UsAirways16bwi From United States of America, joined May 2004, 1003 posts, RR: 4 Posted (7 years 8 months 1 week 4 days 19 hours ago) and read 2946 times:
Everytime I fly on a 757, there is a loud bump just as the plane lifts off the ground...it sounds like its coming from the main gear, or somewhere underneath the plane. Anyone know what it is?
320tech From Turks and Caicos Islands, joined May 2004, 487 posts, RR: 5 Reply 2, posted (7 years 8 months 1 week 4 days 19 hours ago) and read 2940 times:
Not having had the privilege of having flown on a 757, I can only surmise that it's the bogies dropping into the retraction position (ie, leading wheels up).
The primary function of the design engineer is to make things difficult for the manufacturer and impossible for the AME.
MX757 From United States of America, joined Aug 2005, 602 posts, RR: 12 Reply 3, posted (7 years 8 months 1 week 4 days 18 hours ago) and read 2936 times:
After rotation the main gear shock struts go to full extend. And the forward part the truck-the front axle with the front wheels on it- tilts up. That could be the "bump" you are hearing.
Dl757md From United States of America, joined May 2004, 1555 posts, RR: 18 Reply 5, posted (7 years 8 months 1 week 4 days 4 hours ago) and read 2793 times:
I concur with the explanations above. The truck tilt actuator has 3000psi hydraulic fluid acting on it and it pretty severly rams the truck to it's tilt position against the stops. When the truck hits those stops that hard it's going to make a pretty loud thump. No problems though as they where designed for this.
TinPusher007 From United States of America, joined Feb 2005, 963 posts, RR: 2 Reply 8, posted (7 years 8 months 1 week 3 days 4 hours ago) and read 2625 times:
Quoting GARPD (Reply 7): I'm generaly more tuned into listening to the fabulous sound of the RB211s on take off power.... ooo baby
I concur....but I also love the sound of those bogeys slamming into place after rotation...sounds powerful.
"Flying isn't inherently dangerous...but very unforgiving of carelessness, incapacity or neglect."
KhenleyDIA From Sweden, joined Feb 2005, 409 posts, RR: 0 Reply 9, posted (7 years 8 months 4 days 6 hours ago) and read 2410 times:
From what I have noticed, if you listen for it, you will hear that on most major commercial airplanes. Maybe I should say, anything larger then a 737 or A320.
KhenleyDIA
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