I might be misunderstanding the purpose of "roll delay" property of of flights, but here is my impression.
I set up a route that is basically just a taxi pattern.
I assign two flights to that route.
On the second flight, I add a 60 sec "roll delay" in it's properties.
Expected behavior: I expected the first flight to begin taxi immediately, and the second flight to hold in place for the duration of it's "roll delay" and then begin taxi itself.
Observed behavior: the second flight immediately fell in behind the first flight and did not delay rolling.
Note: If I moved the second flight to a different route, it would sit on the tarmac and wait for it's roll delay before...well, rolling. So it seems any flight of a route rolling, cancels others flights of that route's roll delay?
Note2: in air spawn, the second roll delay flight still spawns immediately, just with it's position moved back the roll delay amount of distance. I guess that is not quite as weird, but it would have been better if it had not spawned for the roll delay period.
Note3: For that matter, in the taxi case, I'd probably prefer it not to have spawned until it's delay was over and it was ready to roll, so you don't have tons of planes piled up on the tarmac waiting.
(See attached sample mission.)
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CptTrips
