Landing Gear reliability testing.

[nomorevishnu]

Hello,

I was wondering what kind of reliability tests I could do with landing gears. The one we are working with, is a conventional, trail dragger. Right now, we are building a model and later on the full size.

But we are focusing on reliability and I'd like to know good methods so that I can test it with the scale model and compare it and probably use the same for the big model too.

I was thinking about running a Finite Element Analysis in some CAD program, but is there any real world stuff that I could do other than simulation. The model we are building right now is a 9 pound plane.

Thank You,

vishnu

 

[nomorevishnu]

Someone? Please.

Is my question vague? Do I have to be more specific here?

 

[ank_gl]

I don't actually know how it is done, but I saw an episode on discovery showing the testing of main landing gears. It was an obvious drop down test for the bogie(with some force i guess). And for the wheels, the wheels were dropped(not dropped actually, but lowered), on some rolls to test the wheels.

Of course, you can make separate parts and check for the stresses knowing the forces(you can calculate forces i guess, a rough idea atleast, simple mechanics!)

One question I need to ask. We know that impact loading makes the induced stress twice of the value obtained in gradual loading(or any other factor, maybe 3 times the stress for gradual loading). So am I safe enough in simulating a static structural problem with twice the stress rather than going for dynamic analysis??

 

[brewnog]

Carry out a design FMEA, then have a look at the failure modes needing some test work.

 

[FredGarvin]

Carry out a design FMEA, then have a look at the failure modes needing some test work.

You mean act like an engineer? Huh. Who'd a thunk it?

You will also need to look into applicable Federal standards in whatever part of the world you are in that govern flight safety and aircraft certification.

 

[brewnog]

You mean act like an engineer? Huh. Who'd a thunk it?

Yep, I've been fully institutionalised. Does it show?

 

[FredGarvin]

Does it show?

Oh yeah. You have been assimilated. Welcome to the collective.

 

[Thefirm]

I use aluminum spring main gear on my taildragger. Max weight at 1650 lbs...For lighter projects, design your own, do some drop testing.

 

[Danger]

Is this gear retractable? If so, there are a lot more potential failure points that you need to address.
I took your term 'conventional' to mean fixed, but one mustn't assume.

 

[Thefirm]

It is fixed. In aviation, conventional gear usually means opposite of tricycle...

 

[Danger]

Actually, I was a pilot many moons ago. (Hence my signature. ) A lot of taildraggers have retractable mains, though, which is why I asked for clarification.

 

[Thefirm]

No kidding? I have flown quite a lot over 22 years but only in a few models... and I have seen only one taildragger that had retractable mains...that was a 182RG. What are the other models?