Questions tagged [noise-reduction]
Questions about reducing the impact of aircraft noise, either by reducing the amount of noise generated, changing aircraft flightpaths so that more of the noise is generated farther away from anyone who might complain, or both.
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What type of engine sound suppressors are used in general aviation?
Today we were discussing about noise pollution and why aircraft engines considered one of the biggest contributors to producing high intensity sound and I thought are there any ways and/or methods ...
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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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How would flying into Frankfurt a.M. Airport be problematic for the Tu-154?
A friend of the family lives in the approach path of Frankfurt a.M. Airport (FRA, EDDF). Until a few years ago, Tupolev Tu-154s were still flying to this airport, although as I understand, they don't ...
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What were the rules about night flights from LHR in the 80s?
I was just reading a question over on movies.SE: How could Ryan land in New York in early morning?, and the accepted answer suggests that Jack Ryan's plane takes off from LHR at about 4am.
One of the ...
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How did the Blackops 'quiet one' helicopter muffler work?
Back in the Vietnam War era, special ops needed a quiet means of inserting soldiers behind enemy lines to install eavesdropping equipment. They modified a Hughes 500 to do the job. One of the things ...
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The principle in 'Trompe' is applied to airplanes?
'Trompe' (see Wikipedia) is a water-powered air compressor, commonly used before the advent of the electric-powered compressor. A trompe is somewhat like an airlift pump working in reverse, used to ...
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Is engine sync to avoid beat frequencies also a concern for jet engines?
Is synchronization of rpm to avoid beat frequencies also a concern on jet engine aircraft like it is on propeller driven airplanes?
Context:
This question on SE-Aviation discusses prop sync for ...
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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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How does the X-59 achieve low-noise supersonic flight?
By what mechanism or combination of mechanisms does the X-59 reduce the noise produced by its sonic boom? What are the design choices that led to this outcome? I really want to understand the issue ...
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Using ANR aviation headset with a PC
I just started my studies towards PPL, and am looking into buying a good ANR aviation headset for flying on Cessna 172.
I have an office job, and I'm dealing with a lot of noise, hence ideally I'd ...
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How (and when) does Heathrow alternate arrival paths?
I've noticed that flights over Richmond (particularly arrivals) seem to have significantly reduced over the last few weeks. This is based on looking at Flightradar, as well as listening to the noise ...
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Aerospike nose cones for supersonic jets?
Not to be confused with aerospike nozzles. This is about the big pin-like rod in front of ICBM nose cones.
This answer (from Space) about aerospike nose cones notes that one of the potential ...
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Why does Schiphol airport have such a long taxi way? [duplicate]
I heard that from runway 18R-36L the taxi time is around 20 minutes, I heard that this runway was built and is used mainly to reduce noise pollution, but what reasons are there for the length of the ...
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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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What are ways to reduce drag and noise generated by the landing gear?
Apart from using fairings, what ways are there, or have been studied, but not necessarily implemented in reducing drag and noise produced by the landing gear, mainly for commercial aircraft with ...
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Do noise abatement procedures have an impact on aircraft emissions?
The ICAO has imposed Noise Abatement Departure Procedures (NADP1 and NADP2) in order to limit the noise impact of departing aircraft on communities living nearby airports. Could noise reduction lead ...
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Is hypersonic flight possible with a Busemann's Biplane?
The modifications to the Busemann's Biplane design reported in this article have proven that it is possible to design a modified Busemann's Biplane wing design that actually produces lift at ...
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What noise reduction measures were taken in the time between hush kits and chevrons?
In older jets such as 727 hush kits are used in the engines to reduce noise. In very modern jets such as 787 or 747-8F, chevrons are used for the same purpose. What happened in between? The switch to ...
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Which type of chevrons is applied on the B787?
Which type of chevron nozzle was applied on the B787? I'm really confused about whether if it's sawtooth or sine wave.
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Why are light aircraft engines so noisy?
I live near an airport where students spend a lot of time flying circuits. During the base leg, pilots can be heard reducing engine revs prior to the final left/right turn to line up with the runway.
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In what way(s) will making an airplane electric help to make it "quiet"?
In this blog I read about the Quiet Flight Initiative, which - if I understand correctly - will be quieter than a comparable carbon fueled plane at least in part because it is electric. It's an ...
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What factors come into play when reducing the total noise generated by a helicopter?
I simply cannot understand how a helicopter can be made quieter. What are the things that would considerably affect the noise signature of a helicopter ?
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Can quadcopter-like UAVs ever get significantly quieter? Any candidate technology?
note: this question is old (2016) but so far remains unanswered. Perhaps innovations have improved on the noise even since this was first posted.
The light weight quadcopter and hexacopter UAVs that ...
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What are the relative internal noise levels in various aircraft?
What are the relative noise levels in various aviation scenarios for observers seated inside an aircraft? I'm sure the specifics depend on model but I'm curious if any general trends can be drawn that ...
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Can noise from contra-rotating propellers be reduced by having a different number of blades on each propeller?
Heads up: This came from Wikipedia's page on contra-rotating propellers and it explicitly says citation needed:
However they can be very noisy ... It is also helpful if the two propellers have a ...
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Which UK airport uses different approaches for noise reduction?
I remember hearing about a British airport that had two approaches that were used on alternating weeks. They implemented this pilot project (no pun intended) so that different houses would be ...
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