Sound of silence

How quiet do you want it to be on the airplane next time you fly? Sounds like a rhetorical question, but it’s not as simple as it seems.

When we develop an airplane like the 787 – or any airplane – we ask questions such as how quiet do you want it to be in the cabin? Along these lines we’ve surveyed passengers to find out how quiet it is during flight – and a key question is how they “perceive” quietness in the cabin.

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How do you perceive “quiet” in flight?

For instance, even though the Airbus A340 has lower sound pressure levels, the Boeing 777 rates “quieter” in studies. So what’s going on?

You may recall media reports earlier this year making a lot of noise about how quiet it was aboard the A380.

In stories about the A380 passenger experience, we read that even seated by a window, you could hear conversations on the other side of the airplane, or even several rows away. In some reports, when passengers mentioned that this might be a bit disconcerting, they were told that one might have to “get used to” eavesdropping on an airplane.

So, I wonder if this also means that we’ll hear crying babies many rows further away than on today’s airplanes? Or sounds from the galleys?

I don’t know about you, but my personal experience is that if you can’t sleep because you can hear lots of conversations, or other sounds, you’re going to be more fatigued when you arrive.

You’d probably agree that the most disturbing background noises are the random ones - talking, coughing, lavatory doors closing. How disturbed you are during a flight is a function of the degree to which the random noises rise above the background noise.

We think the difference between “perceived” quiet on different jetliners is due to the balance of background - or white noise - and ambient noise.

Think of this as a trade-off between the level of background noise that might drown out desired noises (a flight attendant being able to hear the passenger’s drink order) versus undesired noises (one passenger being able to hear every other passenger’s drink order).

That’s why some “white noise” can be desirable on an airplane, and even soothing (the difference, say, between the sound of a power saw in the background, or of a babbling brook).

So, listen, maybe passengers could “get used to” to eavesdropping on an airplane. But my guess is you’ll find it annoying.

Babbling brook? Yes. Babbling passengers clear across the cabin? Maybe not.

Comments (38)

Chris C (South Africa):

Well-said Mr. Tinseth! I fully agree with your take on cabin quietness. Great to read all the positive news circulating in the media regarding the phenomenal 747-8 programmes as well…roll them’ 747 orders in!!

Gordon Werner (Seattle, WA):

I personally like to hear the roar of the engines ... it is a very soothing effect ... what I don't want to hear, is people talking on their cellphones for hours on end ... or other people's conversations ... I really don't want to know what other people are talking about ... and I do not necessarily want them to hear what I have to say ... if I am simply talking to my seatmate.

Lumberton (Lumberton, TX, USA):

Good points, Randy. Hadn't given any thoughts to the noise that may be coming from *inside* the aircraft! How does one mitigate internal noise?

Saj (London, UK):

I guess the one benefit of being on any new(er) airplane such as the 777NG or 787 is that you won't have to eavesdrop on a couple of hundred other conversations compared to being on the upper or lower deck of an A380!

Bryan (Boston, MA):

You actually never examined the positive aspects of cabin quietness, just the negative aspects, shows how objective you are. According to polls in an aviation community, no one really found the B777 quieter, they either thought the A340 was quieter or there was no difference at all. I love Boeing planes but i think this has to be the most cheap and uninspirational blog you've ever written (not that the rest were really any better). Just a cheap excuse in case the B787 isn't as quiet. If you find the talking bothering you, then use the earplugs like you'd do in a normal noisy aircraft, honestly i don't see this oversilence as being an issue deserving a whole blog. Nice to see the B787 coming along well though.

Nigel C (Northland, New Zealand):

I think it's a balance and as you reduce airplane noise, you in parallel have to reduce cabin noise by acoustic roof tiling, seat heights etc.
Personally I'd like to see long haul noise reduced to 1/4 of a 747/400. With cabin noise reducing proportionally ( ie. the balance was retained ) and preferably a bit less cabin noise in proportion.
There is a difference though between long haul & short haul as I see in terms of the impact background noise has on flight fatigue and I mainly fly long haul.

Chris Gibson (Australia):

Thank you for your regular updates on your blog. I am finding them very informative and a worthy replacement for Randy 1. The milestone of the 737 reaching 7000 orders is truly amazing. I find it hard to explain how Airbus keeps stating that its A 320 series is the largest selling aircraft in history. I am sure that all the Boeing fans World Wide are keenly awaiting their first flight in the world changing 787.

Randy Rohe (Anchorage, AK USA):

While I understand the point you are trying to make, I must respectfully disagree.
I am a die-hard Boeing fan, but will be the first to admit that one of the traditional advantages of flying on an Airbus has been a quieter ride.
I absolutely loved my recent Transatlantic ride on an Airbus widebody. It was very peaceful.

