Aluminum gear

Bartman said:
If the Decathlon wings save thirty pounds, thereby lowering the empty weight by thirty pounds, and they increase max gross by 100 lbs, that's 130 pounds added to the useful load. You're saying they come in heavier, my Milman conversion left me lighter where everyone says they're heavier, so I'm not sure we can resolve this and I've already had to use the word "thereby" so I defer on the matter.
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I need to recast this because in no way did I mean to be a jackass. I have always been under the impression that aluminum wings were heavier. If they're lighter, then that changes my opinion of them.
 
Bellanca Super D: empty 1330, MGW 1800, useful load 470, payload with full fuel 224 = me and a bag.

Current ACA Super D: empty 1304, MGW 1950, useful load 646, payload with full fuel 400 = me and a friend.
 
Big Ed said:
Bellanca Super D: empty 1330, MGW 1800, useful load 470, payload with full fuel 224 = me and a bag.

Current ACA Super D: empty 1304, MGW 1950, useful load 646, payload with full fuel 400 = me and a friend.
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Love it. Bellanca $50k ACA super D $300k. Now if I can just get my backseat friends to pay for it. (Asked my wife, she said she is not that good a friend).
 
Tangogawd said:
I've looked hard at aluminum gear for the gcbc, but then again, I already have 2 sets of scout steal gear that I could put on it...... goodbye useful load
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Will the Scout gear fit? They are much taller. My Scout sits much higher than the Decathlon. In fact I had to raise my T-hangar roof because the plane is so tall (stock 8.50).
 
Goodyear said:
Will the Scout gear fit? They are much taller. My Scout sits much higher than the Decathlon. In fact I had to raise my T-hangar roof because the plane is so tall (stock 8.50).
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the scout leg is also longer at the mount. Heard of 2 ways it has been done. Re-drill the gear leg to the citabria bolt pattern or the preferred way is modify the fuselage to accept the leg as is. I understand ACA sells a kit to beef up the undercarriage
 
Weight wise how much more would the Scout gear legs weigh? They are heavy.

I think Bartman suggested that a Decathlon leg weighed roughly 22# a piece. In that case I'm thinking 35# a piece for the Scout. Just a wild guess.
 
Getting pretty close to talking myself into aluminum gear. My steel gear are 42 years old and have 1700 hours of who knows what on them. From research, prop strikes and gear failures are not uncommon for these planes. Am liking the mental comfort factor of new, beefy, longer gear.
 
The aluminum gear for the Dec do not raise it. I doubt you would need extended gear on a Decathlon; it is simply not a rough country airplane.
 
Big Ed said:
Getting pretty close to talking myself into aluminum gear. My steel gear are 42 years old and have 1700 hours of who knows what on them. From research, prop strikes and gear failures are not uncommon for these planes. Am liking the mental comfort factor of new, beefy, longer gear.
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I'm not sure it's the steel or aluminum gear leg that fails.
IMG_20170618_100904-01.webp
I took this picture a few years ago and pretty sure I posted it here on this forum. It was pushed into the hangar with the warbird I flew at the time, and briefly shared space with my crusty (by comparison) Citabria. Later I would learn that this plane had a "gear failure" and was getting extensive repairs. I loved the paint scheme on that plane and the wood hangar just added a cool backdrop (trivia for those interested, this hangar is shown in the movie "Always" with Richard Dryfus and John Goodman, the movie with the great opening scene featuring a PBY, which is still at the airport to this day)
For bonus points it features either a Citabria or Decathlon (I can't remember), made to look like a rust bucket. In the movie it is shown landing near this hangar but is really landing on the taxi way, hundreds of feet from the actual runway.

For some reason I thought it was you (Ed) that posted pics of a prop strike and it has more to do with pegging the brakes at low speed while taxiing than any component failure. I had always discounted the possibility since my plane seems to sit quite firmly on the tailwheel, but one day I was horsing around getting into position on a busy run up pad and managed to experience the tail coming off the ground at a very low taxi speed when I dynamited the brakes. I reacted properly that day but let's just say "it's for real", and my plane's logbooks have a prop strike in the 2004 time period. I always thought the plane must have ended up on it's nose but the previous owner (who I know well) said it was never on its nose, leading me to believe it was a low speed taxi issue.

