Questions tagged [noise]
Questions related to aviation sound noise or regulations thereof.
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Can supersonic booms intensify as you fly longer?
If someone is flying just above Mach 1 for 10 minutes, I would think the sound/shock waves would just pile up and gain more energy, resulting in a very intense and loud boom when the pilot slows down.
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PA28 Archer 2 Circa 1986 - Noisy Engine
100 hours ago, a group-owned PA28 Archer II Circa 1986, 180hp plane had its engine rebuilt after 2500 hours. There had been no problems with the aircraft during the 2500 hours.
Since the rebuild, the ...
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Is it possible to identify plane engines by sound alone?
Can airplane engines be differentiated and identified by what noises they make? If so, what does each engine sound like? How would you be able to tell between a low-bypass and high-bypass turbofan? ...
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What is this noise?
In this video of a C42 landing, there is an audible, intermittent buzzing noise that persists until landing, at the 59 second mark, it reaches its loudest peak.
What is the noise? It's not a stall ...
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What causes subtle cyclical changes in engine volume at cruise?
A few years back, while trying to snooze on a Jet2 flight up at cruising altitude, my semi-attention wandered to the droning of the engine. I realised there was a very subtle effect of its intensity ...
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Is it true Wynantskill, NY has a real problem with aircraft noise from Air Force, or other aircrafts? Thank you
Is it true Wynantskill, NY has a real problem with aircraft noise from Air Force, or other aircraft? Looking to buy a home, but do not want this problem I may have heard on NPR. Thank you.
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What are the differences, if any, between aviation custom earplug and regular custom sleeping or musician earplugs?
I see some websites selling aviation custom earplugs. What are the differences, if any, between aviation custom earplugs and regular custom sleeping or custom musician earplugs (i.e., flat-response ...
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Buzz-saw noise from big turbofans at high thrust
This topic has been addressed many times on this and other forums. I have seen (and often not fully understood) some deep technical analyses, incuding manufacturers' research labs, since this is a ...
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Why do fighter jets make a whistling noise when landing and taking off?
Lately, I was watching fighter jets (F-16s and F-35s) from very close (fascinating!) and heard for the first time the "whistling noise" when they were landing and taking off. I expect it has ...
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A very loud, short- lived howl
Within the last eighteen months, I'd say - commercial aircraft descending into Heathrow have started to emit a terrifying, short-lived but very loud whining howl when they pass over my house. They are ...
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At what altitude can the sonic boom no longer be heard at sea level?
As others have stated here, you can hear the sonic boom of planes flying by at a fairly high altitude, ~80 000 ft. At what altitude would the sonic boom no longer be noticable at sea level? To add to ...
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UK noise certificate for below 9000kg?
This is regarding UK regulation - The Air Navigation (Noise Certification) Order 1990. I am curious what is the reason of specify this particular upper weight limit here:
"every propeller driven ...
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What is this sound on a B737-800 Takeoff?
Does anyone know what this sound is at 12:56 on a B737-800 takeoff?
The aircraft is N822SY, the airport is Denver Intl. Airport, and the runway is 34L.
Thanks and have a great day!
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Why are jet engines still so noisy?
In general, jet engines on passenger aircraft make so much noise that in a long-duration flight it becomes really tiresome and uncomfortable. Nowadays, technology is much more advanced than before. ...
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Does any of the hearing protection worn by aviation professionals use active noise reduction?
I have read that passive hearing protection (standard earmuffs/plugs) offer good protection against higher frequency noise but do not protect as well at lower frequencies. Supposedly active noise ...
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Why do some Airbus jetliners at full thrust sound like turboprops? [duplicate]
When riding an A3xx I always noticed the unique "turboprop" like sound when close to full throttle. Why is that so?
user57306
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Why do flying wires hum louder in a sideslip?
Page 50 of the Feb. 2021 issue of the EAA's magazine Sport Aviation reports that
Like any good vintage airplane, the Sea Bird likes to fly coordinated,
and the flying wires will sing out loud if the
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Whenever I hear a plane throttling down quickly, what is happening visually?
I am completely blind and have heard this several times when I was at air shows. Then my friend sent me this recording of a crop duster spraying the fields, and I heard the same type of sound.
It ...
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Why would changes in jet-engine power settings not result in changes in engine loudness?
My casual AAR reading has dredged up another counterintuitive detail of aircraft behaviour, this time regarding the relationship between engine power and engine loudness:
1.16.7.3 Sound Similar to ...
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Odd whining sound from planes passing over [duplicate]
I'm trying to figure out what is causing the sounds that I'm hearing from planes passing over my house. I'm located approximately 60 miles NW of ATL. The noise I hear sounds like a turbine rapidly ...
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What causes the horn-like noise during the start-up of some jet engines?
Here's the specific sound I'm talking about (it starts specifically 56 seconds into the video, as well as at 2:02 for the second engine):
I've only really heard that ...
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Do thrust reversers make more noise than engine at same RPM?
I'm talking about general aviation jet engines here. I live near an airport and I rarely listen engine noise on takeoff but always hear one during landing.
Would a jet engine at the same RPM make more ...
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What could explain the fact that during 1976-80, I used to hear commercial jets make sonic booms while flying overhead?
I've read on this site & on Wikipedia that there have only been a couple of commercial jet planes in history that have broken the sound barrier--either in testing (without passengers) or during an ...
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F-16: MAIN PWR ticking sound, what is it?
What is that sound that starts when MAIN PWR switch is turned on in the F-16? Its sorta like a fast ticking sound.
Why is it there, what makes it, when does it stop? And is it also there when only ...
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How to reduce the noise of the supersonic passage(bang)?
as you know the transonic phase is often associate with the bang.