These particular statements you've made seem like a poor attempt to excuse a Boeing effort at weight loss by reducing sound-insulation.

In short, I find engine drone quite fatiguing. Further, crying babies are going to be an annoyance on any flight I might take.
To allow an increase ambient cabin noise in an effort to "drown out" crying babies and talking passengers seems like a very poor joke.

I look forward to my first ride on a 787, but after this particular blog, I will bring a pair of earplugs in my carry-on.

Everett (Beijing,China):

I don't hate the roar of the engines . But many people hate it very much. So I hope the Boeing Company can make airplanes with “quieter” cabin. Well-said Mr.NG. I fully agree with your take on cabin quietness.

James (Honolulu):

I have to inform you that you are being roasted on the Airliners.net forum regarding your comments on cabin noise. You might want to rephrase, though I think "they" are missing your overall point.

As someone who can't sleep on an airplane, mostly due to the coach class seating than overall noise, my suggestion is that you let the flight attendants worry about the babies and other noise sources and simply concentrate on making the quietest possible airplanes. (I know you can't tell the airlines to buy bigger seats and add legroom.)

By the way, we passengers can also take care of ourselves; all I need is my noise-isolating headphones and my MP3 player and I'm good to go.

Also, although it is out of production now, you might want to consult with someone on how to make the 717 a quieter plane. Those engines generate a high-frequency whistle that is all too obvious. They sound weird, as well.

G (France):

Have you been in a very quiet restaurant with your wife or your girl friend? You have to whisper instead of talking normally if you don't want to tell everything to the people next to you.

Ken (Auburn, Wa):

It's interesting that Randy leaves off the "other" noises that people will start hearing as cabin noise levels come down more and more. A pressurized airplane does interesting things to the body. Their are a lot of other bodily functions that will make passengers realize they are stuck in a tube with 200 other stinky and nasty humans all sharing the same air source.

: )

Andreu (Girona, Spain):

I cannot agree more with Mr. Randy Rohe from Anchorage, AK USA: I love Boeing but the noise contamination is worse on my ears than any ambiance of talking or "baby cryings". I am a person that loves to listen to music while flying. The engine's noise level on a jumbo or a triple 777 make it much harder to enjoy music or watching a movie than if I fly an Airbus. And that is truth in my many hours of flying experience.
Mind you, apart from that noise issue, flying Boeing aircraft, especially the Triple 7, is an awesome experience.

Francis (Amsterdam, The Netherlands):

As a pilot I have to suffer the incredible loudness of your B737 cockpits on a regular basis. Despite regular use of noise suppression earplugs my hearing capabilities still have deteriorated noticeably over the last couple of years. I used to fly the (then) still McDonnell-Douglas MD-11, which in comparison was quiet bliss...

So I can only hope that future airliners will be _much_ less noisy than the B737 and I think the A380 will be a remarkable improvement over the current noisy state of affairs in aviation. Reading this blog I almost start to worry that maybe your own Dreamliner will not live up to its name, as I'd expect it to be _at least_ as quiet as the A380!

Sanford Barton (Denver, CO):

Perhaps there are technologies that could be used to generate a custom level of white noise, on a per passenger basis. This would come in handy as I may indeed want to eavesdrop on the converstation across the aisle. What if it's something incredibly interesting? Failing that, there is this concept I've heard about from the 60's called "The cones of silence".

Great work btw!

Peter:

I found Boeing 747-400 awfully noisy comparing to Airbus airplanes like A330 or A340. When flying for only two hours I don’t see a problem, but when on board for 6 hours or 12 or more it’s completely disturbing. This is why I take care of what airliner to choose when planning a trip. It’s an airliner who has A330 for sure.

ian:

While you may have a point, your point was lost and the whole post seemed unnecessary.

When I first read it my first response was "I'll have what he's having."

G (France):

Snorring sound is very annoying.

Tom:

I have never heard such a poor excuse. I can't believe my ears (pardon the pun).

To be honest, if the cabin was quieter most people would be a little more considerate and should the flight be overnight anyway you will find most people also want to sleep then there would be minimal chattering anyway and just a nice peaceful cabin.

On the A380 too, the noisy folk can always take there conversations to the bar! Maybe the airline could also introduce a "quiet coach" maybe the upstairs of the A380 (amaller Economy section) for those who don't want to be bothered for chatting and babies and want to read and sleep.

Maybe Randy would prefer to ban noisy people altogether and enjoy his white noise in peace.

