As a former parachutist who broke his ankle — to the point where my foot ended-up facing the wrong way — I can attest to the fact that one faces an imminent threat of grievous bodily harm or death when falling through the sky.
But unless you’re James Bond, you don’t need to be armed while in flight, and probably not even then! But if you are, you probably don’t need a silenced firearm. But if you do need one or just want one — ‘Merica! — it should have a lanyard loop. Just saying.