Just a quick q
I recently got back from holiday and I noticed an odd sound after touchdown.
The sound began after braking and reverse thrust when we were at a steady 20knots approaching the terminal.
The sound persisted even when the aircraft was stationary.
The sound was almost hydraulic and sounded as if a massive drill was on coming from beneath the fusilage. (It also fluctuated in frequency and pitch occasionally once parked)
I was postioned over the wing on an airbus A321
I don’t know if it was the auxilry power unit kicking in but doubt it.
Look forward to your response to a very Vaughn question.
No worries if no one knows it is a bit difficult to surprise.