Speedwing extensions

[High Country 69]

So I'm hoping to start my wings soon and am now having more ideas and can't seem to decide whats best. I currently have the speed wing kit with the .065 spars. I want to get 1050 lbs MTOW and still get reasonable performance out of it. I like the idea of keeping the wings short so i will not have to build as big of a trailer to keep it in. On the other hand i want good performance out of it at gross. I have a Rotax 532 at this time that i plan to use but eventually want to replace it with a 582. I'm shooting for around 550lbs empty weight. I have already welded in gussets for the rear spar carry through tube and will be putting plywood in the bungie truss. I've spoke with Brett and have decided to go with his 13 gal wing tanks and will have to use his STOL transition ribs for the root rib and the one just outside of the gas tanks then it will be the speed ribs out to the end. Am i safe to just go this route and get 1050 lbs (not concerned about whats "legal" just whats safe) or do i need to extend the wings. If I was to extend them would i be better off just replacing my spars with longer ones rather than extending the ones i have? Last question (for now) am I ok with the wide rib spacing for 1050 gross or should i go with the HH spacing to be safe. I want to do it right the best that i can but i also just want to fly as soon as i can. sorry for all the questions but i don't have any extra money and want to get it right the first time and there doesn't seem to be a whole lot of info about the speed wings. If anyone has construction pics of the speedwing extension that would be awesome.

-Robert-

[efil 01 74]

So I'm hoping to start my wings soon and am now having more ideas and can't seem to decide whats best. I currently have the speed wing kit with the .065 spars. I want to get 1050 lbs MTOW and still get reasonable performance out of it. I like the idea of keeping the wings short so i will not have to build as big of a trailer to keep it in. On the other hand i want good performance out of it at gross. I have a Rotax 532 at this time that i plan to use but eventually want to replace it with a 582. I'm shooting for around 550lbs empty weight. I have already welded in gussets for the rear spar carry through tube and will be putting plywood in the bungie truss. I've spoke with Brett and have decided to go with his 13 gal wing tanks and will have to use his STOL transition ribs for the root rib and the one just outside of the gas tanks then it will be the speed ribs out to the end. Am i safe to just go this route and get 1050 lbs (not concerned about whats "legal" just whats safe) or do i need to extend the wings. If I was to extend them would i be better off just replacing my spars with longer ones rather than extending the ones i have? Last question (for now) am I ok with the wide rib spacing for 1050 gross or should i go with the HH spacing to be safe. I want to do it right the best that i can but i also just want to fly as soon as i can. sorry for all the questions but i don't have any extra money and want to get it right the first time and there doesn't seem to be a whole lot of info about the speed wings. If anyone has construction pics of the speedwing extension that would be awesome.

-Robert-

for myself, i would ask :

strut thickness enouth?

spar thickness enouth?

i don t have an answer, but i know the biggest stress on spars is near the strut attache, so tip wing kit extension vs long spar is not a problem for you.

[EDMO 1078]

The KF5 has the .065 spar, and 18 inches between ribs. 1400 or 1550 GW. The Magnum uses 12 inches and .083 for 1700 GW.

One inch struts should be minimal for your 1050, better yet, 1 1/4, IMO.

I don't know what Avid did, but Kitfox increased the size of the crossover tubes as GW went up.

Mine are 1 1/8 x .049 wall.

Ed in MO

Edited 8 Mar 2012 by Ed In Missouri

[High Country 69]

So I'm thinking about just replacing the spars with HH spars this will give me the extension and thickness .083 that i need then I'm thinking I will just use speed wing ribs on them but give them the closer spacing of the HH wing. This should give the strength, with reasonable STOL and speed performance and i will not have to replace all my ribs. good idea, bad idea?

-Robert-

[efil 01 74]

So I'm thinking about just replacing the spars with HH spars this will give me the extension and thickness .083 that i need then I'm thinking I will just use speed wing ribs on them but give them the closer spacing of the HH wing. This should give the strength, with reasonable STOL and speed performance and i will not have to replace all my ribs. good idea, bad idea?

-Robert-

no good as my mod but good !

i may try to reduce washout to avoid negative aoA of wingtip in level flight

[birddog486 21]

I'm in the process of finishing up the second wing on my model c Aerobat-speedwing and I decided to put 3' extensions on. I'm hoping to have the best of both worlds. Unfortunately after 22 years we just noticed the kit was shipped with 3/4" struts instead of the 7/8" that were ordered and included on my parts list.

[dholly 718]

So I'm thinking about just replacing the spars with HH spars this will give me the extension and thickness .083 that i need then I'm thinking I will just use speed wing ribs on them but give them the closer spacing of the HH wing. This should give the strength, with reasonable STOL and speed performance and i will not have to replace all my ribs. good idea, bad idea?

-Robert-

That's what I did.

