Vertical axle travel vs increase weight

[franc11]

Hi,

I'm looking at the loads on a MLG obtained with a simulation software. The aircraft I'm studying has has a weight increase. So for the same landing cases, we have an increase in drag load ans in vertical reaction. So I was wondering if the vertical axle travel should increase or decrease under those increased loads?

Thanks

 

[rb1957]

you need the gear (and tire) stiffness curves from the OEM, but then how did your simulation work without this data ? maybe you're looking at static cases ...

alternatively you Might be able to measure the gear (ground test). probably you'll need a scrap gear if you're applying ultimate loads.

then there are all sorts of questions about the gear structure itself, but then i guess these are questions for another day ...

 

[franc11]

Basically, you mean that it depends on the gear and tire stiffness and it might increase or it might also decrease?

Because, the thing is that I have results of the simulation and it gives me lower VAT for the increase weight on gear of the aircraft. I was just wondering if that could be correct or obviously wrong.

 

[rb1957]

i think that's a pretty odd conclusion. sure gears can have funny valving inside them, controlling the gear's response to load; but i think spring curves should be monotonic ... increasing the load should increase the defelection (tho' maybe by a decreasing amount, ie non-linear).

also if you're increasing the load on a tire remember to check the tire pressure, you'll probably need to increase it (which'll make it stiffer ...)