tvh
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Noise of new generation aircraft.

Thu Nov 01, 2018 8:13 am

Schiphol is going to make a difference in landing fees depending on the noise categorie of the aircraft.
I think that is a wise thing to do.

see:
https://www.luchtvaartnieuws.nl/nieuws/ ... liegtuigen.
Dutch only.

From the article they have the following classes:
S1 747-200, MD-83.
S2 A300, A330, 767-300, 747-400
S3 A320, 737-800, 767-400, 777-300 and Embraer 170/190.
S4 757-200, 777-200
S5 Dash-8 en Embraer 145
S6 A321neo, A220, 747-8, 737 MAX 8
S7 A320neo, A350-900, A380, B787.

Never heard about these catogories, Strange that the A330 is doing so much worse than a B777-200. Also remarkeble that the A380 is doing beter than the much smaller A220. I think these classes need some tuning. What do you think ?
 
FlyingHollander
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 8:23 am

I saw the article too and share your thoughts. Really interested in how these classes were determined.
If it ain't Dutch, it ain't much.
 
Lufthansa
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 8:54 am

What was wrong with he old system?
I live on a flight path about 6 km from a major airport and I can tell you there's not much
difference unless you're REALLY close to the end of the runway between an A380, a 777 and
an A380 taking off. Throw the A330 into that mix too. What is even more odd is they seperate the A321NEO
and the A320NEO. This looks less about noise and more about the types they want to
service the airport.
 
M564038
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 9:02 am

1/Noise is complex.
2/Depending on how you set up your measurement you can get factory friendly results far, far away from
how people actually hear noise.
The A320 belongi g to a certain category might be as sinple as normally using a slightly highet trust setting, or a certain angle of attack giving a different airstream and thus noise curve.


I didn’t see anyone saying this list was from worse to better, the definition of the categories might very well be quite different.
 
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CARST
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 9:04 am

tvh wrote:
Never heard about these catogories, Strange that the A330 is doing so much worse than a B777-200. Also remarkeble that the A380 is doing beter than the much smaller A220. I think these classes need some tuning. What do you think ?


Considering this ain't some slapdash nation, but the Netherlands, I think there will be real, hard numbers behind these classes. There is a sound-profile for every airliners for multiple points on approach and departure and I'm sure they've made up that list with these numbers and sound profiles on hand.

Lufthansa wrote:
What was wrong with he old system?
I live on a flight path about 6 km from a major airport and I can tell you there's not much
difference unless you're REALLY close to the end of the runway between an A380, a 777 and
an A380 taking off. Throw the A330 into that mix too. What is even more odd is they seperate the A321NEO
and the A320NEO. This looks less about noise and more about the types they want to
service the airport.


The "old system" just doesn't take into consideration the noise an airliner makes for the people living under the approach and departure routes. It just is based and weight and size and sometimes the number of passengers.

Regarding A321 vs A320, the A321 is a stretch from the A320 and got a different flap system. It's very likely that this changed flap system for the larger A321 generates more noise than the standard A320 flap system. If that hasn't changed with the NEO, this could be the reason for the A321 getting a worse rating than the A320.
 
Lufthansa
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 9:22 am

*correct for about quote... it should have said A380, 777 and A330. Auto correct strikes again.
I guess I should learn to use my laptop rather than phone. But Interesting information about the flaps
on the 321. That would make sense. Part of the noise is air frame noise and how engine noise is deflected.

I'd be interested to know who still flies the 747-200 into AMS? All I could think of was government planes and
they're exempt from noise restrictions pretty much globally. Almost all cargo operators ditched more than a
decade ago. Plus no mention of any Russian types.
 
smartplane
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 10:20 am

tvh wrote:
Never heard about these catogories, Strange that the A330 is doing so much worse than a B777-200. Also remarkeble that the A380 is doing beter than the much smaller A220. I think these classes need some tuning. What do you think ?

Perhaps they are banding using noise profile divided by average seat numbers.

