It's not only limited manuverability, is the time window to see something that small and react at that speed. In an airliner at 180kts is like 5-7 seconds, you

It's not only limited manuverability, is the time window to see something that small and react at that speed. In an airliner at 180kts is like 5-7 seconds, you see a bird, confirm that is in a collision path and you correct you trajectory. At 400kts it's maybe 2-3 seconds to do all that. You need to be looking forward to have time enough, but you need to look elsewhere sometimes(instruments, to the sides, etc..). So it's possible to crash with something you didn't see comming if it's small.