aguilo
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Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 6:41 pm

Anyone ever notice on how Airbuses there is always this very "rough sounding" roar on takeoff as if the engines are going to self destruct any second? What is the reason for this?

Only occasionally hear it on a B737 (probably when they are using full power for takeoff) but never hear this sound (kind of like the sound a 4 cylinder car would make if you were steadily redlining the engine) on another Boeing, ERJ or CRJ aircraft.

Any explanation?
 
aircadet
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:01 pm

Most of my travels are on Airbuses 319-320-321 and occasionally on 737's but don't recall ever hearing such noises, The airbus if anything whines a lot and the 737 seems to have more of a grawl.
Which airbuses were they.?
tlaqna hi
 
Q330
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:03 pm

Which airbuses do you hear this on?

-Q
Long live the A330!
 
Andreas
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:18 pm

It's always a pleasure to see new and exciting forms of Airbus-bashing, innovative...and ultimately as nonsensical and useless as all forms of A (or B) bashing.

Well I never ever noticed such a noise, neither on B nor on A, but then I rarely fly Airbus...only about 150 times per year, throw in another 100 Boeing flights, so I don't really qualify to judge such "whiny, redlining, itsy-bitsy plastic" noises, which are produced, btw, by the engines, and afaik, Airbus does not manufacture any engines, neither does Boeing!


Mods...can we stop this please?  Angry
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BestWestern
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:50 pm

Wondering if that roaring noise on Airbus frightened US UA and AC customers away and caused their CH-11?  Smile  Smile Maybe we have found the source of their problems.

Sometimes I really dispair at this site... I think Civil Aviation needs to be split in two...

1. aircraft related questions (what airline flew you first on a 777, etc...)
2. airline related questions (why is Ryanair so cheap?)
You are 100 times more likely to catch a cold on a flight than an average person!
 
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Starlionblue
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:53 pm

The roar is the result of thrust, which in turn creates lift. I'll take the roar over standing still at the gate Big grin

I think that Aguilo is referring to the "buzz-saw" sound. Many modern engines sound like that.

"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
Udo
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:54 pm

Oh, now I see who suggested my posting for deletion...heroic action, but why not use some glasses which might help to see smileys?  Wink/being sarcastic

Btw, I know what sound is meant by Aquilo. My impression is that CFM-equipped A320s produce that sound more intensively than IAE-ones.


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Udo
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pelican
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:56 pm

Just in case this isn't a new try to bash Airbus I want to add that I have also heard something...
I wouldn't describe it as a rough roar but there is definitely in front of the engines of an A 32x a specific noise which I haven't heard in a 737NG.
The first time I heard it was when I sat in front of the engines in (~7th row) an Aer Lingus A321.
But on the other hand I have noticed that 737NGs are much louder behind the engines.


 
aircadet
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 7:57 pm

People please, chill out, have a coke and a smile  Smile
It's a forum if you don't like whats being discussed don't reply or comment.

If i see something which sounds the same(ryan air / B or A/ WHIC 777/330 etc I just switch topic).

Come on guys  Smokin cool
tlaqna hi
 
Andreas
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 8:01 pm

Just to avoid misunderstandings: I did suggest deletion of THE WHOLE THREAD, not a single post, and I said it openly in my first post here. Other than that, I really do not care about who posts what, but in this case, I had the pre-easterly egg-finding urge to point out the rather A-bashing nature of the thread per se  Big grin.

btw: as can be seen, I do know how to use smilies, so don't jump to conclusions, angry young man  Smile


Ignore threads? I do that most of the time, but not if it's against a clear regulation of the Forum, and A vs. B is such a regulation!

And btw: I didn't say it was a seen-it-all, on the contrary, it's rather innovative Big grin

Happy holidays!

[Edited 2004-04-07 13:05:42]
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solnabo
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 8:03 pm

Maybe Airbuses roar due to RR/GE´s/ CFM, but have you heard a 737-200 taking off? Puuhleeeze.......
A smaller earthquake IMO!
Sorry, dont drink Coke/Pepsicrap, only Ramlösa or Avignon for me  Smokin cool

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Udo
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 8:10 pm

Did I address anyone specific? Sorry, cannot remember...that's probably caused by reduced pre-easterly food consume...  Wink/being sarcastic


Regards
Udo
Me & You & a Plane Named Blue...
 
pelican
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 8:11 pm

I think Udo is right about the CFMs - I never heard the "buzz-saw" sound in a BA A 319-131...

