Thanks for the precise report this is an old bug. Will be fixed for next patch.
What was happening was the order of testing.
step 1 update and move your plane.
step 2 measure distance to drone and explode if needed.
step 3 update and move the drones.
Hence any very long frame , I.E. like when you come back from an Alt tab. Could make your plane to fly over 1k yards in 1 frame and hence the drone would explode before they were moved on the same frame.
It shows up more frequently with the 29 simply because it flies faster.
HiTech