[High Country 69]

Did you also use the 13 Gal wing tanks that Brett sells? That is what I'm planning to use but Brett thought i may have to make some strips of wood to glue between the tank and the fabric. Have you gotten this far yet? I ordered my new spars and the extra ribs from Brett so I'm just waiting for parts to start my wings. Brett also suggested that i use the standard ribs with the tails just as the original HH wing had then i can try using the flapperon close to the fuselage and if i don't like it i will have the extra mount out at the end and he makes a kit to just move it over. then i don't have to extend it. What have you done regarding the flapperons. pics would be great. Nice to know I'm not the first guinea pig

-Robert-

[EDMO 1078]

So I'm hoping to start my wings soon and am now having more ideas and can't seem to decide whats best. I currently have the speed wing kit with the .065 spars. I want to get 1050 lbs MTOW and still get reasonable performance out of it. I like the idea of keeping the wings short so i will not have to build as big of a trailer to keep it in. On the other hand i want good performance out of it at gross. I have a Rotax 532 at this time that i plan to use but eventually want to replace it with a 582. I'm shooting for around 550lbs empty weight. I have already welded in gussets for the rear spar carry through tube and will be putting plywood in the bungie truss. I've spoke with Brett and have decided to go with his 13 gal wing tanks and will have to use his STOL transition ribs for the root rib and the one just outside of the gas tanks then it will be the speed ribs out to the end. Am i safe to just go this route and get 1050 lbs (not concerned about whats "legal" just whats safe) or do i need to extend the wings. If I was to extend them would i be better off just replacing my spars with longer ones rather than extending the ones i have? Last question (for now) am I ok with the wide rib spacing for 1050 gross or should i go with the HH spacing to be safe. I want to do it right the best that i can but i also just want to fly as soon as i can. sorry for all the questions but i don't have any extra money and want to get it right the first time and there doesn't seem to be a whole lot of info about the speed wings. If anyone has construction pics of the speedwing extension that would be awesome.

-Robert-

Robert, Please read my post that I put on your "FOR SALE" post about selling your parts.

ED in MO

[High Country 69]

Thanks for the heads up Ed but after speaking with Brett we decided that this was the safest route to go. He said that the KF's get away with the .065 spars by using a big aluminum insert to reinforce it. I discussed this route with Brett but we decided that it wouldn't save any money or weight so i would rather send my money to Airdale. and as for the heaver fabric i had the lighter stuff on my skyraider and poked small holes in it when turning around at the end of my airfield and the brush there is really not that bad. I've thought of mixing up the light fabric with the heavy fabric but think its just best that I use all heavy. If i was to use light fabric for the top sides how long do you think it would last before it needed replaced again?

-Robert-

[EDMO 1078]

Thanks for the heads up Ed but after speaking with Brett we decided that this was the safest route to go. He said that the KF's get away with the .065 spars by using a big aluminum insert to reinforce it. I discussed this route with Brett but we decided that it wouldn't save any money or weight so i would rather send my money to Airdale. and as for the heaver fabric i had the lighter stuff on my skyraider and poked small holes in it when turning around at the end of my airfield and the brush there is really not that bad. I've thought of mixing up the light fabric with the heavy fabric but think its just best that I use all heavy. If i was to use light fabric for the top sides how long do you think it would last before it needed replaced again?

-Robert-

My last light fabric was 20 years old when I tore it off. It was still solid.

Course, poking holes in it might have made a difference.

Most of all is the UV blocker and paint, and keeping it clean, I guess.

We warped the root rib on the J3 with the 2.7, and had to repair and brace it.

Stewart was adimate when he advised me NOT to use it on the Kitfox.

Ed in MO

[Bandit 286]

I used heavy fabric on the belly and light fabric on the rest of the airplane. Everything looks like new except the belly fabric.

[EDMO 1078]

I used heavy fabric on the belly and light fabric on the rest of the airplane. Everything looks like new except the belly fabric.

I could understand it doing that. However, the 1.7 is a tighter weave, and might actually be tougher. (Don't have any proof of that)

The 2.7 takes more UV and paint to finish, so is heavier than just the 1 ounce difference.

Stits recommended the 2.7 to me, but Doug or Dan Stewart said, "NO WAY!" Go figure!!!! Make your own "best guess".

Ed in MO

[High Country 69]

I used heavy fabric on the belly and light fabric on the rest of the airplane. Everything looks like new except the belly fabric.

How old is your fabric and which "system" did you use to cover it with. Also why do you think the belly fabric is not so good, just because of off airfield landings or do you think its a problem with the fabric. if you were to do it again would you change anything? Sorry for all the questions

-Robert-

[Bandit 286]

I should rephrase what I said. The fabric is ok, but it flutters some between the landing gear legs which causes some cracks in the polytone. The worst problem has nothing to do with the fabric, but after about 900hrs of 2 stroke residue blowing on the belly fabric, it is solid black with exhaust residue. I'm not real good at keeping it clean.

Edited 18 Mar 2012 by Bandit