A number of countries / airports are proposing to take this one step further, and charge emission fees based on the aircraft / engine type, weighted by actual passenger numbers using CORSIA data / reporting.
 
PlymSpotter
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 11:44 am

I expect they've ranked the aircraft according to their EPNdB noise footprints - makes sense.

It's anecdotal, not scientific, but I do find the A330-200 to be disproportionately noisy. I currently live in a mobile home a few miles from LGW, on a slight hill and within clear sight of the airport, so there is nothing to block the noise. When the A330-200s depart (take off, not flyover) to China or other long haul destinations, things vibrate - if I have a cup of tea on the table, the surface will ripple slightly. The 777-200ER does have the same affect on longer flights, recently we had Thomas Cook and BA departing to CPT, almost one after the other, but I perceived the A330-200 to be slightly louder, despite being smaller.

Fortunately I'm not at all worried or bothered by the noise, and we're about to move back into our proper house post renovation, which will now be more insulated anyway.
...love is just a camouflage for what resembles rage again...
 
na
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 12:51 pm

Lufthansa wrote:
I'd be interested to know who still flies the 747-200 into AMS? All I could think of was government planes and
they're exempt from noise restrictions pretty much globally. Almost all cargo operators ditched more than a
decade ago. Plus no mention of any Russian types.


I think until 2 or 3 years ago Kalitta operated 742Fs into AMS. As for Russian planes, which ones are still operated into Western Europe? Havent seen any for years at least at FRA. I am one of those living near FRA who did profit from the flightpath changes of some years ago. No aircraft noise anymore except some smaller planes flying over my house, or the occasional 747(-8) freighter on an odd path. However due to my profession I am regularly at the airport and I judge those types/classes mentioned are correct. MD-80s have vanished, they were always the loudest here. From the big modern jets the 777s and 330s are loudest, A350s, A340s, A380s and 787s the quietest.
 
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Dutchy
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 1:04 pm

na wrote:
As for Russian planes, which ones are still operated into Western Europe?


According to this article in Dutch, Maastricht Aachen Airport is raising their landing fees for the Russian types: Antonov An-12, An-22, An-24, An-26 and An-30. This is due to complaints from their neighbors, thus they have landed there recently. Don't know the operator though. The tariffs are set at such a level that it is unprofitable to land with these machines at this airport.
Many happy landings, greetings from The Netherlands!
 
Rara
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 1:09 pm

smartplane wrote:
tvh wrote:
Never heard about these catogories, Strange that the A330 is doing so much worse than a B777-200. Also remarkeble that the A380 is doing beter than the much smaller A220. I think these classes need some tuning. What do you think ?

Perhaps they are banding using noise profile divided by average seat numbers.

A number of countries / airports are proposing to take this one step further, and charge emission fees based on the aircraft / engine type, weighted by actual passenger numbers using CORSIA data / reporting.


I would guess that seat numbers played a role. It does make sense from a resident's perspective - you would rather have the noise of one A380 than six A220s even if a single A220 is a little less loud.
Samson was a biblical tough guy, but his dad Samsonite was even more of a hard case.
 
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frigatebird
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 1:27 pm

tvh wrote:
Schiphol is going to make a difference in landing fees depending on the noise categorie of the aircraft.
I think that is a wise thing to do.

see:
https://www.luchtvaartnieuws.nl/nieuws/ ... liegtuigen.
Dutch only.

From the article they have the following classes:
S1 747-200, MD-83.
S2 A300, A330, 767-300, 747-400
S3 A320, 737-800, 767-400, 777-300 and Embraer 170/190.
S4 757-200, 777-200
S5 Dash-8 en Embraer 145
S6 A321neo, A220, 747-8, 737 MAX 8
S7 A320neo, A350-900, A380, B787.

Never heard about these catogories, Strange that the A330 is doing so much worse than a B777-200. Also remarkeble that the A380 is doing beter than the much smaller A220. I think these classes need some tuning. What do you think ?


