Jack points and raising the aircraft

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Rainproof
Posts: 11
Joined: Fri Jan 03, 2020 9:55 pm

Jack points and raising the aircraft

Post by Rainproof »

My Ryan is in annual and will be an airworthy aircraft on completion EXCEPT the repair station cannot jack the plane to do the gear checks. The right wing internal receptacle/fitting for the jack point/tie down ring has cracked and the jack point cannot be used. Fixing that is an issue we're taking on.

In the meantime, has anyone ever used alternate means to raise one wing? My plane's left jack point is good, but if we can raise the right wing then the repair station can complete the annual items on the landing gear. IF that can happen then I'll proceed on to the problem of fixing the internal part of the jack point.

Rick
Zach8910
Posts: 13
Joined: Tue Oct 29, 2019 7:50 pm

Re: Jack points and raising the aircraft

Post by Zach8910 »

I’m pretty sure I’ve heard guys talk about just using a rubber pad and a small piece of plywood o. The jack point. I probably have the jack structure I can rob from a wing if that would help
Go work on your navion!
Rainproof
Posts: 11
Joined: Fri Jan 03, 2020 9:55 pm

Re: Jack points and raising the aircraft

Post by Rainproof »

Based on the damage to the internal part of the jack system, I think more pressure in the area will only aggravate things. That's why I was wondering about lifting / pushing the right wing up with pressure outboard of the landing gear. [im
Right Jack Point fitting 1.jpg
Right Jack Point fitting 1.jpg (81.44 KiB) Viewed 9479 times
g][/img]
billla
Posts: 32
Joined: Tue Oct 29, 2019 5:52 pm
Location: Seattle, WA

Re: Jack points and raising the aircraft

Post by billla »

I think the key here is to distribute the load along the wing rib that the "bathtub" type fitting that supports the ring. That fitting is essentially transferring load to the rib. So something that is aligned with the rib - maybe a longer jack pad that is maybe 3' long - would be how to approach it.

Hopefully someone can drill out a good bathtub fitting from a wrecked rib...
Rainproof
Posts: 11
Joined: Fri Jan 03, 2020 9:55 pm

Re: Jack points and raising the aircraft

Post by Rainproof »

That sounds right and I think I have a source for the replacement bathtub fitting riveted to the rib. I have a different photo that shows an interesting thing about the rib and the jackpoint fitting. The rib actually is wider at the jack point to provide extra loadbearing surface. To add to that, a plate or shim was added between the lower wing skin and the bottom of the bathtub fitting. Cecil Loter thinks that someone later in the production process realized that the area needed to be beefed up from the original configuration.
oldskydog
Posts: 15
Joined: Fri Nov 01, 2019 4:32 am

Re: Jack points and raising the aircraft

Post by oldskydog »

Jack up the airplane using the uplock bolt on the bottom of the strut with a floorjack or bottle jack. Slip a heavy duty padded sawhorse under the wing then remove the floor jack. Pump away for your gear check and reverse the process to put it back on the ground.
Rainproof
Posts: 11
Joined: Fri Jan 03, 2020 9:55 pm

Re: Jack points and raising the aircraft

Post by Rainproof »

I want that, as a matter of fact. My mech is not happy with the idea. You picture putting the padded sawhorse/lift just outboard of the landing gear on a rib?
billla
Posts: 32
Joined: Tue Oct 29, 2019 5:52 pm
Location: Seattle, WA

Re: Jack points and raising the aircraft

Post by billla »

Jacking by the strut is going to compress the strut, so just consider that the strut is going to drop the full extent of the strut rod - 7-1/2", I think. So make sure the sawhorse (or jack pad on a jack) is tall enough to take that into account.

You'll also need to very carefully coordinate the jacking to ensure you don't side-load the gear.

Any approach will work, just think it through and be careful :)
Rainproof
Posts: 11
Joined: Fri Jan 03, 2020 9:55 pm

Re: Jack points and raising the aircraft

Post by Rainproof »

So my plane(and Kevin Whiteside) has gone through the pain of going into the structure, manufacturing reinforcements, and installing them. IF anyone ever has the internal jack point structure damaged as mine was, we have the solution. NOW the annual is done and it's and airplane again.
oldskydog
Posts: 15
Joined: Fri Nov 01, 2019 4:32 am

Re: Jack points and raising the aircraft

Post by oldskydog »

Good news. Some day you'll have to give us the details.
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