Theory On Engine noise

[Voyager]

I was writing a huge post on a theory that the real reason WWII pilots couldn't hear anything outside the plane was that airspeed generates white noise, rather than it being the engine noise from the aircraft, when it just hit me, the pilots are all wearing earmuffs!

New theory: pilots can't hear anything outside their planes most of all because they are all wearing headsets, which combine earmuffs, with speakers. The speakers you can hear, and anything outside the earmuffs, you can't. The expection are things that have a path of solid matter to you. Your engine, is attached to the frame, which is attached to your chair, which is (one hopes) attached to you. It sounds a bit like the Boots of Water Breathing, but it does work.

I can't believe that never occurred to me until just now. It's only been what, eight years?

Harry Voyager

[brando]

One of the first things that happened to me after I bought IL2 Sturmovik was my wife bringing back a flying helmet that she'd found on a shopping expedition somewhere. Oddly enough it is exactly the type shown on the box for that first version of IL2, with the padded bar across the crown and a hefty pair of bakelite headphones concealed in the protruding earpieces. Once strapped on it becomes difficult to hear much, and it would be even more isolating when the phones are plugged into an active R/T system.
I don't think it would prevent anyone from hearing the massive noise of an aero-engine mounted a few feet in front of the cockpit - but it would muffle and distort much of it. It would also be nothing like the sound experienced by people on the ground, with the added Doppler effects thrown in.

Back in the distant past, before motorcycle crash helmets were mandatory, it was common to take a ride bare-headed in order to listen to the subtleties of the engine noise when trying to tune it. With a helmet on it was impossible to hear nuances like chainlash or tappet rattle. Nowadays, with full-face helmets it is often more likely to be wind rush that is the major sound.

So I agree that the perceived sound from within a flying helmet is rather different from that heard with the naked ear.

B

[JZG_Pedro]

I'm a RL pilot, PPL, on my final hours for CPL. Of course, I don't fly 1500 - 2000hp 3- 4ton props; rather 160hp 700kg ones :P lol


We use the headsets with ear cuffs, probably with slightly less noise reduction than WWII ones. Dude, still with a 10x less powerful engine, it's A HELL LOT OF NOISE! If you take the headset off, the noise is unbearable. Also, if I speed up (silly thing, from 100 to 150 mph ) the wind whistles quite well, you can hear a little "clanking" when lowering flaps too. I always imagine what it would sound like to fire guns from that plane. I've never heard anything bigger than an 8mm rifle, firing 3m from me, and I'm sure it would be heard in a plane (less loud, but still), specially the repeating mechanism of an automatic gun.

[brando]

Hello cousin Pedro - long time since we flew FB together mate! I'm glad to hear the CPL is going well :)

I didn't mean to suggest that the helmet would blot out the sound of the engine, far from it; more I was thinking that it would alter the ability to hear the various components and turn it into a continuous roaring sound.
I've just been reading pilot accounts of flying Hurricanes in the Battle of France and it's interesting to note the general comment on the sound of the gunfire when the button was pressed to unleash the 8 303's in the wings. All of them describe it a "crashing" sound, completely unlike the "taka taka taka" of popular fiction. Maybe it's because the latter is what gunfire sounds like from outside that it's often described that way.
Another popular comment was that sound also tied in very closely with what was being felt by the body due to vibrations through the airframe. One described "two bloody enormous explosions" behind him, combined with massive jolting sensations. He looked behind him, expecting to see that the back of the aircraft had disappeared, but it hadn't and he recovered and dived out to land across the Channel. Once down, inspection showed that the plane had taken two cannon hits only - one having hit a fuselage former and the other the armour plate behind his head! It's interesting to note that two cannon hits don't necessarily constitute a kill.

B

[proton45]

I read something just recently where a pilot make a comment about what you could hear in combat, and he said (something like)..."if you can hear their guns they are too close".

[AA_Absolute]

In IL2 now and always some people can hear other planes engines at kilometers :( as "sonic radar"

One of the big unsolved bugs in il2.

[rakinroll]

In IL2 now and always some people can hear other planes engines at kilometers :( as "sonic radar"

One of the big unsolved bugs in il2.

How possible is it? :eek:

[AA_Absolute]

As Oleg say:

"2. In Il-2 the sound engine was designed for HiEnd sound cards. It was so different sounding on Hi End and on regular cards.... On simple motherboard cards of some producers the panning was so simple, that we was unable to control it or regulate the distance... and some people begun to use it... In BoB we will have completely new sound engine that will not depending of type of sound card. We simply did own panning code, etc..."

If you like use this exploit google SoundExt.occlusions=0 or attenuation=0, afaik lots of squads know how to use, but dont like say to all community as logreaders etc.etc

PD. I hate exploits and dont use it

[JZG_Pedro]

Howdy Brando! Long time indeed, Im looking forward to fly a little more with you guys.

Surething, I wasnt meant to contradict you in my post, it was more towards Voyager, to share an experience =)


Interesting stuff you wrote. Ive read similar things too, pilots often talking about guns sound feeling close to the vib. in your body.


*!*

farewell, m8!

[proton45]

How possible is it? :eek:

I thought this had to do with the "attenuation" setting in the config file?

[Voyager]

Howdy Brando! Long time indeed, Im looking forward to fly a little more with you guys.

Surething, I wasnt meant to contradict you in my post, it was more towards Voyager, to share an experience =)


Interesting stuff you wrote. Ive read similar things too, pilots often talking about guns sound feeling close to the vib. in your body.


*!*

farewell, m8!

I had a hearing test a few months back, and apparently one of the tests for hearing damage uses a headset with a hard plastic foot instead of one of the phones, that they place on the back of your head, hard against the bone. It uses bone conduction, instead of the air conduction for the side with the hard foot, and if you can hear the hard foot better than you could with the speaker, that indicates one type of hearing loss.

So, even with ear protection, you're going to hear the vibration sounds, even if you don't hear the gas driven sounds. You'll get the banging of 12 cylinders and their assorted valves, but you won't necessarily hear the howl of the exhaust.

Now I suddenly wonder if pilots were hearing the firing of nearby rounds, or if they just hear the sonic booms as the rounds went past? I recall something about early investigations into the speed of sound being started by some infantryman wondering why misses cracked twice. Then again, when we're talking about machineguns, how do you tell the difference between the 2nd crack, and the 2nd shot?

Harry Voyager