Interesting indeed. Above aircraft types are examples mentioned in the article, there are more on the list of course (like the AN-124 I suspect, although it's a rare visitor). The article mentions it's not just noise, pollution is a factor too (CO2 emissions for example). This could explain why an A321 has to pay more than an A320, and a 77W more than a 77E. Funnily enough, the 764 is cheaper than the 763!).

Very interesting to see the 737 MAX8 is more expensive than the A320neo! This might be a factor in the KLM narrowbody fleet decision :duck: Or is just the P&W powered A320 in the cheapest category? For LEAP powered aircraft, I would think the 737 MAX would be quieter than the A320 due to the chevrons.

PlymSpotter wrote:
I expect they've ranked the aircraft according to their EPNdB noise footprints - makes sense.

It's anecdotal, not scientific, but I do find the A330-200 to be disproportionately noisy. I currently live in a mobile home a few miles from LGW, on a slight hill and within clear sight of the airport, so there is nothing to block the noise. When the A330-200s depart (take off, not flyover) to China or other long haul destinations, things vibrate - if I have a cup of tea on the table, the surface will ripple slightly. The 777-200ER does have the same affect on longer flights, recently we had Thomas Cook and BA departing to CPT, almost one after the other, but I perceived the A330-200 to be slightly louder, despite being smaller.

Fortunately I'm not at all worried or bothered by the noise, and we're about to move back into our proper house post renovation, which will now be more insulated anyway.


I too think the A330 and also the A343 (I've never witnessed an A345/6 take off) is noisier than expected. I guess it's just perception, I like the sound of a GE90 a lot better.
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Iemand91
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 1:54 pm

Lufthansa wrote:
I'd be interested to know who still flies the 747-200 into AMS? All I could think of was government planes and
they're exempt from noise restrictions pretty much globally. Almost all cargo operators ditched more than a
decade ago. Plus no mention of any Russian types.

No airline flies the 747-200 into AMS.
When Kalitta Air retired their last 747-classic (747-200 N793CK) in 2017; that particular aircraft arrived at AMS in the afternoon of April 13, 2017.
She departed to JFK on the morning of April 14 and this was the last ever visit of a 747-classic at Amsterdam Schiphol Airport.
See: viewtopic.php?t=1361117

That was exactly 46 years, 9 months and 13 days after the very first 747/747-classic arrived at AMS when Pan Am's N737PA "Clipper Red Jacket" came in from JFK and later went on to Brussels.

July 2, 1970:
Image
Image

Unfortunately I can't find a photo of Kalitta's N793CK on her last stop in Amsterdam; but this photo of her was taken at Toulouse; her prior stop to AMS that date:

Image
BOEING 747-222B KALITTA AIR N793CK MSN673 (MIAMI (MIA)-TOULOUSE(TLS)) A L'AEROPORT TOULOUSE-BLAGNAC LE 13 04 2017. by Jérémy Le roch, on Flickr

No 747-classic operates to Western Europe anymore. The only remaining 747-classics (about 2 dozen) are based in Eastern-Europa or the Middle-East and only fly in those regions.
But one of them (Georgia's The Cargo Airlines 4L-GEO) visited London Stansted in April this year.
And there are remaining 8 747SP's, mostly active in the US and also again the Middle-East.
Recently Royal Flight of Oman's A4O-SO sometimes visits London Stansted but that's about it.
(I have a Flightradar24 alert for any 747SP activity in the neighbourhood of the Netherlands and that's the only aircraft I get alerts from)

So there's pretty much NO 747-classic (-100, -200, -300 and -SP) activity on the continents of Europa, South-America, Africa, Asia and Australia.
Only very limited activity in the Middle-East and the US.
Last edited by Iemand91 on Thu Nov 01, 2018 1:59 pm, edited 2 times in total.
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leghorn
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 1:55 pm

maybe a 737Max200 when it appears will slip in to the cheapest band but a 737Max8 will not otherwise it is at a disadvantage to the 320neo. Same for a Dash8 86 seater; it could maybe justify a borderline decision for a cabin refit.
 