I flew to the US recently on a Virgin A340-600 and did the return leg on a 747-400 with the same cabin features and trust me the Airbus is by far the nicer flying experience.

I'm not anti Boeing.. I can't wait to fly on the 787, but let's not forget it has not yet had it's first flight.

sebastien (Miami, fl 33133):

I think engine noise is by far the most anoying thing in the cabin. Imagine a night flight when everyone is sleeping; now, the only noise left is the engine. or the rushed air outside. I ratter have human noise than engine. If I don't wear those earplugs or one of those Bose noise reduction, I'll have to crank the volume at the highest level just to barely hear music on regular headphones.

Paulo VF (Portugal) (Portugal):

Hey Randy...sometimes you just have to accept that Airbus has won over you in some point! Airbus tends to produce less noisier airplanes...A380 is a BENCHMARK in sound comfort and silence! Is today´s blog entry an excuse to a probably noisier 787? Hey believe me...all aviation entusiasths will love to fly in an 787 because of all the new tech in it but A380´s will always make people fall in love for them for the same reasons...Long live Boeing...Long live Airbus!

Christopher (Sweden):

As a frequent train traveller i must say i really enjoy a silent ride. It would be great with an airplane as quiet as a modern train. People tend to be more quiet when the background noise level is low.

I think the 777 is the most comfy plane to fly. The only bad thing about it is the noise level. With lower noise it would be the perfect airplane! Hopefully the 787 will be as a 777, but quiet!

Al (Kota Kinabalu, Malaysia):

As much as I like Boeing 777 so much, but one thing that irks me about the aircraft is that the cabin noise level is a little higher than that of airbus (talking about Airbus A330, because this is the only airbus plane I ever took.) But I figured out that it actually depends on where you sit. If you sit at the back of the aircraft than its noisier. But when towards the front or around the wing section its quieter. And I found out about this onboard both on airbus and Boeing 777. But, hey, this is based on my experience. I think others do have different opinions about this...

Mark (Atlanta GA USA):

Personally, I have not noticed the noise level difference between a 777 vs. an A340. The truth is, the only airplane I consider excessively noisy is the MD-80, in the back section right by the engines (it sounds like you are in a blender), and the only airplane I have noticed as super quiet is the MD-90 at the very front. I will add the 737 is fairly loud right by the engines. But the noise levels of the 747, 757, 767, and 777 all seem fine. In fact, the loudest thing on the 767 is that annoying flap motor.

I remember reading when jet airliners were first built, there was a big discussion about how much noise insulation to put in them. The decision then was to allow enough of a level of background noise (air flow and engine noise) to exist to dampen the chattering voices in the next row.

It is amazing people will buy white noise machines for their bedroom to help them sleep at night but will complain about the dull roar of jet engines at cruise. Let me guess, the people who buy the white noise machines for their bedroom are the same people wearing the Bose headsets on the airplane with no music player attached.

Now why don't those 747 engines have the same effect on babies as vacuum cleaners and hairdryers? Or better yet, why don't the beverage carts stock baby Benadryl?

Robert (Long Beach, CA USA):

Possible add-on options for the A380 accessories catalog:
1. Noise Reduction Headphones for all seats
2. White noise generators to counteract the quietness
3. Noise dampening material such as styrofoam or ambient media signs (Ryanair will love the latter)
4. Cones of silence (a la "Get Smart" TV series) for private conversations

Jonathan (Highbury, U.K):

I was reading a response to your blog Mr. Tisneth on a different website and I thought I'd come here to read it lest it was taken out of context. However I have to say yours is a thoroughly lousy attempt at an argument for your noisy airplanes.

Primarily, you make it sound as if everyone on the A380 will be eavesdropping on one conversation. Surely if the majority of the plane was quietly attentive to one conversation as you assume, wouldn't that be reason to lower the voice of your conversation? Or to move that baby to the back of the plane? Or keep it down in the galley? In reality, there would be a number of conversations within the cabin as with any other plane not one conversation that everyone eavesdrops on. And those many conversations will cancel themselves out to provid the general background noise. Or it will be even much quieter since reduced cabin noise will mean those who are sane will further lower their voices or move their children to the back/common area.

My experience on overnight Airbus flights has been very rewarding as I enjoy the much reduced amount of noise. And if you don't sleep easily then there's always ear plugs to drown out your pettily nitpicked 'lavatory-doors' closing sounds.

I'm an Airbus fan and I have to say I look forward to flying within the calm ambience of their cabins. I anticipate my first flight with the 787 but I do hope this blog is not a prelude to an experience ruined on a noisy 787 cabin.

