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Old 12th Jun 2015, 01:44
  #17 (permalink)  
JammedStab
 
Join Date: Apr 2008
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Originally Posted by Capt Quentin McHale View Post
JammedStab,


From my experience that noise you're hearing in the flightdeck and on the maindeck below could be a dried out nose gear steering collar "groaning" during turns. Engineers tell me they usually give the collar a good lube and problem noise disappears. Also, one would think that sitting in the flightdeck with engines running, you would be too far away from the body gears to hear any noise emanating from them unless maybe a severe structural failure that I would guess you would feel through the airframe as well.
Actually, I am not so sure about that based on two examples I experienced. In the first one we were at max takeoff weight holding in position on the runway for a few minutes. I was just in the observers seat. While in position there was a continuous creaking noise in the cockpit although not as loud as is frequently heard in the turns. An experienced captain said that it was likely the body gear steering being not quite centered but trying to become centered. But that could be incorrect.

The other day we had the body gear steering inop. In this case, the taxiing it was only a slight bit more difficult for the turn even shallow 90 degree turns but when a sharp 90 degree turn was made, a lot of that creaking noise was heard(more than normal) and was felt through the tiller.

Nose and body gear both on the same hydraulic system.
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