tvh
Topic Author
Posts: 145
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 3:16 pm

frigatebird wrote:
Interesting indeed. Above aircraft types are examples mentioned in the article, there are more on the list of course (like the AN-124 I suspect, although it's a rare visitor). The article mentions it's not just noise, pollution is a factor too (CO2 emissions for example). This could explain why an A321 has to pay more than an A320, and a 77W more than a 77E. Funnily enough, the 764 is cheaper than the 763!).


Well the article says that they want to encourage airlines to use cleaner and quieter aircraft.
However it does not mention taking cleaner into account with the categories.
From 2021 the first category get a penalty of 80 % on landing fee’s. The highest category get a discount of 55%. If you calculate the difference you end up with the first category being 4 times more expansive. But it is true that those aircraft already no longer visit schiphol. Most current aircraft are in the S3 category which is the base. Getting 55% discount is something to think about. I can see some airlines switch there new a320neo’s to schiphol as soon as these rule’s come active.
 
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Channex757
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 3:26 pm

FlyingHollander wrote:
I saw the article too and share your thoughts. Really interested in how these classes were determined.

Manufacturers supply extensive noise data with new aircraft sales proposals. SQ was instrumental (for instance) in getting the A380 engines reworked to ensure they were quiet enough for early arrivals into LHR.

It's especially important these days with noise curfews becoming more widespread.
 
phollingsworth
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 3:43 pm

leghorn wrote:
maybe a 737Max200 when it appears will slip in to the cheapest band but a 737Max8 will not otherwise it is at a disadvantage to the 320neo. Same for a Dash8 86 seater; it could maybe justify a borderline decision for a cabin refit.


I don't know how the Dutch are determining their categories, but it might be very similar to Quota Count. Using EASA's Noise Certification info, in this case the max MTOW A320NEO (79 tons) has a departure QC of either 0.125 (-251N) or 0.25 (-271N), while the 737-8 (82 tons) is QC 0.25. On arrival at MLW the A320NEO is QC 0.125 and the 737-8 is 0.25. The A321NEOs are all solidly in the QC 0.25 category for both departures and arrivals. I would not expect the 737Max200 to be quieter than the 737-8, unless the MTOWs come down a lot, so it will still be QC 0.25 for both, but it will carry more passengers.

On a side note the LEAP powered A320NEOs tend to be just a little bit quieter than their PW powered counterparts, at the same MTOWs.
 
VSMUT
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 3:47 pm

na wrote:
As for Russian planes, which ones are still operated into Western Europe? Havent seen any for years at least at FRA.


I've come across the An-12, Il-76, An-26, An-30, An-32, An-124 and An-225 in the last 6 months. Especially the An-12 I seem to come across everywhere in Western Europe: in Sweden, Norway, Switzerland, Germany, France, Spain and especially Italy.
 
n797mx
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 3:56 pm

Lufthansa wrote:
What is even more odd is they seperate the A321NEO and the A320NEO.


I can't say much about the NEO yet, but with the CEO there is a noticible difference. I'd go almost as far to say the A321 is right up there with the MD-80 on takeoff.
Clear skies and strong tail winds.
 
phollingsworth
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 3:56 pm

tvh wrote:
frigatebird wrote:
Interesting indeed. Above aircraft types are examples mentioned in the article, there are more on the list of course (like the AN-124 I suspect, although it's a rare visitor). The article mentions it's not just noise, pollution is a factor too (CO2 emissions for example). This could explain why an A321 has to pay more than an A320, and a 77W more than a 77E. Funnily enough, the 764 is cheaper than the 763!).