 
JGPH1A
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 8:16 pm

This thread is not Airbus bashing - for some reason, I have noticed that there is a very distinctive low pitched noise when many Airbus aircraft take off - it is most peculiar. I noticed it on Sunday, watching an AF A321 take off at NCE. It sounded very different to the Easyjet 73G that had taken off before. It is not just Airbus narrowbodies either, AB3's have it too. It must obviously be some feature of the engines these aircraft carry, but it is definitely there.

P.S. I am most definitely pro-Airbus, this is not a criticism, just an observation.
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VSGirl
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 8:17 pm

On the baby buses I always find there is more of a wine at take off... I am normally in Business which is just in front of the engines, sometimes just in front of the wing or on top of the wing the noise can sound more aggressive.

I remember being on a Boeing 777 back in November and thinking the engines sounded like a grass cutter. It was on a British Airways B777, GE fitted. It was a very intriguing sound.

Kimberly.
 
isitsafenow
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:10 pm

Im kinda glad they do make noise. I miss the old 707 and DC8 waterburners when noise was king. When they develop a total quiet jet engine, I'll go back to watching trains. The noise and smell is half the fun at the airport.
safe
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JBirdAV8r
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:19 pm

This has been discussed many times, I believe.

From what I gather, it's a noise specific to the CFM engine on the Airbus A320 series, of the tips of the (N1?) fan going supersonic. An exciting sound, eh?

(and yes, this happens in other aircraft too. If you've ever heard an IO-550 Bonanza at full tilt and close range...you'll see what I mean.)

It's always a pleasure to see new and exciting forms of Airbus-bashing, innovative...and ultimately as nonsensical and useless as all forms of A (or B) bashing.

Oh Andreas, come off of your high horse. No one mentioned a negative thing about Airbii. It's a legitimate question. Comments like YOURS detract from the forum.

[Edited 2004-04-07 15:20:40]
I got my head checked--by a jumbo jet
 
a3xx900
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:28 pm

I think I know the sound we're talking about here... but I remember this sound only from older 737s, like -300s and -400s. I dunno what engines they use. IMO Airbuses sound rather like a vacuum cleaner from the inside.
But generally, this is not a question of A or B or C or whatever, it's a question of the engine.... Both Boeing NGs and Airbus use CFM56 engines and IAE engines. So it would be interesting to know on which engines you heard these sounds?
Isn't the sound the engines make on T/O the best thing in flying anyway? No matter if it's a huge PW4600 or a small CFM56? A or B?  Smile

And for Andreas... calm down. Mind your blood pressure.  Smile
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aircadet
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:32 pm

Solnabo: Not the drinking kind  Nuts
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Horus
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:38 pm

Why is it that when an aircraft begins its take-off role, for the first few seconds the engine sound is 'low' then all of a sudden the power goes up so much? It is most noticeable on a 744. What is the reason?
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a3xx900
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:43 pm

Horus: I'm not a pilot, but I think the thrust levers are pushed forward to only 60% N1 thrust to see if the engines are ok and the readouts are the same for both (or all) engines. Then, if everything is Ok, they push the thrust levers to max or FLEX or whatever the pilots desire.
It also takes some seconds for the engines to reach their max thrust.

Again: I'm not a pilot and my apologies if I said something wrong  Innocent

[Edited 2004-04-07 15:48:10]
Why is 10 afraid of 7? Because 7 8 9.
 
SW733US
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:43 pm

Horus:
The sound you are trying to identify belongs to the engine turbine going to "take off" power. Otherwise, the jet engines are left in a "ground" power which provides enough thrust to get around on the deck.


 
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Starlionblue
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 10:54 pm

The Avro100 makes a similar sound actually. Deep and growly. It's especially audible when going to a higher FL.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
cadet93
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:10 pm

OK I am not an engine expert...And I do fly a lot each year. I only fly for pleasure and still manage to fly about 50,000 miles a year. When CO had A300s in their fleet, I noticed that the noise inside the plane was definitely louder than any other plane I had flown. Even more so at take off. This is the major reason I like the less obtrusive sound level in the Boeing. Maybe because its cabin noise levels are at a lower decibel than in the Airbus.
Since I only fly on Boeing now because of CO, I can not say what the new Airbus sounds like. When I get the chance to fly one, I will most definitely be checking this out.
 
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Starlionblue
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:12 pm

A340 is quieter than B777, both from anectodal reports and actual measurements.

A319-A321 is in my experience quieter than 737NG.

But for silence, nothing beats the front of an MD-90!
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
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longhauler
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:12 pm

I agree.

