Lukeh

I have been to the airport today. On the loose hinges (the two on the outer edges of the wings) bushers tilt around the axis and they are pretty loose. On good ones, mostly the nut and castle nut rotate together with the flaperon (but they are not fixed/tighten to the flaperon, only there is more friction, so they follow the move). I am not sure if the bushing rotates as well. The bushing is NOT tightly sqeezed against ANY bracket and it can not be, because the screw is tightened just against the washers, washers ID is bigger than OD of the bushing and there must be some axial free play left. Basicaly anything can rotate and nothing is fixed. Funny. I made a video, but I am not sure if I can put it here directly, the 47MB one fails to upload. I spoke to my technical guru, it seems he has more different ideas how to do it and have not decided yet, I must wait and see. For sure he wants to have bushing fixed to the brackets, perhaps two short bushings one from each side, bushing rim wider than the original bushing for better axial stability, pressed from outside to each bracket, possibly additionaly secured in some way against rotation. Put the screw through it, not tight, so the bushings will rotate on the screw. Additional idea is to rivet a piece of the metal sheet to the brackets first, to make them thicker. 20260918_172443 - Trim.mp4

My technical guru wants to do it other way - the one when nothing moves against the aluminium brackets - that means to have two brass tubes outer and inner, each fixed to one of the brackets, bolt going through the smaler tube (if I get it right). He says, he has done it that way before, on the Zenair STOL CH 701. I will share the details when I have some.

As a side note, what is your take on lubricant? Many recommend PTFE dry spray (I did order one already), ICP says lithium white grease. Which is better? Any experience on this two? I lean to the PTFE spray.

@Kyle Communications Still, in the sfGnome pictures - the extended rim of the busher SC210 lay directly on the castle nut and screw head lay directly on the wing hinge. It would seem to me, that neither should move against each other, busher against the wing hinge, nor the screw against the busher. And flaperon hinge does move/rotate against the buhsher outside. Aluminium hole in flaperon hinge rotates on brass busher. Explain, how this understanding is wrong?

to add to the confusion there is even different manual, showing different ICP setup. Probably older version, that JG3 have had. https://www.aircraftpilots.com/forums/topic/35271-improved-aileron-bushes/page/2/?&_rid=12414#findComment-447599

Kyle I don't see it. This is from maintenance manual - the original bushing installation. The head of the screw seems to touch the bushing directly, pressing it to the left bracket. How can the screw rotate inside of the bushing? Besides, the bushing's OD is 6mm, it goes through both brackets, AN4 washer has ID 0.265 inches (6,7mm)... This gets weirder and weirder. I probably will not understand until I dismount it and see. I looked it up in the Italian printed construction manual now and it does not make it easier. For example they say the bushing is mounted from the inside and screw from the outside of the aircraft (always), but the brackets have different order on inside hinges to the order of outside hinges.

Thanks Kyle. I am afraid you made me confused even some more. I was convinced after long thinking, that the original bushing is by the bolt fixed to one of the hangars let's say to the wing one, wing-bushing-bolt are connected and do not move, while the other hangar (flaperon) rotates around the outside of bushing aluminium on metal. I could not get my head around this but that is how I undestood it. Not that the bolt rotates inside of the the bushing or bushing around the bolt. But you seem to suggest the later.

Hi, @JG3 I am still confused. In your initial drawing, the bolt, stationary support, bushing and nut are all fixed, do not move? The aileron bracket rotates on the outside of the bushing and the washer, first from the left ... it bears against the bushing so that the nut pushes bushing against the stationary support and aileron bracked still can move with some axial play? Did not bushing compress in time? And what's the buzz about different diameters in versions of Savannah? On my Savannah I have a 6mm hole in the aluminium parts ... that is no good for AN3 bolt through the stationary support? Did you have smaller diameter on both and just enlarged the aileron bracket hole to 8mm?

I noticed a discussion on alternative bushing, made from bearing-grade polyester (PETP-GLD130 ‘TX’ , Sustadur PET GLD 130) or such. I was hoping some of the participants would share their experience and approach they used, as the thread contains more different paths and suggestions and not much feedback from the real use? @JG3 ,@IBob , @Kyle Communications , @facthunter , @FIL65 , @eightyknots , @dan tonner ? (sorry for spamming you)

Thanks, I understand using the PTFE spry is recommended now. ICP suggest "White grease, Renolit ZT2". Unfortunately I did not notice in time and have problem on two outer flaperon hinges now. I will greese remaining hinges ASAP.

I noticed free play on both outer hinges on Savannah S. Will I need to change bushing and pin, or could there be a more serious problem concerning metal parts of the wing and flaperons? Anybody has done this?

Excelent! I want to buy a kit 2nd hand and don't have the build manual yet, but this could be way to go, I will ask the seller about it.

Neil, is there a parachute in 310,5kg?

Hello, none of the pdf links is not working for me. Is there any way I could get the document? Perhaps Email? Thanks and best regards, Ludek.

Please, anybody in any country who has registered Savannah S as a homebuilt with MTOW 560kg or 600kg, would you have any documentation related to the project design that supports 560 or 600kg MTOW ? The kit is manufactured about 2018 and it has MTOW 600 on serial number plate, but I have trouble getting any related documents from the ICP. It is no longer possible to register under the old MTOW 450kg rules here in Czech, the homebuilt with sufficient MTOW is the only option and I need some kind of confirmation to prove that the project was calculated for such MTOW.