Well the article says that they want to encourage airlines to use cleaner and quieter aircraft.
However it does not mention taking cleaner into account with the categories.
From 2021 the first category get a penalty of 80 % on landing fee’s. The highest category get a discount of 55%. If you calculate the difference you end up with the first category being 4 times more expansive. But it is true that those aircraft already no longer visit schiphol. Most current aircraft are in the S3 category which is the base. Getting 55% discount is something to think about. I can see some airlines switch there new a320neo’s to schiphol as soon as these rule’s come active.


I didn't read the article, nor look at the new terms, so take my comments as an educated guess. However, my guess is solution has more to do with Take-off and Landing emissions, e.g. NOx, CO, etc and less to do with total CO2 as this would, potentially, fall afoul of the Chicago convention. Though they could include Terminal CO2 in their calculations, as these are certified and give a margin to the latest CAEP standard. While these would tend to push airlines, all else remaining equal to quieter, lower-emissions aircraft you won't see anyone currently operating a 737-800, A320CEO, but not NEO or MAX switching to a new aircraft, the landing fees are just too small of a portion of cost to justify the purchase. Depending on exposure and the delta in fees between the best and second best you could see it have an effect on future purchasing decisions or scheduling of a mixed fleet. However, there are so many other factors that come into play, to predict for sure who is going to do what.
 
phollingsworth
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 4:19 pm

phollingsworth wrote:
tvh wrote:
frigatebird wrote:
Interesting indeed. Above aircraft types are examples mentioned in the article, there are more on the list of course (like the AN-124 I suspect, although it's a rare visitor). The article mentions it's not just noise, pollution is a factor too (CO2 emissions for example). This could explain why an A321 has to pay more than an A320, and a 77W more than a 77E. Funnily enough, the 764 is cheaper than the 763!).


Well the article says that they want to encourage airlines to use cleaner and quieter aircraft.
However it does not mention taking cleaner into account with the categories.
From 2021 the first category get a penalty of 80 % on landing fee’s. The highest category get a discount of 55%. If you calculate the difference you end up with the first category being 4 times more expansive. But it is true that those aircraft already no longer visit schiphol. Most current aircraft are in the S3 category which is the base. Getting 55% discount is something to think about. I can see some airlines switch there new a320neo’s to schiphol as soon as these rule’s come active.


I didn't read the article, nor look at the new terms, so take my comments as an educated guess. However, my guess is solution has more to do with Take-off and Landing emissions, e.g. NOx, CO, etc and less to do with total CO2 as this would, potentially, fall afoul of the Chicago convention. Though they could include Terminal CO2 in their calculations, as these are certified and give a margin to the latest CAEP standard. While these would tend to push airlines, all else remaining equal to quieter, lower-emissions aircraft you won't see anyone currently operating a 737-800, A320CEO, but not NEO or MAX switching to a new aircraft, the landing fees are just too small of a portion of cost to justify the purchase. Depending on exposure and the delta in fees between the best and second best you could see it have an effect on future purchasing decisions or scheduling of a mixed fleet. However, there are so many other factors that come into play, to predict for sure who is going to do what.


Ok, I found the charges, https://www.schiphol.nl/en/download/b2b/1540986245/35tPo4cNPGmykW42SqCkO0.pdf,

From 1 April 2019 the different per ton for an S6 and S7 is: €0.46 for day take-off or landing and €0.70 for a night take-off and €0.58 for a night landing. This means for 100 ton aircraft the total difference in landing fees would be, at most €128 between S6 and S7. In 2021 the difference will only be €129. This is unlikely to greatly swing any decisions. Also, the classifications in the article are "Conservative". This means that if the airline cannot provide data specific to the airframe they are operating, e.g. the specific noise certification values, then Schiphol will default to these classifications, which are the most "unfavourable".

Also, the more comprehensive document https://www.schiphol.nl/en/download/b2b/1540980593/3mbUt8j092KqwYgqIGEg8G.pdf shows how the noise categories are determined, it is purely cumulative margin to ICAO Chapter 3, S6 is -23≥EPNdb>-26 while S7 is EPNdb ≤-26. Looks like there is no specific callout for other pollution. Looking at this some 767-300ERs at the two highest MTOWs fall in S3 and some in S4, so it pays to give Schiphol the specifics for your aircraft.
 
