As you have noticed, when you eject from a fixed wing aircraft in Arma 3, you just appear near the jet with the parachute like you are doing HALO....
This is so wrong, and I can say why! When your jet is on low altitude its impossible to eject and survive!!!
You should be ejected with the seat, which shoots out of the jet upwards (usually with help of a black powder charge or an inbuilt reaction engine), making it enough altitude for a safe parachute landing!
I can assure you, the guy who ejected in this video is alive and completely unharmed.
also, don't forget that canopy should also shoot off completely!