Author Topic: Profile landing gear location (Read 841 times)

jim gilmore · « **on:** March 17, 2009, 11:54:06 PM »

I'm building a shark 402 and replacing the single gear with a 2 wheel set-up. Is there any reason that I cannot drill a hole further towards the front and slant the wire for the gear aft as long as the axel comes out far enough forward of the c/g ?

Dick Fowler · « **Reply #1 on:** March 18, 2009, 11:01:47 AM »

Seems to me it should work. I would consider using pretty stiff wire. The backward angle will create a spring effect that could drive you nuts on the landings.

james dean · « **Reply #2 on:** March 18, 2009, 01:17:53 PM »

Jim,

I just don't think this could work. For starters, the wire gear would be acting like a leaf spring in this position and angle. Issues like propeller tips sawed off, bouncing landings and take offs come to mind.

OH, the thought of it!

Sorry to be harsh, I beg your pardon. The gear legs need to be at or near right angles to the ground when mounted in the profile arrangement to better take advantage of the quality's of the piano wire. Your mounts for the wire gear should be about 1 1/2 in.s forward of the CG on a profile of average dimensions.

The way the plane touches down during landings will be affected by the positioning of the gear on the fuse'. The farther forward from the CG it is the more bounce you will get and more difficult to keep the plane on the ground after touchdown. (lots of bouncing around) You get the multiple landing syndrome with out the proper positioning of the gear legs.

I have a profile 52' Nobler that has this issue of "Multiple landing syndrome) in great part to the positioning of the gear on the fuse'. (Well, maybe the piloting skills play a part too)

But hey , this is about the gear!!

Another thing to consider is how much of the flying you will be doing over grass. The gear placement would be a little farther forward (About 1/2 in. )than if flying over hard deck.

Hope this helps.

James Dean

Mark Scarborough · « **Reply #3 on:** March 18, 2009, 01:27:33 PM »

My step daughter and I are building a pair of shark 402s, ( her first real building project,, wo hoo)
I understand your desire to use a two gear setup, however I have lots of planes that have the single gear and they work GREAT even when flying off a stooge. so if you insist, sure use two wheels, but there will be a weight penalty, however this may or may not be an issue, just make sure you use light wheels, no heavy old RC wheels or the vertical CG will be off.
NOw next point, is there some reason you want to move the landing gear attach point forward? As for the location of the wheels, Pat is pretty well in tune with this, and I would make sure the wheels end up where they are shown on the plans, how the wire gets to the wheels, well pays your money and takes your chances,, Personally, I would mount the gear the way shown, I think you will be happier in the long run unless there is some specific reason for doing otherwise. Dont think you would need to move the hole in the fuse even if you do go with two wheels.

Author Topic: Profile landing gear location (Read 841 times)

jim gilmore

Profile landing gear location

Dick Fowler

Re: Profile landing gear location

james dean

Re: Profile landing gear location

Mark Scarborough

Re: Profile landing gear location