That engine noise when an A320 takes off...

[RHPrague]

I've been meaning to ask this for years...

When I'm on an A320 taking off and climbing there's a loud and persistent whine on top of what I'd call "normal" engine noise, but I guess the whine is normal as I hear it often. It disappears as the plane levels off a bit after the initial steep climb. I took a BA 320 back from LHR on Sunday night, it was loud. On the outbound service, a 319, I hardly noticed it . What is it? Is it a characteristic of an older 320 version, or a certain engine?

Thanks in advance!

[ChrisJ800]

Older engines can whine loud. Newer engines have geared turbofans and are quieter.

[justapax]

Originally Posted by RHPrague

I've been meaning to ask this for years...

When I'm on an A320 taking off and climbing there's a loud and persistent whine on top of what I'd call "normal" engine noise, but I guess the whine is normal as I hear it often. It disappears as the plane levels off a bit after the initial steep climb. I took a BA 320 back from LHR on Sunday night, it was loud. On the outbound service, a 319, I hardly noticed it . What is it? Is it a characteristic of an older 320 version, or a certain engine?

Thanks in advance!

The A320 family has been through quite a lot of engines, look then up on Wikipedia, both ceo and neo had more than one choice of engine. I think you'd almost need to know the tail number of the aircraft you were on to tell which engine you were flying with.

These days, aircraft manufacturers tend to specify one or at the most two engine manufacturers for each airframe, for ease of maintenance and commonality of spares. Back in the 1990s, airlines could pretty much mix-and-match the engines to go on their airframe. Almost all engines apart from the RR Trent (which doesn't feature on the A320 family) are two-spool designs and should sound roughly alike. So your whistling engines need a cleverer head than mine.

[PAXboy]

That engine whine is noticeable and I have always presumed it is simply the engine working at it's upper thrust levels. As you say, it falls off rapidly once initial climb is achieved. Hopefully someone from the pointy end will be along soon.

[TURIN]

Originally Posted by ChrisJ800

Older engines can whine loud. Newer engines have geared turbofans and are quieter.

On the A320 series the only geared fan is the PW1100 GTF. BA did not opt for that engine, on the NEO they use the CFM LEAP.
To answer the OP, if you mean the lawnmower type sound, that is usually the sonic 'booms' from the fan blades. The blade tips are supersonic at high power settings.

[Mr Mac]

I always notice a vacuum cleaner like sound on the Airbus when they pass over when about 20 miles out from Manchester when they fly over us at home. I assume flap adjustment as I haven't noticed it much on board, and it only last around 5-10 sec. Any ideas ?
Cheers
Mr Mac

[TURIN]

Originally Posted by Mr Mac

I always notice a vacuum cleaner like sound on the Airbus when they pass over when about 20 miles out from Manchester when they fly over us at home. I assume flap adjustment as I haven't noticed it much on board, and it only last around 5-10 sec. Any ideas ?
Cheers
Mr Mac

Bleed valves scheduling?

[RHPrague]

Yes I guess "lawnmower" sound is a good description

I have found the exact plane I was on on Sunday evening : G-EUUH; a 320- 232 (it says on FlightRadar 24- I only have the free version so I can't read how old the plane is or which engines it has). It is quite an unfortunate sound because to us non-techy types, it sounds strained, and says "old plane" even if in fact it may not be.

[TURIN]

Originally Posted by RHPrague

Yes I guess "lawnmower" sound is a good description

I have found the exact plane I was on on Sunday evening : G-EUUH; a 320- 232 (it says on FlightRadar 24- I only have the free version so I can't read how old the plane is or which engines it has). It is quite an unfortunate sound because to us non-techy types, it sounds strained, and says "old plane" even if in fact it may not be.

IAE V2500. Yes it's an older type but there still hundreds still in operation.

[RHPrague]

I can well believe that, I was on a Volotea 320 last year that was really bad (but of course fine once it reached a decent altitude)

[tdracer]

Originally Posted by TURIN

To answer the OP, if you mean the lawnmower type sound, that is usually the sonic 'booms' from the fan blades. The blade tips are supersonic at high power settings.

We've always referred to it as "buzzsaw" noise, but yes it can be compared to a lawnmower. As Turin notes, it's due to the fan blade tips going supersonic during takeoff. Most pronounced in the front of the aircraft when you have a direct line of sight to the fan. The inlet acoustic treatment is designed to attenuate that noise, but if there is a direct path to your ear, the acoustic treatment can't help much.

[Uplinker]

Originally Posted by Mr Mac

I always notice a vacuum cleaner like sound on the Airbus when they pass over when about 20 miles out from Manchester when they fly over us at home. I assume flap adjustment as I haven't noticed it much on board, and it only last around 5-10 sec. Any ideas ?
Cheers
Mr Mac

Speed brakes deploying at high speed. I sometimes hear it in the London area - (and sometimes caused it !)

A bit like the BAe 146 flap howl, and a similar cause.