Why is there so much noise on passenger jets during flight?

[stoned]

what are all that noises on passenger jets when flying with full load of passengers ? I thought it going to be really quiet on board but there is so much noise that one can't hardly sleep on board.

 

[FredGarvin]

Ummm...wind noise, passenger noise, engine noise...Can you be a bit more specific? Can you describe the noise a bit?

Smaller aircraft tend to be a bit louder because they can not separate the cabin from the engines as effectively as would be hoped. Also, the smaller the aircraft is weight becomes more of a dictator in what can be added to the structure. To help keep weight down, noise proofing is kept to a minimum.

 

[stoned]

with like 200+ people on board all the machinery required to keep air fresh etc. must make a lot of noise, I wonder how quiet is if i were the only passenger on let's say airbus a 340?

 

[Danger]

Almost all of my flying experience was in small manually operated planes. The few times that I was in Airbuses or L1011's several years ago, I was amazed by how much control-surface actuator vibration is transferred through the structure. I could feel the flaps dropping into place through the seat. I always tried to sit just behind the wing, though, so that I could watch things working. Maybe it doesn't travel much farther than that.
It still beats the first commercial plane that I was in—a Vickers Viscount. There was about 1mm of free play in the rivets, so we could see the wing plates hopping up and down. I've since been told that it's a deliberate design feature involving stress relief, but I can't help thinking that it must cause some seriously accelerated metal fatigue. Fred?

 

[Francis M]

with like 200+ people on board all the machinery required to keep air fresh etc. must make a lot of noise, I wonder how quiet is if i were the only passenger on let's say airbus a 340?

It would most likely be the same.

 

[FredGarvin]

Almost all of my flying experience was in small manually operated planes. The few times that I was in Airbuses or L1011's several years ago, I was amazed by how much control-surface actuator vibration is transferred through the structure. I could feel the flaps dropping into place through the seat. I always tried to sit just behind the wing, though, so that I could watch things working. Maybe it doesn't travel much farther than that.
It still beats the first commercial plane that I was in—a Vickers Viscount. There was about 1mm of free play in the rivets, so we could see the wing plates hopping up and down. I've since been told that it's a deliberate design feature involving stress relief, but I can't help thinking that it must cause some seriously accelerated metal fatigue. Fred?

The Viscount?? Holly molley are you dating yourself there Danger! I can't honestly say that I had ever heard that, especially on wing panels. The aero guys would have conniption fits over something like that. I'll have to research that one and get bak to you.

 

[Danger]

The Viscount?? Holly molley are you dating yourself there Danger!

It was in '66, the first summer after moving to Ontario. We were coming back to Calgary for vacation, and the Windsor airport couldn't handle jets at that time. We had to rattle our way to Winnipeg before transferring to a DC9. That was the first time that I'd been in a plane and, believe it or not, it just reinforced my desire to be a pilot. (Probably based upon some perverse desire to inflict that same physical hardship upon other people myself. )