's supposed to do that, then I'm satisfied.

After about 2 minutes I was completely comfortable flying the plane - it was turning like I'd been flying it for months. Indicates lift very well, moves out when put into reflex, and slows down very nicely on landing. I've got about 3 hours on it now and it is definitely a keeper.If you want your 3 meter to fly like a good DLG, get a Supra. BTW, the Airtronics 94761 servos are outstanding.

Lastly, I had several occasions to contact Barry for parts during the end of my build and his response and quick shipping were outstanding. Thanks, Barry.

Clay

[ClayH]

My CG is set at 100mm right now and my plane is still has strong positive pull out of a dive test. 92 mm from the leading edge is the recommended CG. Is anyone else experiencing this?

Clay

[POF]

My first CG was at 92-93 mm from LE for the first 10 starts. To make it flying by itself in thermals, I added 10-15g in the nose. Funny how much so little can do to a glider.

Mine is #160 and I didn't enforce anything. And I’m sure that my Supra is pretty strong:O)

[markdrela]

My CG is set at 100mm right now and my plane is still has strong positive pull out of a dive test. 92 mm from the leading edge is the recommended CG. Is anyone else experiencing this?
On my bagged Supra, the 92mm position gives a very slow pullout when the elevator trim is set for a rather fast glide. The pullout is fairly fast when trimmed for min sink.

[Kevin Matney]

I was the luckly dog that won the one from the FIA F3B team
How do I tell if the mods are done to mine

[spatial]

Looking back at earlier posts in this thread,#57 and #85 were pre-mod ships so it seems extremely unlikely the changes would have been made on #50.

If the model had been put together prior to it coming into your hands it's probably worth checking the details of the pylon and stab mods to determine if the mods have been performed.

[eye_rc_soar]

I was the luckly dog that won the one from the FIA F3B team
How do I tell if the mods are done to mine

It is easy to see if the fuselage pylon bolt reinforcement has been done. Look down the balast tube hole in the fuselage, if you see two aluminum rings to capture the balast tube below each wing pylon nut - it has been done.

The new wing spar reinforcement was not done until about #148.

The v-mount fix is easy to do yourself.

Don

[Kevin Matney]

Thanks for the info I will check.
If I need to do the mods were do I find them?????

[Bob McGowan]

The new wing spar reinforcement was not done until about #148.


Do we think with the new wing spar reinforcement and the other mods, current production Fiberglass versions are up to the task of hard 2-man tows?

[mnluz]

Do we think with the new wing spar reinforcement and the other mods, current production Fiberglass versions are up to the task of hard 2-man tows?

Hi Bob,

I saw Arend Borst lauching his "new" supras on the f3j WC and if a plane can survive that I guess it is safe for most pilots. Carbon center section with glass tips. Soaring masters was quite a test for the supras too, so I heard.
I flew with the "old glass" version most of the rounds on the WC (hand tow) and the plane still in one peace. For severe conditions I had a second glass supra that I upgraded with a carbon center section.

When I got back home I worked a lot on my launching technique because I noticed how poor my launch was compared to the top pilots. That is the problem of living in Brazil…. Too many thermals, all year good weather… so you don’t pay too much attention to your launch till you have to do it in the rain, at 7 P.M. against great pilots. Actually, so many beautiful women around here that is quite difficult to pay attention to little planes. ;) :p :confused:

Getting back to business….now I’m getting much more tension (extreme) on the line and I was able to flutter the grass supra on light wind. Tested the same plane with the carbon section on light and even strong wind and no flutter. Wing torsion seems to be the problem.

I have the old and the “newest” versions at home. The new one has a subspar/rib on the tips and the horns are in a higher position… so the aileron flutter is figured out already. I will do that on my old supra and the problem will be solved.

If you are planning to buy a supra #150 or over you have all the testing and improvements made/suggested by top pilots on it. Arend and even Vladimir launches were as hard as a launch can be and the supra did ok.

If you have an early version, the stock glass version is not recommended/suitable for f3j and you will probably have to do the improvements discussed on this thread by yourself. I would not have used it on the WC if I could launch the way I can today.
Improvements are not difficult to do but recommended as we sometimes forget how dangerous this hobby can be. Depends on how extreme you are going to push your supra.

It is the best plane I ever had and I’m planning on keeping it….actually I just sold my superior carbon 80 that I had for really, really severe conditions with the addition of the “new supra” to the hangar. :D

[Kiesling]

I agree with Marlon (Hi Marlon!).

I think the new glass Supras should be fine for a hard 2 man F3J tow. Of course, as with any model, you need to make sure you do a tight radio installation. From what Marlon says the new versions may have the recommended subribs around the servos. This ties the upper and lower skins together and gives a MUCH stiffer servo installation. Without this, even the carbon wings were fluttering. For some of the early carbon versions the flutter may have been worse due to the added mass.

So if you're Supra does not have sub ribs on each side of each wing servo then you want to make sure you add them. I have heard of people that glue the servos to both the top and bottom skin and not use sub ribs. This has the same effect. I have not tried this method myself, but have been told it works.

I also recommend using JR 368's all the way round. They will fit for the ailerons - you just need to cut the lugs off and slide them all the way to the spar. There may be a slight bulge in the servo cover, but nothing to worry about.

Tom

[torcgolf]

speaking of subribs... what material are you guys using? spruce? balsa? on a side note, now that people have had more stick time on their supras, which joiner do you guys use/like and why? i been using the 5 deg just cause i like the upsweep but would like to hear the different characteristics between the 0, 2.5 and 5 deg joiners.