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Landing gear

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fulcona

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Dec 20, 2004
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29
I'm about to weld onto my landing gear legs , the pads that the axles will bolt to. I will be setting toe-in/out and camber at this time. The plane is a taildragger. Should I have the plane in level flight attitude when I do this or should it be done with the tail on the ground? ( or somewhere in between.) Such a small percentage of flight will have the plane on its main gear and also at level flight attitude, I would think the 3 point attitude would be correct. Thoughts?

Neal
 

Andy_RR

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Sep 29, 2009
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248
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Melbourne, Australia
I'd have thought you'd want the best rolling efficiency during the high speed portion of the takeoff roll where you definitely will be only on the mains if you want it to be successful!
 

Dan Thomas

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Sep 17, 2008
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We always did them three-point. The toe-in/toe-out shouldn't change much between three-point and level attitudes, since that's only about a 12 degree rotation. You'd have to have a lot of (like way too much) camber to make a serious alignment issue with attitude changes.

The alignment needs to be done at or near typical operating weights. Hard to do if you're still building the airplane. Pad-mounted axles can use tapered shims for final settings once the airplane is completed.
 

Pops

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We always did them three-point. The toe-in/toe-out shouldn't change much between three-point and level attitudes, since that's only about a 12 degree rotation. You'd have to have a lot of (like way too much) camber to make a serious alignment issue with attitude changes.

The alignment needs to be done at or near typical operating weights. Hard to do if you're still building the airplane. Pad-mounted axles can use tapered shims for final settings once the airplane is completed.
The Bearhawks use a large adjustable rod end at the top of the shock strut to adjust for the average load of the airplane. The oil damped dia spring in the shock strut has a certain pre-load for the EW.
 

Dana

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Apr 3, 2007
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If the landing gear pivots are parallel to each other and perpendicular to the axles there should be no alignment change other than camber regardless of loading.

When I rebuilt the landing gear on my Starduster I had the plane hanging from a hoist. I tack welded the axles in place with a long tube slipped through the [hollow] axles to hold them in perfect alignment. Getting the camber right was a matter of getting the spring deflection right with weight on the gear, with fine adjustment with threaded rod ends on the bottom of the spring struts. I must have gotten it right because it tracked straight as an arrow.
 

Pops

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When building 4 Bearhawk fuselages, etc. Dallas Shell and I built this jig to keep the axles straight. Bolted the fuselage LG brackets to the gear legs and set the LG on the lower longerons and after getting everything straight welded the LG bracket to the lower longerons. The short angle piece on each end was as long as the box tubing, welded on, then cut the center out so both ends were straight with each other. Worked good on all 4 Bearhawks.
Bearhawk on gear. Another fuselage on table.

SSSC stored for the winter weather on its nose. Like the military used to stack the L-4 Cubs .
 

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