C17's Igiload script had caused this problem when the mission already has the same script:
i.imgur.com / oZCgZm9.jpg (soory, I can't write URL today.)
It was shit.
PS:I confirmed the same bug appears on recently version(not only C17, it happens on the all of vehicles).
i.imgur.com / 5MZK8E0.jpg
I think to contain Igiload script directly is very bad idea.
It needs custom for compatibility.