Nauseating aircraft vibration...on the ground

[ivymike]

I am, for the moment anyway, stuck in a large airplane on a taxiway ar ORD. We will be returning to a gate shortly because of a mechanical problem that the pilot is not comfortable with. In the meantime, the plane is shaking arrythmically in a most nauseating fashion. It seemed to get worse at one point when the engines changed load. Probably 15 more minutes of this to endure. There are dogs barking downstairs...

Anyway, I can only imagine that strong winds might be to blame, but out the window I can see no indication that this is the case. The lawn grass isn't moving, but I can't see much else. Any other theories?

 

[ivymike]

Couldn't resist telling the lady next to me that it was probably a bad dog gear.

 

[SomptingGuy]

Dog sucked into compressor?

- Steve

 

[MikeHalloran]

A pilot friend of mine who flies propjet twins for commuter airlines related a similar story, sort of.

He complained about one of his two engines vibrating to a degree that shook the entire airframe, frightened the passengers, and made even the aircrew nervous.

The mechanics fixed it, in about 15 minutes, by pumping half a barrel of grease into the propeller hub.

To his surprise, it stayed fixed.




Mike Halloran
Pembroke Pines, FL, USA

 

[ivymike]

We're taxiing now.. The shaking is pretty silly at this point..higher frequency and amplitude. Ugh.

 

[ivymike]

We just made a right turn and the vibes briefly stopped. How odd.

 

[ivymike]

Smooth as can be with the engines off.

 

[VEBill]

It's probably caused by someone (!) failing to turn off their smartphone. ;-)

 

[patprimmer]

It's probably just a few blades missing of the turbine.

Regards
Pat
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[msquared48]

Or one of the engines fell off.

Mike McCann
MMC Engineering

 

[KENAT]

Nah, that'd be a single 'thump'.

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[msquared48]

OK, then it was more than one...

Mike McCann
MMC Engineering

 

[vpl]

Not an entire engine falling off, just a single blade coming loose.

Ivymike, glad this was found before you got into the air.

Patricia Lougheed

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[BigInch]

Did I tune into Twitter?

We will design everything from now on using only S.I. units ... except for the pipe diameter. Unk. British engineer

 

[btrueblood]

Lemme guess, Airbus product?

 

[ivymike]

it was a Boeing 757. once they determined that we weren't leaving, they gave us permission to turn the phones back on.

The plane eventually left (5hrs late) but I wasn't there for it.. thanks to a lucky conversation with a woman in uniform, I was one of four people who slipped into another plane within minutes of getting off the broken one, and made it home only a couple of hours late.

 

[SomptingGuy]

Not Airbus then. Probably some antiquated us crap.

- Steve

 

[johnhors]

"Lemme guess, Airbus product?" - if it had been an Airbus product then the engines would have been CFM , which are 50% US anyway!

Boeing 757 only uses Rolls-Royce engines - a UK product !

Boeing or Airbus, they are international products and have been that way for many many years! I have worked for one aerospace company in the UK for 30+ years and in that time we have supplied and continue to supply both Boeing and Airbus.

So putting one down in favour of another makes no sense wth respect to national boundaries.

http://www.Roshaz.com

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[stevenal]

Please turn off and stow all electronic devices.

 

[btrueblood]

Disagree, john. The one thing Boeing can do right is controls and dynamic response. Airbus planes have made me seasick more than once. The 340 had a noticeable, pronounced dutch roll that had me green (sitting in aft row seat). Much worse than the similar tail-wagging that the DC-10 does; that mode is just not noticeable on the 747 or 767. Boeing planes have (typically) stiffer flight modes, had engine autosynch before Douglas, ... list goes on. I will admit I'm talking about in-flight responses, not ground/taxiing responses, and if something is goofy with an engine, any plane can respond strangely. And newer jets from the other side of the pond are tighter/stiffer than the old ones, so they are coming along.

But putting them down is just as sensible (frankly more sensible) as rooting for your "home team" players, you know, the ones that traded in from your rival team.