I fly the A319/A320/A321 for AC, and the CFM engines make a very unmistakable sound on takeoff, moreso on the A319 than the rest. In fact the A321 is disturbingly quiet on takeoff.

One passenger once commented to me that it sounded like a bicycle wheel when we were kids and you used to put a hockey card in the spokes attached with a clothes pin.

I think someone above has it right when he suggested that the blade tips of the N1 section are going supersonic during high power settings at slower speeds. It continues during early climb, but in the acceleration to 250K it disappears. And during cruise, or later climb with the same power settings but higher speeds, it is non existent.
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a3xx900
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:13 pm

Cadet93:
The new Airbuses are much quieter inside. For example I think the 777 is much louder than any modern Airbus.
But yeah, try to avoid the old busses... You can barely talk to your neighbor in them  Smile
Why is 10 afraid of 7? Because 7 8 9.
 
JBirdAV8r
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:16 pm

Horus:
The sound you are trying to identify belongs to the engine turbine going to "take off" power. Otherwise, the jet engines are left in a "ground" power which provides enough thrust to get around on the deck.


Sort of, but not really. With most airlines, the flight crew will "stand the throttles up and down" when applying takeoff power to assure both engines "spool" and are brought up to the same speed....all engine indications are normal...etc...then either set max power, pre-determined power, TO/GA, or move the levers into the FLEX detent or however the Airbus works (not really familiar with the system).
I got my head checked--by a jumbo jet
 
aguilo
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:28 pm

Just to clarify (since I started the thread):

1. This was not to be a bus basher of a thread, I really don't have any preferences betwen Airbus and Boeing and fly both regularly (I actually miss the oversized oval shaped windows of my USAir F-100s)

2. Those of you who referred to the sound as the "buzz-saw" sound are right on the money - that's the one I mean (couldn't find away to descibe it).

You only hear the sound if you are seated in front of the engines, but it is present on virtually ALL airbus aircraft. Most particularly present on the A300 and the A319s though from my own experience. But not limited to those.

On a recent flight aboard a VS A343 the person sitting next to me even asked "what is that strange sound" (the buzz-saw sound) that was heard when the pilot applied full power for takeoff. On another trip aboard a USAir A330-300 I was upfront in Envoy Class sitting next to a woman who was sleeping through taxi and takeoff and when the "buzz-saw" sound began on takeoff she woke up immediately in a panic - thinking there was something wrong with the plane. It's QUITE loud.

Seems you only hear the "buzz-saw" sound on the Airbuses but not the Boeings. When I have heard it on the Boeings, it is usually not very loud and only heard on the few occasions that they are using max power for takeoff.

Could it be the design of the cabins on the Airbuses that lets more noise from the engines in or something?
 
pelican
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:51 pm

Yeah that's it - a buzz saw on all A32x with CFM. I never heard it in another plane than in an A320/21. An I have never heard it on a BA 319 (they are equipped with IAEs).

 
erikr
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RE: Airbus Takeoff Engine "Roar": Why?

Wed Apr 07, 2004 11:57 pm

Below is from Frontier Airline's web site's FAQ about "grinding" noises on the A319:


Q: While we were still parked at the gate, when we were taxiing and while the landing gear was retracting and extending, I heard a grinding or whirring noise coming from the Airbus A319. What was that noise?

A: The noise you are referring to, which is heard coming from the rear of the aircraft, is the result of the pressurization of the hydraulic system and the eventual equalization of the system on the aircraft. You'll hear this sound on most commercial aircraft, including the Airbus A319. The sound will be heard during the approach until all landing gear has been retracted and also upon landing gear extension. This is usually during taxi right before take off and again during taxi right after landing. This sound is very normal and you can be assured that when you hear it, the plane is functioning properly.
 
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Starlionblue
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 12:39 am

The DC-10 is well known for the buzz-saw.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
egnr
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 1:16 am

From what I've observed (externally), the "buzz-saw" sound is a characteristic of the CFM powered Airbus single aisle family, the IAE powered ones do not seem to make the same noise. I haven't flown on an Airbus, so can't commetn on cabin noise.

However, a few years back I travelled to Las Palmas with Air 2000, and the 757 that brought us back made a similar noise in the cabin. The 757 that took us out to Las Palmas didn't do it, and I've not heard it on other 757 flights with Flying Colours.

A few times at Manchester Airportm I've heard other Air 2000 757s making the same noise on take off, almost always the older examples in the fleet.
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JBirdAV8r
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 1:32 am

ErikR,

Below is from Frontier Airline's web site's FAQ about "grinding" noises on the A319:

That sound is another thing entirely.
I got my head checked--by a jumbo jet
 
captaink
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 4:44 am

This is the airbus take off sound.

