Jacking up the airplane to change tires or whatever has always been a bit of a PITA. I've seen guys use floatplane lifting eyes, which are great if your airplane has them, or use an engine hoist with a sling around the engine mount. Hammer posted pics recently of how he can jack his up, using some of his high-strength line and an engine hoist.

I have used the tapered jack-pad units which slide up onto the gear legs, both home-made & mfr'd by Bogert, but they usually scuff the paint. Tried c-clamping a piece of 2x4 onto the gear leg & jacking against that, but it wanted to slip. The best thing I've used so far was something I made years ago. It was designed to be compact to carry along in the tool bag, in case of tire emergencies, but it works better than anything else I've tried.


The jack-pad consists of two pieces of 1x1x1/8" angle, 3-3/4" long, with two 5/16" holes at 2-3/4" center-to-center, along with two 5/16" x 1-1/2" bolts & nuts. The angles are wrapped in duct tape where they contact the gear leg, & the bolts have 1/2" long pieces of 5/16" ID vinyl hose around them to prevent scuffing the edge of the gear legs. I boxed the end of one of the angles, otherwise the corners tend to bend up where the jack bears against it. My little floor jack came up short in the elevation department, so I used a 1/2" drive 1" socket to give me that little bit extra.

We just did exactly what is shown in the top picture with a heavy duty nylong ratchet strap and engine hoist for putting on our 29" ABW's. We wrapped and tied the nylon strap snugly low on the gear - as you lift, it cinches further and the taper on the gear further tightens and prevents slipping. I was tottaly skeptical when we started, but it was rock solid.

Frankly what I want to do is modify the typical tapered jack pad to have lifting eyes on top, where nylon extension straps (like for tieing down a vehicle on a trailer) and us that to lift the gear, rather than jack from the bottom. Lift just seems like a safer method than jacking. If I get it fab'd and it works, I'll post pics.

I used to use a bottle jack, but with it being too short I put it on one or two 4x4 blocks. When the wheel first starts coming up off the ground, it usually gives a lurch inward, which tips the jack. Very disconcerting if you're not expecting it, as in OH SHIT! The floor jack being on wheels minimalizes this problem. I thought about trying Hammer's method, but I don't have an engine hoist and borrowing one or cobbling something up was more trouble than just digging the old standby out of the airplane tool bag. A come-along hung from the overhead would work fine, but I don't have one of those either. I wonder if a racheting cargo strap would work OK- limited travel but then again it doesn't have to go up too much.

emflys wrote:
Frankly what I want to do is modify the typical tapered jack pad to have lifting eyes on top, where nylon extension straps (like for tieing down a vehicle on a trailer) and us that to lift the gear, rather than jack from the bottom. Lift just seems like a safer method than jacking. If I get it fab'd and it works, I'll post pics.

I don't see that as any improvement over a suitable piece of line girth hitched around the gear leg. A girth-hitched line will not slip and only takes a couple seconds to attach and remove, verses fiddling with a jack pad.

Also keep in mind that the 1" cam straps made for securing motorcycles and the like are not very strong. I tested two, one inexpensive and one very beefy model and they broke at 700 and 1,100 pounds. That's not enough margin for me to risk using one lifting an airplane. The industrial straps used by tow trucks and the like are a whole different story, but seem like they would be very awkward to use.

I'm not sure what they're typically rated to but a hand cranked winch like those used to pull boats onto trailers would be pretty slick if it was strong enough. Rig it to a tripod made from suitable metal tubing and up you go.

Jacking from the bottom scares the crap out of me regardless of the interface. I've done it in the past and would do it again if I absolutely had to, but only then. An airplane cannot fall off a line lifting it from above.

Don't be so sure that it can't fall off a line lifting from above. I will always remember an incident that happened over 35 years ago when I was an apprentice sheet metal worker, a pipefitter I was working with needed to lower a Johnson bar down from a roof. A Johnson bar (in this case anyway) is a set of wheels & a metal prying edge mounted on about a 6' long wooden handle, used for jockeying a heavy piece of equipment around, and is not lightweight.

This guy threw a half-hitch and several wraps of hand line around the Johnson bar, but when he went to lower it down, the second he let go of the johnson bar itself it slid right through all the rope loops and down it went. OK, so he had the taper of the handle going the wrong way for the "girth hitch" to work properly, but the point is that mishaps can happen no matter what. I saw some guys drop an airplane after they hoisted it up using an engine hoist hooked to a rope tied around the engine mount-- that was an expensive lesson as to why you shouldn't ever use a granny knot.

Good advice, absolutely nothing is fool proof, given the proper fool to test it out.

I have done it this way more times than I care to try and count and have always had zero problems. This picture was taken just a few weeks ago, try to ignore the Oklahoma bug crop!

That's about what I have done in the past. I used two c-grip vice grips, I didn't have anything better, but they didn't clamp tight enough to prevent slippage. Looks like those pipe clamps do a better job, as probably would a pair of big old c-clamps. One big advantage of that 2x4 set-up is that you don't need any special tooling (welding etc) to fabricate it, just a saw, and another is that the position on the gear legs is infinitely adjustable. There's a sweet spot where the jackpad is far enough up the gear leg so there are no interference issues between the wheel & the jack, but close enough where the jack doesn't run out of height.

I might have to get a set of those pipe clamps, the huge adjustment for length makes them handy for a lot of things. Maybe just a cheapie set from Harbor Freight since they'll just be for once-in-a-while usage.

This is what I use: http://bogertaviation.com/products/lil-lifter-3 Makes quick work swapping between 6.00x6's and my 29' bushwheels. I use a cordless drill for the cranking... and their jack pad for the gear: http://bogertaviation.com/products/flat-pivot-point-adjustable-jack-pad

Some years ago I got our Skylane stuck in some mud on the Schloredt strip near Sundance, WY. Snow had been melting across the strip and turned about a 30' length of the strip into soft, gooey muck. I didn't see that until we had already landed, and we came to a sudden halt about halfway through the mud. My folks were there with their VW station wagon, so I put a chunk of board beside the main gear and used the VW's jack to the underside of the step, and lifted the main gear one at a time so that we could stick some old WWII landing mats (about 10' long by 2' wide) under each of the mains. I lifted the nose gear my pushing down on the tail.

Then I cranked it up, and firewalled it with the flaps down and full up elevator, and I had just enough headway that the mains bounced off the landing mats into the mud but continued to the harder surface beyond.

Thinking about it recently, my IA told me that I was lucky not to break something, because as he put it, "the steps are just glued on". But in my ignorance, I did it anyway, nothing broke, and the extrication was successful. I also think powering it off as I did was not the best way--probably better to have towed it off with one of the vehicles and a strap. Ignorance is bliss!

Cary

Those engine hoists are cheap, I got mine on Craigslist for $100 and use a 1" continuous strap to grab the gear leg. I think you can find them new for less then $300. The 2 ton limit might be a stretch for every day use, but for picking up one side of a 180 they are plenty sturdy. They are also on wheels so when your gear leg tucks under when lifting the hoist moves with it. They will also pick the tail up high enough to do a weight & balance. They are also much safer than a hydrolic jack setting on the floor. I know, that's a lot of also's.

Similar thread going on at sc.org right now

http://www.supercub.org/forum/showthrea ... Cessna-180

Nice to see all the different ideas. I use a tapered jack pad myself. I put a piece of rubber in between to prevent scuffing of the paint on the gear leg. I also use a large C clamp to hold the jack pad securely to the gear leg and prevent it from tipping off.