Engine(?) Noise 737-300QC
Was on a flight (as SLF) recently on a 737-300 seated just aft of the wing (seat 16A I think) and noticed an usual noise in the cabin (on both the outbound and return journey a week later) that I assume is "normal" but having never heard before piqued my curiosity about what it is.
I know there are probably literally hundreds of possible causes of this - but figured it might be something common that has an easy explanation :p
On the ground as the engines were started and we were pushed back there was a repeated (4 or 5 times followed by a pause and then repetition) "clunking" (for want of a better word) which was accompanied by a vibration that could be easily felt through the floor. This continued until the engines had spun up a bit. The same noise was present after landing as we approached the stand.
I was on the same a/c for four different take offs and landings in the space of a week and it did this each time, yet other 737s I've travelled on haven't (or at least I've been unaware of it)
I'll add that I was travelling with a nervous passenger who immediately asked me in a panicked tone "what's that" to which I obviously replied ... "oh, it's normal on this type of plane" to reassure them ... ;)
(on an entirely unrelated note this flight ended with the announcement "Cabin Crew - Doors to automatic and cross-check" which concerned me more and hoped all the pax would be treated to a demonstration of how the slide deployed and generally make disembarking rather a lot more entertaining ... alas they did what they were supposed to as opposed to what they were told to ;))