Vacum - growl - whine -louder whine - Louder growl + buzz

The B737 doesnt really sound much different in my opinion.

I have been on the A319/320/321, B733, B734, B738.

The quietest and sweetest of them all is the A319..
There is something special about planes....
 
Continental
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 5:40 am

Andreas: I found no form of Airbus-bashing here. Person asked a valid question, let it be.

Anyway, I've heard the 'whine' before, but never the roar. Last time I took an Airbus (NWA MCO-MSP Aug 26th, 2003) I didn't notice it! I'm taking an Airbus (UA MSP-DEN Apr 30, 2004) so I'll listen then!
 
Westjet!Eh!
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 10:58 am

I agree with you that I have also heard that the airbus engines were roaring when take off and landing but in cruising, it is quiet and normal. I have never heard that Boeing's engines making noise like this. I have flown all the boeing aircraft and some airbus aircraft (A300B4, A321 and A330). I found that the sound of the airbus engines are different to the boeing's engines.
 
ANA777Master
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 12:13 pm

Its quite ironic that the engines roar like they do, yet have unimpressive linear acceleration. I also think that the engine cowlings/nacelles are not as thick/sturdy, and hence create strong, low-pitched reverberations.
 
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EK413
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 12:17 pm

Aguilo

Anyone ever notice on how Airbuses there is always this very "rough sounding" roar on takeoff as if the engines are going to self destruct any second? What is the reason for this?


I recently flew on a QF A333 'Broken Hill' and I found the take off & landing very quiet & smooth!
I wouldn't have a clue which aircraft you have heard these "Rough Sounding" from?  Confused


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USAIRWAYS321
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 12:31 pm

See, different from many of you above, I've flown the 319, 320 and 321, but I've heard the buzz-saw sound most often and loudest on the A321. Oh well, it's a great sound IMHO.
 
XFSUgimpLB41X
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 12:37 pm

The buzz saw sound is characteristic of any high-bypass turbofan plane. You can hear it on the CRJ, though it is more of a "eeeeeeeeeeeee" than a "grrrrrrrrrr", ... The 757 and larger birds have the same noise, just deeper. Bigger engines, deeper noises.

The buzz saw is very apparent in first class on the A320.


I jumpseated on one today.... what an amazing cockpit! Those sidesticks make it so nice... FMS is very similar to whats on the CRJ... FMA has a slightly different logic than the boeings, but is easy to understand nonetheless.
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cvervais
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 12:41 pm

Ok I"m no expert but I'm not buying the blades going supersonic theory.

The reason why is I'm assuming (maybe incorrectly so please kindly correct me if I'm wrong) that we'd hear a similar noise on engines with a greater fan diameter.

Assuming the shaft of the differing engines is spinning at the same RPM, the tips of the fan blades on the larger diameter engines will be going faster than those on a smaller diameter engine.

But perhaps it's a reverb thins and the length of the blades adds a harmonic resinance thus the unique noise.

Or it could be that darn theta band emissions again, they'll get you every time.  Wink/being sarcastic
 
NWFltAttendant
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 12:53 pm

I can personally attest to these noises. The loud roar on takeoff is very noticable on the A319/A320 when sitting in the forward jumpseats. The 319 does it the worst. If you listen to ATC ever, you can usually tell which pilots are calling from Airbus aircraft, you can hear it in the background.

SPEAKING OF OTHER AIRBUS NOISES

Quite frequently, as in every single flight, you hear a sound similar to somebody throwing rocks at the side of the plane. It is always occuring in the aft galley on the A320 family 'busses. Its most commonly hear in the final third of the flight. Once again, another noise on the airbus that you never hear on any other aircraft, be it Boeing, Fokker, MD, Canadair, Embraer, or any other manufacturer.
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XFSUgimpLB41X
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RE: Airbus Takeoff Engine "Roar": Why?

Thu Apr 08, 2004 1:14 pm

Cvervais... your quote "The reason why is I'm assuming (maybe incorrectly so please kindly correct me if I'm wrong) that we'd hear a similar noise on engines with a greater fan diameter."


Read my post.. you hear this same noise on all high bypass engines at t/o power, typically to a slightly lesser degree when using flex thrust. You wont hear it when you are sitting behind the engine, only in front. The bigger the engine, the deeper sounding the buzz saw noise.

