Cue the Forrest Gump accent. I got my shiny new leeaggs yesterday. Finally the Landing Gear Works (aka Tom Anderson) has jumped through all the hoops and secured his STC/PMA from the FAA... and the new Ti gear legs are shippable. Now to block the airplane up and take the old ones off.... any ideas?

gunny

He was advertising them (or at least there was talk about them) several years ago. They're just now getting PMA approval? Wow, the wheels of progress at the FAA do grind slowly...
I would use an engine hoist or overhead hoist (like a chainfall) latched onto the engine mount (NOT the engine's lifting eye) to get the front of the airplane off the ground. Secure the tail to help keep the airplane from swinging around.

Gunny wrote:Cue the Forrest Gump accent. I got my shiny new leeaggs yesterday. Finally the Landing Gear Works (aka Tom Anderson) has jumped through all the hoops and secured his STC/PMA from the FAA... and the new Ti gear legs are shippable. Now to block the airplane up and take the old ones off.... any ideas?

gunny

We're talking about N748P, right? Looking at your pics, you've got seaplane lifting rings... What am I missing?

Mike-

Well, what you are missing is that I'm doing it my hangar at my house... and the ceiling is only 12'/sheetrock. I've got a crane that would use the seaplane rings easy peasy... but too large for my hangar. It will take about a week or more to do... gotta send the brackets back to TLGW to be shaved. The issue with engine hoits is weight/arm.... to lift 1500lb or more you need a short arm. I have to use my hangar so I'm in a bit of a bind... all I need is about 4".... maybe I can make an engine hoist work.

gunny

And yes the FAA wheels grind slowly... I've had these on order/paid for for over a year. Happy to have them now!

gunny

How much weight change?

edit - I looked it up -- 26# lighter for the pair

I'd find a hangar elsewhere that I could properly lift the plane. I've seen some $$$$ damage done to these things by jury rigged lifting setups. Even if you have to rent space for a week, it's cheaper than big repair bill.

It's possible to safely lift from base of engine mount, but risky. That's a lot of weight to put on that tubing.

MTV

+1

Gump

Why not rent/borrow some wing jack from you IA? I'm much rather have a plane resting on some jacks under the wings than hanging from the engine mount.

This is why I'm putting lifting eyes on my Bearhawk wing attach points. (not that that helps you.)

whee wrote:Why not rent/borrow some wing jack from you IA? I'm much rather have a plane resting on some jacks under the wings than hanging from the engine mount.

Unfortunately Cessna high wings don't have jack points under the wings.

That being said a friend of mine has a 185 that somebody (MAF?) did fabricate and install jack points for just outside the strut attach on main spars, very stable when on jacks. Not sure what sort of approval/engineering was done.

gotta send the brackets back to TLGW to be shaved.

Why not just get new brackets from P ponk and do whatever needs to be modified and then install one side at a time using the engine hoist with a strap around the engine mount close to the firewall and a jack under the gearbox. That way it is supported two places and just one side at a time.

Gunny

Don't feel too bad. It took me a 18 months just to get a new set of steel 180 legs for my 170.
That I used to own.
The big problem at that time was that I ordered mine in the middle of a 'domestic' squabble, and he had a hard time finding anyone who could properly heat treat them.

I had a fantasy about putting them on my 170 but not at the price of $11,000 at the time.
Question: If he used to sell them - why is it that they are just now approved? What am I missing other than some old memory cells?, and my 170.

I hope that you have already done the P-Ponk gear box upgrade if it does not come with the new legs
The P-Ponk gear box upgrade is one of the better investments.

Seems to me that I have seen Cessnas on stilts out at the upper strut attach point when the local shop did gear cycles for the retractables at annual time..

Good luck

Chris C

Gunny,

Having done this recently, I can share how I did it in my T-Hangar. The good news is, if you have everything set up in advance with all the parts/hardware/tools ready to go, the actual time on jacks (or hanging) can be minimized to an hour or so. Bolting them in is pretty strait forward, but most time will be spent setting the wedges. There's really no way to know what you will need for the shim thickness until you have the legs bolted in. But getting to the point...


I fabbed some "jack pads" out of sheet alum and a wooden block that attaches to the wing just outside the lift struts, centered on the main spar. Just take the screws out of the inspection plate, and screw in the jack pad using the inspection cover holes. This secures the pad to the wing and assures correct alignment under the main spar. It's best to have the tail elevated to have the wings as level as possible (chord wise), to avoid any potential stresses on the jack pads bolted to the wing...I used a 55gal drum which raised it 3-1/2 feet or so. DONT FORGET to weight the tail down, the CofG is forward of the main spar when unloaded.

I purchased two high lift jacks from "Harbor Freight Aircraft Supply" that had a telescoping pad. ($69 apiece). I originally thought to use these after lifting the plane with a forklift from the engine mount, but realized later that there was enough travel in the jacks to get the tires off the ground by themselves. I could go on about the intricacies involved in this process, but suffice it to say, "think things through carefully". I'll just include some pics

This pic was taken afterward so the tail isn't raised, so you can see the incorrect geometry...


The jack pad. The wooden block is screwed to the alum, and there is padding on the underside to protect the paint...


Another angle...


In a precarious position...

I cobbled up a wooden cradle to fit well to bottom under gearbox, leaving access to the spring bolts. Lifted it with a hydraulic machine shop table on casters. Was very stable. Plane sat on it for months.

I think a motorcycle lift would would work, too. Block it if stops don't fit the height.

The cradle is two 2x10 (or 2x8) stringers, bandsawed to fit the shape. Rear stringer is shorter to account for the slope. Screwed blocks between for stablity. Topped with masonite and two layers of carpet. I cee-clamped it to table.
Did not take long to make. (Don't forget bolt access)

No photos. I passed it on to someone, if I find it I will get a photo.
Call if I can answer question five three zero
two one niner 0664
--Bill

Chris-

Apparently that domestic squabble forced him to totally redo the STC's and PMA's. Therefore the extreme wait. Hoops jumped through now though.

gunny

Bill-

I was thinking along these lines... but hard to find a hydraulic table around here.

thanks,
gunny

All-

I agree that the plonk mods are a good thing... they are already installed. I can't do one at a time because the brackets have to go back to TLGW to be shaved... I could do that myself, but I'd rather have a machine shop do that work.

I like Bart's version of jackpads..... seems more stable and less prone to some of the problems I envision. I appreciate all of ya'll's inputs! I'll keep you posted.

gunny

Gunny, just curious. Does metal get shaved on both upper and lower surfaces or just the bottom side of brackets opposite where the shims go? How much thicker is your new leg vs. what you're taking out?

Gunny wrote:Cue the Forrest Gump accent.

Hey! Don't be makin' fun of my accent!

Gump