Thanks 601, I haven't done a Part D for long time. However, if the inserted part is not objected to during the currency of the particular FOI's oversight of the AOC, then some level of approval is implied and therefore useful in a legal defence especially if pax videos indicate the aircraft was operated in compliance. You're right about the lack of FOI consistency, although some of it can be constructive if the later one(s) want to add requirements that make sense.
CAR 217 ? Looking at the time marks on our posts, I changed CAR217 (I used the wrong number) to CAR219 at right about the same time as you hit your 'Reply' button !
I'd be interested to see if the accident operator had a Part D to go with the pilot's Low Level approval.