I decided to look for mods to find what fits the question.
There is somewhere a memory of a tiny helicopter I've seen on Arma 3 server, but I forgot how it was called. So I went to search through 40 pages of helicopter mods and show you what I can find.
Jetpack by riten
https://steamcommunity.com/sha…?id=766566053&searchtext=
Reason why I'm listing this mod as possibly fitting:
Jetpack has near zero survivability in case it gets shot at. Pilot is exposed, only his armor will protect him (and even that is doubtful).
Doubts:
It may be limited by server to have less than full tank on spawn to make a small 'hop' from one point to another.
If it can cross Altis sideways back and forth, that may be overpowered for a beginner, since it allows player to avoid conflicts with patrolling NPCs right from the start.
_________
WithesUmbrella
https://steamcommunity.com/sha…id=1695940281&searchtext=
Reason:
Same as jetpack. Full vulnerability of pilot.
Funny.
Doubts:
May have unlimited fuel / range and height of flight. May lead to player avoiding conflict with NPCs.
_________
Hot Air Balloon
https://steamcommunity.com/sha…?id=758179713&searchtext=
Reason:
Most people will crash. No armor.
Doubts:
No height limit mentioned in mod.
_________
FOUND IT!... Well, similar.
Ultralight Helicopter
https://steamcommunity.com/sha…id=1792515412&searchtext=
Reason:
No armor. Has chance to explode on landing.
Doubts:
No height limit, but very limited fuel.