Airbus A320 pilots??

[Tupac]

Don't make me Coombz you. 

The noise is the hydraulic Power Transfer Unit, like cpxxx said.

Ripsnort works for Boeing, so he is biased.

[phatzo]

Ripsnort works for Boeing, so he is biased.

He's the chief airbus fault designer.

[nrshida]

Ripsnort works for Boeing, so he is biased.

 

[Orbitson]

yeah, i remember hearing it, looking out the window to see the flaps at 5, not moving, and thinking "man, that's weird"

Exactly my experience.  The noise lasted at least two minutes and the guy across the aisle looked at me with a wtf face and I'm sure I had the same look.  I offered my fuel pumping theory and all was good.  Next time I'll have the correct HPTU answer. 

  Thanks to all for the input

[nrshida]

The real reason for the noise is to weedle out the Boeing fans by their frightened faces so they get the cold coffee 

[MrRiplEy[H]]

Had a nice RT..as a passenger ..DTW>JAX this week. On the outbound climb out heard an unusual/scary sound I would associate with flap deployment/retraction but flaps were in cruise position already.  I'm guessing they were pumping fuel between tanks.   

The Avro RJ-85 sounds also freaky by default. When it 'goes clean' the windflow on the flaps/slats makes a loud howling noise during retraction. Same thing happens in reverse on landing. It was a bit unnerving on the first time I experienced it - I haven't seen this happen on any other plane model.

[Golfer]

"What noise? I didn't hear anything."

[Tracerfi]

Snakes?

Snakes on the Plane
 

[rogwar]

There is a A320 that fly's above us every 2 saturdays.  It's Malaysa air.  Beautiful aircraft.

I doubt it's an A320 from Malaysia all the way to Southern California.

[flight17]

I doubt it's an A320 from Malaysia all the way to Southern California.

Lol, was thinking same thing when I read that last night... But was gonna let it slip...

[Dago]

I happen to know the A320 quite well, including the systems operations.  You won't hear them transferring fuel between tanks in flight, as this cannot be done.  Fuel can be fed from any tank to either engine, but this is not audible.

The Hydraulic system does have a PTU that can transfer pressure (or energy if you will) between two of the hydraulic systems, but this isn't typically heard in normal flight as it requires difference in pressure that is larger than normally occurs with both engines running at or above idle.  It can happen though.  On the A318-A321 series aircraft you can often hear the PTU loudest during engine shutdown/spool down when the pilot kills the engines in a staggered manner.  If he kills them simultaneously it isn't always heard.  When it is heard, it makes a sound that is often compared to a barking dog, declining in frequency and volume as the engines slow to a stop.

Could you have heard the speed brakes being extended?

[Babalonian]

I doubt it's an A320 from Malaysia all the way to Southern California.

Via Tokyo, duh.   They fly from KLIA to LAX with a stop there to gas up and of/on load passengers only going for one leg.

[flight17]

I doubt it's an A320 from Malaysia all the way to Southern California.

Via Tokyo, duh.   They fly from KLIA to LAX with a stop there to gas up and of/on load passengers only going for one leg.

Then again, sun country flew their 737-800s from MSP to Europe a couple of times a few years ago and a few other North American carriers send A320s across the pond. I know air Canada has flights from Newfoundland Direct to Europe on their A320 or A319 and I want to say delta has done the same through the NE US but I can't say that for sure. I swear I have seen pics of the delta birds doing this, but maybe not.

[rogwar]

Via Tokyo, duh.  They fly from KLIA to LAX with a stop there to gas up and of/on load passengers only going for one leg.

Went to Malaysia Airlines site and looked up the flight to LAX.

It's a Boeing 777-200.

 

[Vulcan]

I happen to know the A320 quite well, including the systems operations.  You won't hear them transferring fuel between tanks in flight, as this cannot be done.  Fuel can be fed from any tank to either engine, but this is not audible.

The Hydraulic system does have a PTU that can transfer pressure (or energy if you will) between two of the hydraulic systems, but this isn't typically heard in normal flight as it requires difference in pressure that is larger than normally occurs with both engines running at or above idle.  It can happen though.  On the A318-A321 series aircraft you can often hear the PTU loudest during engine shutdown/spool down when the pilot kills the engines in a staggered manner.  If he kills them simultaneously it isn't always heard.  When it is heard, it makes a sound that is often compared to a barking dog, declining in frequency and volume as the engines slow to a stop.

Could you have heard the speed brakes being extended?

None of the above, I hear it all the time. It sort of sounds like a car starter motor turning over with a flat battery, except it repeats for about a minute.