Lincoln From United States of America, joined Nov 2004, 3887 posts, RR: 8 Posted (3 years 8 months 6 days 3 hours ago) and read 2739 times:
Hey all,
Flying back from MSP last night on an ERJ-145 in 12A, which is my normal seat on the 145.
Shortly after we started the roll I noticed a nosie that could best be descrbed as an alarm clock (beeep --- beeep --- beeep --- beeep ---) that transitioned to a slow whoooooop (like an old-school fire alarm) that persisted until just after the wheels left the ground.
The flight was uneventful, and aside from passing by an NW aircraft that was closer to the aircraft than I've seen before (but appeared to be holding short) nothing else caught my attention. Pavement was wet; and the "beeping" didn't change speed as the aircraft accellerated)
Ovbiously whatever it was wasn't important -- but I've never noticed those noises before so I'm curious whatpart of the aircraft would be generating them.
Lincoln
CO Is My Airline of Choice || Baggage Claim is an airline's last chance to disappoint a customer || Next flts in profile
FLY2HMO From , joined Dec 1969, posts, RR: Reply 1, posted (3 years 8 months 5 days 23 hours ago) and read 2710 times:
Quoting Lincoln (Thread starter):
Shortly after we started the roll I noticed a nosie that could best be descrbed as an alarm clock (beeep --- beeep --- beeep --- beeep ---) that transitioned to a slow whoooooop (like an old-school fire alarm) that persisted until just after the wheels left the ground.
Where were you sitting? The only thing remotely close to that I've heard in the jungle jets that sounds like beeping is the top strobe flash unit. It's about 3 rows ahead of the wing exits. But it is really really faint and you really have to know what your looking for. I'm sure I was the only one that noticed it in the whole plane as it sounds exactly like the flash unit in a PA44.
At least I don't feel like an idiot for asking the question -- it was anything but faint; my first thought was that someone had a alarm clock going off in their luggage.
Lincoln
CO Is My Airline of Choice || Baggage Claim is an airline's last chance to disappoint a customer || Next flts in profile
Stratoduck From United States of America, joined Nov 2008, 25 posts, RR: 0 Reply 3, posted (3 years 8 months 3 days 2 hours ago) and read 2454 times:
The 145 begins pressurizing on take-off. Often the emergency windows will have a low pitched hum transitioning to a high pitched tone on the roll. It often ends just after lift off as the seals finally set.