Bealine251
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 4:29 pm

I live in the South East of England and get a lot of aircraft over flying at 32,000ft plus from Europe to North America and I can always recognise an A330 flying over. Definitely more noisier than other airliners.
 
M564038
Posts: 186
Joined: Sun Jan 03, 2016 11:16 am

Re: Noise of new generation aircraft.

Thu Nov 01, 2018 4:56 pm

As I said. Noise measurement is insanely complicated. Tonal vs. Broadband noise, weighting, time, which thrust setting do you measure. Wind direction and strength, temperature, moisture, exact altitudes, courses(lateral angles), speeds, angles of attack, flap, slat and speed-brake settings, what happens at a different wind direction and 10 knots higher approach speed with a different flaps/trust solution?
Available data just isn’t very good, and getting good, valid data up to an agreeable scientific standard is nearly impossible. Just too many variables, and way to hard to control them.
 
smartplane
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 7:14 pm

Engine OEM's and many major airport ownership groups are participating in CORSIA discussions, either pre / post main sessions, while some have observers / participants in meetings and working groups.

There is a move by airports to bundle emissions, noise and rubbish, rewarding the quiet, clean and efficient, perhaps to lobby for fewer operating restrictions. Suggestions include engine OEM's to furnish engine landing, take off and taxi telemetry data to an IATA data warehouse.

These costs are currently a minute component of total operating costs. That will to change.
 
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PatrickZ80
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 8:51 pm

Rara wrote:
I would guess that seat numbers played a role. It does make sense from a resident's perspective - you would rather have the noise of one A380 than six A220s even if a single A220 is a little less loud.


Personally I'd prefer six A220s. Indeed they're less loud which means that at a certain distance you won't hear an A220 and thus neither will you hear six A220s but you will hear that one A380.
 
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seabosdca
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Re: Noise of new generation aircraft.

Thu Nov 01, 2018 8:58 pm

It's clear that some aircraft are "loud," "medium," and "quiet" -- but finer gradations get insanely difficult. The picture can be so different depending on where you are standing.

Any dB measurement also isn't enough to convey what people hear. I live a couple miles away from the departure path from SEA when there is north flow, and from my location there is no aircraft I notice more than a RR 757. It's not the volume of the noise but the distinctive timbre. The loudest I hear regularly is the 744, but the noise isn't distinctive except for being loud; it's just an undifferentiated rumble.
 
phollingsworth
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Re: Noise of new generation aircraft.

Fri Nov 02, 2018 7:48 am

seabosdca wrote:
It's clear that some aircraft are "loud," "medium," and "quiet" -- but finer gradations get insanely difficult. The picture can be so different depending on where you are standing.

Any dB measurement also isn't enough to convey what people hear. I live a couple miles away from the departure path from SEA when there is north flow, and from my location there is no aircraft I notice more than a RR 757. It's not the volume of the noise but the distinctive timbre. The loudest I hear regularly is the 744, but the noise isn't distinctive except for being loud; it's just an undifferentiated rumble.


Very true on the fact that dB measurements at any specific weighting are insufficient to fully describe what you here. Each of the common weightings, eg A, B, C, plus PNL and ePNL we’re creating as approximations of what people pick-up on in different situations. For instance outdoors vs indoors. They are most probably outdated now. We know more about human perception and building construction, especially windows have changed. The RR powered 757s are probably the most distinctive aircraft operating today. They have a tonal peak no other aircraft has. The 744s will seem quite loud as they have quite a bit of jet noise and tend to have fairly shallow departures.

Incidentally we’re tend to judge airports’ noise impacts using a A weighted cumulative measure like DNL or DENL. If you are using this you can get a quick and reasonably good estimate of a single aircraft’s impact on the size of any DNL, etc contour using the Quota Count.

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