GNAV question
Hi guys,
I'm sitting over this question and cannot find my mistake. Maybe I can't see the forest through the trees.
Given: TAS 120kt
ATA at A: 12:32 UTC
ETA at B: 12:47 UTC
ATA at C: 12:50 UTC
ETA at D: ?
(Distance A to B = 30 NM; Distance C to D = 20NM)
One could say, easy: 20NM/120kt = 10', ETA at D is 13:00 UTC but this answer is marked wrong.
I was thinking that at B it's only an estimate, so I figured maybe we're flying slower or faster.
Actual time at A 12:32, actual at C 12:50, flight time of 18'.
distance: 30NM + x
V: 120 +- y
When I use the TAS of 120NM, the distance between B and C is 6NM and t=0,05 (3') and everything checks out. But the answer of 13:00 UTC is still wrong.
I'm grateful for any hint.