The principal cons of the transonic phase is the noise,it's why there is not supersonic passenger aircraft( cause the end of the ...
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What's the rattling noise on an A320?
I recently flew on an A320, and during takeoff when the aircraft was rotating, I heard a loud rattling noise. If I had to guess I would say it came from the gear below but I can't be sure. I was ...
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Could propellers benefit from the design of the Blue Edge rotor?
Source: wired.com
If indeed the Blue Edge blades reduce noise by 50%, could the similar design be used on [forward-facing] propellers without a penalty in speed or agility?
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Could a shrouded fan blade with long chord length be efficient?
I am wondering if it would work to have a fan with two or three blades which have short-ish span and very long chord length, like half a rotation for each blade. Would a shroud (that is molded on the ...
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What’s that weird sound during spool up on some aircraft?
Some engines seem to make this characteristic “wailing” noise when spooling up. A good example of such is from 0:50 to 0:54 in the following video:
. I’ve also heard ...
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Is an afterburner louder than the same jet engine without it?
I would speculate that an afterburner increases the noise because it is nearer to the exhaust. But it certainly causes so many changes in the exhaust flow that it could be less loud as well. It may ...
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Will you be able to hear a supersonic aircraft flying away from you?
I'm wondering if you could be able to hear the sound emitted by an aircraft say traveling at Mach 2 away from you.
I wondered if it might shift the emitted frequencies beyond the audible range. Would ...
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Why are the first sounds of an approaching enroute airliner low frequency, booming ones?
Often I will hear an intermittent, low frequency, powerful, booming sound that resolves into that of an airliner flying enroute high (FL 300+) overhead. So the first sounds that an airliner flying ...
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Why is a Lockheed MC-130J Commando II creating such a loud droning sound?
Today I heard a loud droning sound which is really unusual in the area of west London I live in; so I went on ADS-B exchange and it showed a USAF Lockheed MC-130J Commando II flying literally right ...
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How does the noise of a 2-to-4-seat helicopter compare with that of a similarly-sized fixed-wing aircraft?
We are considering allowing helicopters on our private airstrip (2600 ft strip). Noise on the ground (and approach) is the concern from the community.
Does anyone know approximate dB ratings for a ...
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What is the loud noise of a helicopter when the rotors are not yet moving?
What is the loud noise when a helicopter is ready to start flying, but the rotor is not yet rotating?
For example at Trump's "chopper talk", when he is intercepted by reporters on the way to Marine ...
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Why don't modern jet engines use forced exhaust mixing?
Jet engines are noisy[citation needed] - even a modern high-bypass turbofan is still deafeningly loud compared to pretty much anything except the even-louder low-bypass turbofans or a turbojet (much ...
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Is ear protection necessary for General Aviation aircraft?
What would happen if someone flew a brand new Cessna Skylane/Caravan or a Robinson R22 without using earplugs or headphones? Would they get hearing damage or it would be just a little bit loud where ...
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What is the cabin noise hertz in typical commercial aircrafts?
In cabin, we hear noises in commercial aircrafts. Wondering if it is in general over or under 100 hz. There should be a band width. Thanks!
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Can ADS-B used for voice communications?
Everyone knows the radio communications doesnt sound great altough they work perfectly.
But can the brand new ADS-B communications be used for carrying audio signal? Would it be clearer?
The ADS-B ...
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What kind of microphones does aviation use?
Do they use the dynamic ones or cheap ribbon ones? Also why are these microphones so small?
I guess they dont use condensers. (I am yet to see an 3.5mm jack (which is used both on the C172 and the ...
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What causes the sudden spool-up sound from an F-16 when enabling afterburner?
What causes the sudden spool-up sound from an F-16 when enabling afterburner?
I've included a video to make it clear what sound I'm referring to:
at 1:16, I assume ...
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What causes the nose landing gear knocking noise on a Boeing 777 while taxiing?
The NLG knocking noise heard on taxi-in to stand, what could cause this knocking noise?
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Can helicopter rotor produce infrasound?
While watching a Mil Mi-17 helicopter takeoff I experienced strange thing. The helicopter produces a lot of noise even when just starting the engines.
But shortly before taking off the high-pitched ...
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What's the mechanical 'whoosh, whoosh' sound in this video?
Sound in question comes right after the warning sound at 22:57.
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Why are the cabin chimes one semitone lower on the Boeing 747-400 than on other aircraft? [closed]
I noticed that the cabin chimes on the Boeing 747-400 overall sound one semitone lower than on other aircraft, including the 737, 777, Airbus A320, and even the 747-8. The same semitone-lower chimes ...
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What are the unique sounds emitted by Embraer E190-E2 on final?
I live close to an airport where these aircraft frequently land. When the E2 is between 2-3 thousand feet, something which I can only describe as whale moans, is heard.
I say they are unique because ...
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Why would a turboprop rev down just before going full throttle during takeoff?
The only turbprop I've travelled is the ATR 72. I've noticed that the props' rev go down (for like a second, the sound also goes down) just before engaging full throttle in order to takeoff. I've ...
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In terms of noise, how does a steep climb-out compare to a noise abatement procedure?
For airports in populated areas, it is common to implement noise abatement procedures. In practice, this means that aircraft reduce thrust on departure, so that noise is reduced in proximity to the ...
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Are there any reported cases of noise from helicopters causing damage to property?
In the Netherlands, three cases have been reported of Chinook helicopters' rattle noise (low frequency sound) damaging solar panels. The Dutch defense ministry recognises this problem and the lawyer ...
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Is there any way to reduce the noise and vibration in a C-130 Hercules?
We are using C-130 B and E Models with T-56 A-15 engines and Hamilton Sundstrand 54H60-91/117 propellers. A lot of vibration and resonance are felt on these military version aircraft even after using ...
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