Need help with mods to hangar trusses

[Kiddo's Driver]

If it were mine, I would fashion a piece of high density foam to slip over the top of the vertical stabilizer after it's in the hangar; this way, in the event of an untimely nose strut decompression, the contact between the tail and the ceiling would be gentle and non-damaging.

Not a bad idea, but I pull it in and out with the pallet jack. No issues with just keeping it on there. It is easy enough to slide the thick board under the forks right after I pull it in.

 

[timwinters]

It fits!!!
With all wheels on the ground it just clears the ceiling, maybe 3 inches. Of course that means that if the front strut goes flat it will damage the tail...

I might still be inclined (pun intended) to screw a 2x6 down to the floor for the nose wheel to climb up on to, with a long bevel on the approach end to lessen the force needed to climb it. The end of the 2x positioned so that the nosewheel is on top of it just before the tail enters the hangar.

Then, screw another 2x6 down on top of that one for the last 1/2 of the length, again with a long bevel on the approach end.

The two would raise the nose 3"...how much would that lower the tail? If not enough for a "warm fuzzy" then you could add a third layer...in three equal steps.

 

[Kiddo's Driver]

The two would raise the nose 3"...how much would that lower the tail? If not enough for a "warm fuzzy" then you could add a third layer...in three equal steps.

The math works out to 1.75 times the front tire height, but that does not really matter. I would just need to raise the front by the worst case change in height cause by the deflation of the front strut and front tire. I would need to see how much of a change the front strut and front tire going flat would cause. Maybe 8-10 inches, so the ramp would have to raise it 8-10 inches to compensate for a worst case failure.

Hummm....my pallet jack only lifts the front wheel by 4.75 inches. I better go measure and make sure that is enought for the worst case listed above!

Jim

 

[timwinters]

BTW...now that I think about it more...I'd probably use wider boards, probably at least 2x10s. The nose tire sliding off the side of a 2x6 would probably be a major malfunction.

I guess you're planning to pull the plane in, then jack up the nose, and keep it supported?

 

[JHW]

the easy way to make sure the tail doesn't rise is to tie the tail down. Make yourself a fixed length cable with hook and put an anchor in the floor. Pu hook into tail skid ring and it isn't going to hit the roof regardless of what else happens.

btw kudos for giving it a try to see if it will fit. be careful, cherokee main struts like to stick extended sometimes.

 

[Alexb2000]

Maybe there is something wrong with me, but I would just fix the problem.

If that building is free standing it would be a one day job to raise the entire roof structure. No need for engineering, trusses, excavation, etc. Just build temporary walls on the inside to take the roof load, jack it up with bottle jacks, and add framing to the top of the existing walls. No biggie.

I would compare that effort and less than $500 against the probability of whacking the tail someday when I wasn't paying attention or some part of my nose wheel lifting plan didn't work.

 

[Kiddo's Driver]

Not my hanger, I am renting the property that includes 3 acres of land, a pond, the house and the hangar/shop complex. If I OWNED it I would change it. Heck I would probably just add 10 feet to the front of the hangar and make sure the addition had a higher ceiling.

Jim

 

[Kiddo's Driver]

BTW...now that I think about it more...I'd probably use wider boards, probably at least 2x10s. The nose tire sliding off the side of a 2x6 would probably be a major malfunction.

If I go this route I will build sides on the ramp to make it more of a track.

I guess you're planning to pull the plane in, then jack up the nose, and keep it supported?

Currently I pull it in with the nose raised 4.75 inches using an electric pallet jack. The pallet jack has a nose wheel attachment that holds the wheel in place between the pallet jack forks. I pull it in on the pallet jack and then I put a 4x4 and a 2x4 under the forks so that the nose cannot be lowered. This keeps the tail down and it keeps from extending the nose strut (this should keep it from getting locked in the extended position).

Jim

 

[Alexb2000]

Not my hanger, I am renting the property that includes 3 acres of land, a pond, the house and the hangar/shop complex. If I OWNED it I would change it. Heck I would probably just add 10 feet to the front of the hangar and make sure the addition had a higher ceiling.

Jim

Check. You started out asking about truss modifications so I assumed some construction was on the table. Assuming the owner would allow some changes I would still weigh a couple of hundred in lumber vs. the risk, deductable, loss of use, devaluation, etc. if something goes wrong.

 

[Kiddo's Driver]

Check. You started out asking about truss modifications so I assumed some construction was on the table. Assuming the owner would allow some changes I would still weigh a couple of hundred in lumber vs. the risk, deductable, loss of use, devaluation, etc. if something goes wrong.

Good point. Back when I started this thing the owner was thinking about modifiying to make it fit. We didn't need to, so it went out of my mind.

Jim

 

[Kiddo's Driver]

Update:
Shocker, Wikipedia was off on this number. They said 10' 6". The Pilot's Information Manual says that it is 9' 10". The ceiling ended up being 9' 6" inches, so I only ended up having to lower the tail by >4 inches.

The pallet jack that I have to move the plane around works great. I slide a 4x6 inch board under the forks when I park it just encase the hydraulics fail & it tried to lower the forks to the ground.

Now that winter is here I really wish it had a door, but am thankful for the three walls & a roof!

 

[Kiddo's Driver]

More info on where the 10' 6" comes from. If the mains are fully inflated and if the nose strut is completely deflated, the tail will end up 10' 6" in the air.

Luckily I noticed the leaking front strut before I pulled the plane in to the hangar. I parked it with the tail sticking out.

Getting the strut fixed...