When the player is in an FFV position that can stop being FFV (Co-pilot taking controls, Tank commander turning in), the reload that was started but not finished continues while the unit is no longer FFV-enabled.
- Legacy ID
- Firing from Vehicles
- Open editor, place yourself down as a Sniper (Has weapon with long reload time)
- Place an empty MH-9
- Launch mission, get in the MH-9 as Co-pilot
- Fire a bullet, then start reloading your sniper rifle than "Take controls" of the MH-9
- Observe that you can now start up the helicopter and pilot it, while the reloading your rifle is not interrupted
- Wait until the reload animation is complete, then "Release controls"
- Observe that the reload completed successfully as you have a fresh magazine loaded
Technically, we can argue that the tank commander resumes his reload inside the turret as he is invisible, but this just seems like a bug as there can be other positions with FFV which are not capable of doing so, like the MH-9 Co-pilot and are visible.
My suggestion is that the moment FFV is disabled, any reloads in progress are aborted.
To really drive the point home, as co-pilot start flying the helicopter, release controls, start reloading your rifle and take controls again.