That grinding roar when sitting on the pointy end of the 747-400 after the gear comes up..... one of the most amazing sounds ever.
Chicks dig winglets.
 
aguilo
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RE: Airbus Takeoff Engine "Roar": Why?

Fri Apr 09, 2004 8:28 am

Actually the bigger the turbofan diameter the SLOWER the blades are spinning as compared to a smaller fan. Just like a small wheel makes more rotations to cover the same distance as compared to a big wheel.

The buzz-saw sound is in fact most prevalent on the A319, I just wonder why is it that if it has something to do with the fans going supersonic, that you only hear it on the Airbus a/c and not the Boeings, or if anything not nearly as loud (you certainly don't hear it over ATC radio in the background on Boeings)

Also, the sound is definitely present on larger Airbuses as well. As I mentioned before I've been on flights where people were absolutelty terrified by the infamous buzz saw sound on A333s and A343s.

Rarely if ever here it on Boeings. Could it be that Airbus's use an engine type not offered on any Boeings and that the buzz saw sound is just part of the engine design?
 
asuflyer05
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RE: Airbus Takeoff Engine "Roar": Why?

Fri Apr 09, 2004 8:39 am

Also, the sound is definitely present on larger Airbuses as well. As I mentioned before I've been on flights where people were absolutelty terrified by the infamous buzz saw sound on A333s and A343s.

Rarely if ever here it on Boeings. Could it be that Airbus's use an engine type not offered on any Boeings and that the buzz saw sound is just part of the engine design?


Different planes make different noises. Just like a Ford Mustang sounds a little different than a Honda Civic. I'm flying an A320 and a 757 tomorrow. I'll see if I can ask the pilot what the cause is from some of the specific noises.

Matt

 
N243NW
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RE: Airbus Takeoff Engine "Roar": Why?

Fri Apr 09, 2004 8:55 am

The DC-10 is well known for the buzz-saw.

Indeed, I'm surprised it took so long for someone to finally mention this. When I think of the buzz-saw noise, the DC-10 immediately comes to mind. Yes, the noise is produced as a result of the N1 fan blade tips exceeding the speed of sound. It is only heard clearly in front of the engine's intake. However, the DC-10's buzz-saw noise can be heard well from the rear of the aircraft, due to the #2 engine. I usually hear the noise go away after 10 or 15 minutes of climbing as the pilots pull the thrust back from takeoff/initial climb power. The worst moment of any DC-10 flight! Sad
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JBirdAV8r
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RE: Airbus Takeoff Engine "Roar": Why?

Fri Apr 09, 2004 9:11 am

As a side note re: the DC-10...

I notice the sound very well in the forward sections of the CF6-powered Boeing 767's as well. After all, it's basically the same engine...or a very close variant. Wish I could find the video with the sounds on there.

Didn't notice it as much in the PW-powered 76 but maybe that had more to do with my seating position.
I got my head checked--by a jumbo jet
 
MD11LuxuryLinr
Posts: 1311
Joined: Tue Jul 22, 2003 8:34 am

RE: Airbus Takeoff Engine "Roar": Why?

Fri Apr 09, 2004 9:14 am

..."The DC-10 is well known for the buzz-saw. "...

Of course, I love the DC10 and the noises it makes on takeoff. BUT, there is one aircraft that sounds even better.. the L1011. Nothing beats the sound of those RB211s when they're wound up.  Big thumbs up
Caution wake turbulence, you are following a heavy jet.
 
tristar2000
Posts: 259
Joined: Mon Dec 11, 2000 8:18 am

RE: Airbus Takeoff Engine "Roar": Why?

Fri Apr 09, 2004 11:43 am

MD11LuxuryLinr,

I was waiting for someone to mention this... I also believe nothing beats the sound of those RB211s at full power on L-1011 takeoffs.

As for the thread itself, you don't have to be in the cabin to notice the sound we're talking about here. I work on the flightline and in the hangar, which are both alongside runway 06R/24L in YUL. When A/C line up on 24L and wind up for takeoff, even if you don't see the plane, you can take a guess just because of that sound.... the 319/320/321 really make that particular noise... and since AC represents maybe 95% of the A320 series in Montreal, you have a pretty good idea it's them. As for Jetsgo and Westjet and other A/C, they truly have a different sound to the ear. I'm sure anybody hearing planes takeoff day after day can easily distinguish the 2.

AC 767s also make the buzz-saw, but it's maybe a little deeper than the busses.

It hasn't been mentioned, but when it's humid (fog or mist around the airport), the buzz-saw sound seems to be even more perceptible, can someone comment??

Best regards,
Steven  Smile

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