I noticed an odd sound coming from the engines of the CO 738 and 752 that I was on going to and from PVR, respectively.
Right after takeoff, a noise that could only be described as similar to a lawn mower began in the engines, and it did not quit until we were at crusing altitude. Could anyone explain to me what it is that I was hearing? I noticed this noise to be especially prominent when we flew on B6 last year, but I heard it for the first time on CO in April.
Thanks for the info!