It would be nice to have a landing gear counterpart to compliment the below commands:

isEngineOn
isCollisionLightOn
isLightOn

Would be nice also have:

isLandingGearOn

Why:

When using setPos on an aircraft, say a plane, if the landing gear is not down then that will affect whether I want put it on the runway or leave it as is.

For respawn scripts, I also use setPos to reset the vehicle rather than delete it and spawn a new one. Often when helicopters are abandoned in the field, they are with landing gear retracted. I want to know if they are retracted before resetting the vehicle, sort of like this:

if (isEngineOn _v) then {_v engineOn FALSE;};
if !(isLandingGearOn <vehicle>) then {<vehicle> landingGearOn TRUE;};
<vehicle> setPos spawnPos;

If I don't re-deploy the landing gear on reset, then it spawns with its belly on the ground is not good aesthetics.