Raymond (Madison, WI, USA):

I understand the point of the topic but perhaps it would/could have been worded differently. After-all many major corporations and even the US Government spend millions on determining words that reach their Audiences as intended...

I'm really not sure what Aircraft I last flew in but neither was very big, only single decks. One at least had a bit more engine Noise, that high pitched sound another Blogger had noted. A low steady drone can be easy enough to sleep with but when the cabin is Over Pressurized those High pitched sound come to life!

I also understand the Comment regarding a cabin so quiet that you might hear quite literaly everything around you including every ones bodily functions. But I doubt any airline makes a Cabin that quiet.

For the Pilots. I understand they arent considered pay passengers so their areas may not be as well protected. But its really quite absurd that a manufacturer would intentionally allow the Crew cabin to be exposed to More Noise than other inhabited ares of the ship. Perhaps the crews should all carry cans of Great stuff foam to seal up the holes! I think that they are entitled to quiet, after-all, they are responsible for the well being of the air craft.

White noise and other automated systems that Regulate the amount of noise that would cancel out nearby sounds is certainly something a Aircraft should have. A cabin is packed enough without passengers Needing to be able to hear the converse or even lack of from all other nearby. Thats the stuff of movies.

As for sounds from the Galley. I do want to know when lunch will be coming. Any sort of electronically regulated sound system, could also slightly echo sounds from some areas of the ship. Other areas like the rest-room should never be heard unless it the door being Unlocked! Its also possible with such a system installed on say a super Quiet air craft to introduce artificial noise which could be then Turned off during a Movie, or during an announcement, then Gradually returned to normal after a period of time, thus allowing passengers to be focused when needed.

Keith Sketchley (Victoria BC):

So your design goal should be to get the engines making only white noise? :-)

While I recognize that sales people need to be eternally optimistic, I think that you will have considerable difficulty getting anyone to start listening to claims that an airplane can be too quiet.

You will have more success by leading with privacy.

C Fong (Canton, MI):

I think you are full of nonsense. No aircraft cabin is anywhere near being "too quiet". Most of the times when I get off a trans-Pac flight on a 747, my ear hurts because I had to crank up the headphone so much in order to hear the movie sound track.

I work in automotive industry. I remember years ago when Honda came out with the fold away 3rd row seat on their minivan, Chrysler came out and said, "well, we did a market survey. We found that people prefer putting wheels under the 3rd row seat so the seat can be rowed away". There were even commercials of this woman wearing high heels pushing a row of seat on wheels. But Chrysler of course didn't show how a woman on high heels could manage to unload the 3rd row seat from the van down to the ground all by herself. Anyone with half a functioning brain found that commercial lame and a stupid excuse of not being able to make a better product.

Same goes with your blog. Tell you what, let us passengers worry about cabin being too quiet. You just make the plane as quiet as you possibly can.

By they way, who said that A340 is perceived noisier than 777? I feel just opposite.

Aaron Silverberg (Seattle, WA):

Thanks for your insights.
My personal preferences are for noise-cancelling headphones. I also would like to see future aircraft designed to allow people to change positions (lie prone, stand up with good handrails, seated meditation position). The key is to make air travel as "natural" as possible. Since traveling on an airplane is much like crossing a desert (airplane air is even drier!),
I'd like to see better hydration, misting for sinuses and face. And of course the most important item on an airplane is air filtering, so that people are not making each other sick.
If the atmosphere could be made more comforting even to small children (yes the pressure will still affect their sinuses).
One way to stimulate quiet, would be personal computer displays that showed detailed geographic information on what you were looking out at (you could plug your laptop into an on-board computer that ran GPS software, etc.), because the greatest thing about air travel is how much you get to see, so fast!!!
Would it be possible to run negative ionizers to create that fresh-air feel right after a thundershower?
I wish Boeing would hire me as a consultant to
help engineers improve air travel comfort.

Ash (London):

To Chris from Australia who asked about Airbus's claims of the A320 being the largest selling aircraft, I think you will find that they base it on comparative sales since the A320 came into being. ie, the A320 has outsold the 737. Subtle difference there. It is a bit hard to compare apples with apples when one, the 737 has been in the market for 20 years longer.

As for noise, yes some noise is needed, but as others have pointed out this blog seems like an excuse for Boeing to not do quite the same good job as Airbus has done. If you want noise then there are other ways of getting it.