I suspect most "gear failures" are old style U bolts breaking or a significant enough ground loop to remove a wheel from the gear leg. I had my IA upgrade my gear hardware at my very first annual. Surprisingly (for me anyway), he told me he has seen a few failures but they were not at the corner of the U, but at the very first thread under the retaining nut.

Anyway, my plane is 15 years and 1000 hours older than yours and I have no concern the gear legs are going to break. I'm rocking the high dollar bolts and sleep like a baby.
 
Those definitely are steel gear legs.

The U bolts probably had "cut" threads. You absolutely know they were not 125,000 psi steel. That is where I would guess all the failures were - right there at the last cut thread.
 
Bob Turner said:
The aluminum gear for the Dec do not raise it.
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Bartman said:
I spoke to Dale at the factory today about the aluminum gear legs for the Decathlon
  • They're an inch longer than the steel gear
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If my old 1978 steel gear are worn out and sagging, fresh gear would raise the nose. Aluminum gear would raise it more.
aftCG said:
For some reason I thought it was you (Ed) that posted pics of a prop strike and it has more to do with pegging the brakes at low speed while taxiing than any component failure.
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I did post that, but in the same thread I described another prop strike in another 8KCAB I was 1/4 owner of. A student learning wheel landings over controlled on the stick forward after the mains touched. The gear flexed and the prop nicked pavement. This is not the first I have heard of that type incident.

Longer, stiffer gear would obviously help prevent wheel landing strikes. I think they might help avoid nose over strikes as well. An extra inch in height means the tail has to be higher for the prop to make contact.

I agree, most gear failures seem to be U bolt failures or terrain induced. However, I have seen enough pictures of gear snapping at the high stress bend just outboard of the U bolts to know it does happen.

The service manual specifies that gear legs should be replaced when negative camber exceeds 5 degrees. If that happens, the choices are reconditioned steel or new aluminum. I'm starting to think aluminum makes more sense.
 
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Did not know about the extra inch. I may still have the old legs; I will look.
On the low speed sudden brake application - I seriously doubt that extra inch will help.
 
Measured my wheel camber. Left is zero, right is 2.5 degrees negative (top inwards). Service Manual says replace at 5, so I have some time, but now that I know, it bugs me. Also, I checked my U bolts and I have the old style, which concerns me.

Looking at 3 options:
  1. Replace the bolts only.
  2. Replace bolts and replace gear with reconditioned steel.
  3. Replace bolts and replace gear with Aluminum.
I really like the idea of the AL gear. Longer, stiffer, cleaner. However, I don't like the idea of the extra cost. Also, I don't have a shop I trust for the frame and fabric work, minor though it is.

If I go with reconditioned stee now, I can always upgrade to Aluminum later. Wasted cost is only about $1K. Leaning towards that approach.
 
Get the U bolt replacement now. When you go aluminum you will only need longer bolts. I personally believe AN-7 bolts are plenty strong for the U bolt replacement, but go ahead and get NAS bolts for the center pin, and bite the bullet for longer ones in there when you go aluminum.
 
Big Ed said:
I saw a figure quoted for $6500, but that was from 2013. That is a lot of money. I could get the fuselage recovered for not much more than that. OTOH presumably the gear upgrade would increase the value of my plane, especially if I later got the wings for the gross increase.

If my current legs are damaged, the alternative would be a replacement spring steel set from Rainbow. Those are $800 on exchange, with an $800 core charge. I suppose the question would be what kind of labor cost am I in for.

I started paying attention to stories about Citabria spring steel gear legs bending. Turns out it happens a LOT. I found 6 or 8 instances on the internet with a cursory search.
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Hey. New UK member here - I don’t suppose you could help me with a lead for this Rainbow Ron guy? I have a bent right hand leg needs straightening…
 
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