Cockpit Wind Noise

[natedog74]

Drivers with experience on both bus and boeing: which is quieter? Any big differences on different types in the two fleets (OG/NG - 737/777, 300/340.…)? Other birds -MD’s, etc…..
Traceable to windshield alone? Noise levels while operating wipers…

[alexban]

I can tell you this : NG is a lot noisier in the cockpit than the 3/4/5 series of 737. This is mostly due to air conditioning ,especially from the air used for equipment cooling,I suppose.
You can't hear any difference when you shut down your engines on a NG :)
Noise from wipers ? The NG is better than the classic,due to a specially coated window.
:ok:

[safetypee]

Hawker 125 variants have differences. Pre -800 used flat windscreens, the centre and side screens top corner joins and the side screen top corner to fuselage joint both result in a noisy vortexes along the side of the flight deck. The 125-800 and later variants use curved screens and are much quieter.

[HotDog]

The quietest cockpit I've ever been in is the DC10.

[Taking Over, Nigel]

Not surprisingly faster = noisier.
747 is noisier than 767. (M 0.85 vs 0.79)
777 is noisier than 767 (M 0.84 vs 0.790) same nose!
737NG is noisier than 737 classic (M 0.78 vs 0.74) same nose.

The 747 would be noisier still if it were not for the beautifully curved windscreen.- glad I don't have to try to make that glass!
Have flown all of the above and none are really that noisy except low level high speed cruise.
However all ARE noisy enough to give long term hearing loss hence the noise cancelling head sets many airlines now use.

[747FOCAL]

All,

alexban- It has impact but next to the air running over the fuselage I doubt the AC is what you are hearing.

The noise in the cockpit is mostly due to the air slamming it's way up the front of the aircraft. The 747 has a huge noise problem due to the rapid accent of the air up the nose that drops down like a hammer on the upper fuselage. This occurs on all aircraft, but varies depending on aircraft type.

There are things that could be done and people are working on them.

The scary part is that if we made a perfectly "air noise" quiet flightdeck you guys would hear all the other clicking and etc noise that is below the ambient(due to wind noise) noise floor.

You have to understand, quieting a noise is only part of "noise reduction". As soon as you quiet one, another rears it's ugly head that was buried under the noise of the first and you couldn't "hear" it. Hence why most manufacturers are attacking turbo machinery noise on aircraft as that is the new frontier.

:ok: :)

[m&v]

The B727 on descent would set up quite an increase in slipstream noise over the windshield,especially at M83/390.
Older model A320 had noisy A/cond.....
Cheers:D

[square leg]

The MD11 is also very quiet, probably similar to the DC10.

The EMB145 is a noisy buggar at high speed. During climb and slow flight it seems to be acceptable.

[ArcticTurn]

alexban,

I agree, the NG 737 is much noisier than the 300/500. Almost as noisy as a -200. I find if youturn off the recirc fan at the gate you can at least hear yourself think. And yes the new intermittent wipers are much quieter. I think even a Trabant had quieter wipers than the old 73's. It only took 30yrs for Boeing to figure that one out. Now if they would just put the cabin temp controls in the cabin....can't hear the chime from the cold/hot FA due to the noise in the cockpit! :ok:

AT

[natedog74]

taking over, nigel:
where did you hear/read about the long term hearing loss from wind noise alone? or is it just ambient noise (engines,etc) in general? any web/pprune links? as for the noise-canceling headsets - surely on turboprops, but on heavies? replacing the one-ear itty-bitty headphone with a bulky pair of mufflers? any specific airline, headset brand? for the hearing loss, any numbers/length of time? one would imagine that whatever the damage after, say, 20 yrs on the job, it would still be within the less-strict/commensurate with age hearing loss criteria for medical...

[Taking Over, Nigel]

natedog74
Occupational Health & Safety studies have proven that ambient noise level (ie: a combination of everything) on the flight deck of most if not all large (jet) transports is enough to cause permanent hearing loss- over many thousands of hours. We are not talking about astronomically high noise levels here, but we are talking long time frames.
Sure, there are far noiser workplaces, but the fact remains.
As a result, many airlines are moving to noise cancelling headsets- various brands, with a recommendation/requirement to wear them ears covered in cruise. Most I think (including ours) wear them one ear ie: inboard ear uncovered during approach/ departure phases of flight to make communication easier.
Some pilots hate'em- I like them now I'm used to them.
By the way, we are talking lightweight "Active Noise Cancelling" NOT the bulky passive ones I wore many moons ago in turbo-props(back in the 70's).
Hope this helps

[Ignition Override]

Taking Over N: You mean airlines actually pay for those noise-cancelling headsets? Or is it required by a pilot contract? :suspect:

[FlyinWithoutWings]

Taking Over- What brand of Light Weight Active Noise Cancelling headsets are you using?

Thanx :ok:

[Pilocol]

All you guys are so lucky.
I have to share Cockpit with an F/O that I think is already deaf … the pane I fly is very quiet, but the F/O is so loud, I have to turn vol. Down when he speaks… leaving me with no vol. To hear ATC…
:(
Pilocol...