Rohan Kapoor (Denver, Colorado):

It depends which engines your Boeing 777 has will determine how quiet or loud your aircraft is. For instance, the PW engines (United Airlines) and the RR Trents (some BA and all Singapore Airline's 777s) are very quiet and these two variants are WAY quieter than the old Airbus A340-300s. The GE90s on the other hand are kind of loud (some British Airways, Continental Airlines, Air Canada 777s), but these engines are still much quieter than the old Airbus A340-300 or the Boeing 747-400. However, in 2000 when Airbus release the next generation Airbus A340-500/600 series these planes are really quiet, definately quieter than the 777s with the GE90s, but are about the same as the Boeing 777 with the RR and PW engines.

Also, according to the FAA at lighter loads the Airbus A340-500/600 is quieter than the Boeing 777, but at heavier loads the Boeing 777 is quieter than the Airbus A340. Overall, both the Airbus A340 and Boeing 777 are quiet airplanes and are much quieter than the older Boeing 767 and the Boeing 747-400. Here's to the new "quiet" Airbus A380, the upcoming "super quiet" Boeing 787 and the Boeing 787/

Rohan (Denver, Colorado):

Personally I found Randy's comments to be quite valid, as a completely silent plane would be just as bad or even worse than a super loud plane. That being said I wish that planes could be a lot quieter as engine roar still is a big noise factor and I wish that planes could be at 35% quieter than the Boeing 747-400.

As for Airbus being the "quiet" manufacturer I highly disagree. The Airbus A320 is way louder than the Boeing 737 and the Boeing 777 is way quieter than the old Airbus A340-300. However, the Airbus A340-500/600 series or the "next-generation Airbus A340" is very quiet, but its only few decibels quieter than the Boeing 777. Personally, I find the 777s with the GE90 engines have the loudest cabins, while the 777s with the Rolls-Royce or the Pratt and Whitney tend to be quieter. Overall, I prefer the Boeing 777 because it climbs faster, is smoother, and has a better cabin design than the A340.

Also, please stop blasting Randy, as his ideas actually make a lot of sense, I would never want to be on a plane where the engines made no noise, but I wish that today's aircraft could be a little quieter.

Richard Mahoney (Everett):

The A340 is a very quiet airplane - which apparently is due to their foam core insulation blankets - similar in design to that which was on the initial 777s. However, the A340 has cabin conditioning issues which is apparent to cattle class passengers. Many A340s I have been on had heated floors around the galley and main entry doors because of their poor temperature control. There temperature control challenges is no secret to passengers because I also have seen strip chart recorders in pursur stations on A340 revenue flights collecting cabin data. The A320 is very noisey - has alot of hydraulic actuation noise particularly in the tail where the yaw damper frequency is apparent by the constant swish-swish .. I think the 747 nose gear snubber is "alarming" to those in first class that have never flown on a 747 before. But I agree with one comment - I love the roar of four 747 engines on takeoff - but only on takeoff !

Ron (Germany):

I´m ok with the airbus planes but in my sailplane I´d love to have some Boeing sound files in my iPod - it reminds me of the old days of thunderstorm ;-)

Capt Leon Pesche, ret. >22 000 Flying hours in 33 years (Moultonborough, NH USA):

As a pilot, I measured aircraft cabin noise with a noise meter, expressed in DBA ( decibel A)

On the ground, B734 engines stopped, APU running and Air-conditioning ON: 74 DBA. Engines running at idle, doors closed 74DBA. During T/O 84DBA. During climb, cruise and descend: the noise is directly proportional to the indicated airspeed! Engine full throttle or idle makes only a difference of 2 DBA.

250Kts IAS > 74 DBA, 340 Kts IAS 84 DBA.

As a PAP, I measured in a SAAB 2000 102DBA in the front cabin during T/O. In row 55 in the 747-300
112 DBA during T/O, 102 during climb and 94DBA during cruise. Due to the fact that the B 747 is still the fastest commercial airplane, this explains the highest noise level! Also in the cockpit one of the best noise levels have been in the old CARAVELLE, due to the aerodynamic form of the windows with the fuselage.

I tried with visitors at home to put the sound level on my TV showing video filming I took during flying only to 84 DBA,(IDEM to the noise in the cockpit 737 during descend at 300knots Indicated Air Speed(IAS) and all of them were shouting to reduce the volume, and asked me if I would be nuts? Funny they don't find it that loud when they are getting way higher noise up to 10 hours on a long-range flight?

If I measure the noise next to the "AUTOBAHN", the noise level of the rolling traffic, is higher at the same distance from the runway where a B737-400 is taking off!

Samuel:

What's up with the "I told you so?" The A380 is still much better and modern (smoother outline) than the 747. HA!

Tomas (Japan):

I agree with the blog, but also I think it`s a kind of excuse. I will still prefer quieter airplane, because even A330 seems to me noisy (especially when I want to listen to music).

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