L1011-500 oscillating question

[locky]

As you all know I am but just a flight attendant and DO NOT claim to know "diddly" about the functions of jet engines. I have been on one of our Lockheed 500 series planes for two trips in a row. I know the sounds and feel of our Lockheed's inside and out and I know when something is a miss. There is a feeling right after take off ( only on the second leg of the trip.. strange I know) it feels like the aircraft is shuddering. I called it a vibration. I question the first front end crew and tho they said they felt it they did nothing. The next crew was more helpful and discussed it in length. The 3 crew members affirmed my suspicions that there was a irregular feel. They called it an oscillation tho. There were no indicators in the cockpit at all. They have since "logged" it.. yet another F/a said the feeling is still there. Anyone care to speculate?

[Kermit 180]

That the drinks trolley is not anchored, thus moving the center of gravity when the aircraft is pitched.

Kermie

[locky]

On take off Kermit?? EVERYTHING is secure

[Tricky Woo]

Probably that old bloke in first class with Parkinsons Disease.

TW

[gravity victim]

Almost certainly it's the Guvnor, committing an act of furtive self-abuse under a blanket as he listens to the thrilling sound of a real L1011,and dreams his dreams of Celtic Wings... <img src="wink.gif" border="0">

[Tcas climb]

Could this be during slat and flap retraction?

[Kalium Chloride]

Not an ex-Eastern L-1011 is it? <img src="wink.gif" border="0">

[Boss Raptor]

used to be called 'pod nod' by Gulf Air crews I think...as I remember and it was a longtime ago...oscillation under certain atmospheric/flight conditions in the engine nacelle which causes side to side oscillation of the pods which translates to the nose going up and down...dont ask me why/what etc. that's all I remember!

[ipanema]

That slight wobbly feeling is very probably all those wheels spinning right after liftoff. It stops when the landing gear is retracted.

[locky]

interesting replies folks! <img src="wink.gif" border="0"> Tcasclimb.. simply.. NO.
Iknowthat these babies are dinosaurs, but this only happens on the one aircraft! we have several 500's and this is the only one doing this!

[polzin]

Keep reporting it !! If it is pod nod they might lube the fan blades. The engine actually oscillates in an orbit and usually vibrates the entire aircraft.

[Send Clowns]

Good to see the true principles of MCC (multi-crew co-operation) being applied. As we were told in our course, Locky, no-one is "just" an FA, they should all report anything they think might have safety implications!

[bblank]

no-one is "just" an FA

Yep, read the last chapter (the one before the epilogue) of Ernest K. Gann's "Fate is the Hunter."

[locky]

awwwwwwwwwwwwwww ta SC and Brian!
feeling important now!!! :/
I am the deicing watchdog 2!

[Willit Run]

As much as I hate to agree with the Polzin man, he is right, although a big dork, that is probably what it is, POD wobble. its not that unusual.

Love ya Kenny!

[411A]

Well locky, if you want to know, ask the L10 experts. Email is best.

[locky]

411A;
Could you lead me in the right direction to these Lockheed experts?
Thanks!

[Flapskew]

If it is pod nod, try reducing thrust, back to idle if necessary, and after a minute, increase thrust again. Might stop the nod cycle. <img src="wink.gif" border="0">

[Kermit 180]

Whoops, sorry Locky! Because this topic was originally posted in JB I thought it was a joke of some sort hence my useless reply. Pardon me.

Kermie <img src="redface.gif" border="0">

[Hot 'n' High]

Hiya All,

This thread may have solved a little riddle for me. Back in '86 I was SLF on a Cathay 1011 out of BK and I noticed a vibration through the early part of the climbout (say to 5000 ft or so). Never could work out what it was as it appeared not to be wheel/flap related. Never came across it again so just pondered on the matter ever since then. So, years on, PPRuNers have come to the rescue and solved something that has been bugging me. At last I can sleep at night!

Cheers, H 'n' H <img src="smile.gif" border="0">