FlyASAGuy2005 From United States of America, joined Sep 2007, 6520 posts, RR: 11 Posted (4 years 8 months 1 week 3 days 21 hours ago) and read 7357 times:
To hear what I am talking about, you must be sitting either right next to the engine opening or forward of it all together (low wing engines).
I've always noticed on take-off as the throttles are advanced, you hear the scream of the engine but then it is overtaken by a low pitched "wang" noise. A good example is in the bellow video, or any video shot in the front of coach or first class. The engine "scream" as I call it starts at about 00:32 and the "wang" noise takes over pretty quickly at around 00:34 - 00:35.
I've been told by enthusiasts that the sound i'm hearing is the blades moving faster than the speed of sound. Sounded pretty crazy to me but more than one person has given me this explanation.
CAM2:"Lightning coming out of that one." CAM1: "What?"
Tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80 Reply 1, posted (4 years 8 months 1 week 3 days 20 hours ago) and read 7340 times:
Quoting FlyASAGuy2005 (Thread starter): The engine "scream" as I call it starts at about 00:32 and the "wang" noise takes over pretty quickly at around 00:34 - 00:35.
Quoting FlyASAGuy2005 (Thread starter): I've been told by enthusiasts that the sound i'm hearing is the blades moving faster than the speed of sound. Sounded pretty crazy to me but more than one person has given me this explanation.
Correct. The fan blade tips are going locally supersonic.
Skoker From United States of America, joined Apr 2006, 439 posts, RR: 1 Reply 2, posted (4 years 8 months 1 week 3 days 20 hours ago) and read 7338 times:
Wow, 1 hour and change and nobody's ripped on your use of "wang" in the thread topic yet. A gleam of hope from the A.net population?
Lowrider From United States of America, joined Jun 2004, 3220 posts, RR: 11 Reply 3, posted (4 years 8 months 1 week 3 days 19 hours ago) and read 7305 times:
Quoting Skoker (Reply 2): A gleam of hope from the A.net population?
Hey, this is Tech/Ops, not to be confused with some of the Cretins in (Un)Civil Av.
FlyASAGuy2005 From United States of America, joined Sep 2007, 6520 posts, RR: 11 Reply 4, posted (4 years 8 months 1 week 3 days 5 hours ago) and read 7138 times:
Speedracer1407 From United States of America, joined Dec 2004, 333 posts, RR: 0 Reply 5, posted (4 years 8 months 1 week 3 days 2 hours ago) and read 7070 times:
Quoting Skoker (Reply 2): Wow, 1 hour and change and nobody's ripped on your use of "wang" in the thread topic yet. A gleam of hope from the A.net population?
I was gonna comment on that, but not for the obvious reasons. I'm not sure why anyone would describe a deep buzz-saw sound as "wang." Does wang sound like brap? Or quack? Or kapow?
Dassault Mercure: the plane that has Boeing and Airbus shaking in their boots.
Tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80 Reply 6, posted (4 years 8 months 1 week 2 days 21 hours ago) and read 7016 times:
Quoting Speedracer1407 (Reply 5): I'm not sure why anyone would describe a deep buzz-saw sound as "wang."
Among other things, I think of "wang" as the sound you get when one piece of metal bounces off another and vibrates. On some aircraft/engine combinations, if you fudge it a little bit, the "buzz saw" effect does sound kind of metallic.
Speedracer1407 From United States of America, joined Dec 2004, 333 posts, RR: 0 Reply 7, posted (4 years 8 months 1 week 2 days 20 hours ago) and read 6995 times:
Quoting Tdscanuck (Reply 6): Among other things, I think of "wang" as the sound you get when one piece of metal bounces off another and vibrates. On some aircraft/engine combinations, if you fudge it a little bit, the "buzz saw" effect does sound kind of metallic
Quite. I thought of the sound a saw makes when you bend it and let it flick back into shape. Thus, I was hoping for a long thread trying to diagnose such an unusual sound coming from a plane on takeoff.
As long as we're talking about the "buzz saw" effect, it seems that most enthusiasts assume that the world was introduced to that unique sound with the first big fan engines, like the JT9D. But I swear I hear it quite clearly on small-fan JT8Ds in any seat forward of the intakes on an MD-80 at takeoff. And in a recent cockpit video of a KC-135 with JT3Ds, the buzz saw sound could be heard loud and clear.
Dassault Mercure: the plane that has Boeing and Airbus shaking in their boots.
Mir From United States of America, joined Jan 2004, 19716 posts, RR: 56 Reply 8, posted (4 years 8 months 1 week 2 days 19 hours ago) and read 6972 times:
Quoting Speedracer1407 (Reply 7): As long as we're talking about the "buzz saw" effect, it seems that most enthusiasts assume that the world was introduced to that unique sound with the first big fan engines, like the JT9D.
I first heard it on a 767 with GE engines.
-Mir
7 billion, one nation, imagination...it's a beautiful day
HangarRat From United States of America, joined Jul 2005, 627 posts, RR: 0 Reply 9, posted (4 years 8 months 1 week 2 days 9 hours ago) and read 6867 times:
Quoting Speedracer1407 (Reply 7): It seems that most enthusiasts assume that the world was introduced to that unique sound with the first big fan engines, like the JT9D.
I think they were the first engines from which you could hear the fan sound on the ground. I remember summers as a kid playing in my grandmother's garden off the departure end of one of the runways at LHR wondering what made the big jets sound different.
Quoting Speedracer1407 (Reply 7): But I swear I hear it quite clearly on small-fan JT8Ds in any seat forward of the intakes on an MD-80 at takeoff.
I remember being surprised to hear it the first time I flew on a DC-9. Most of the flying I did until I was 20 or so was on 747s across the pond. Can't say I ever noticed the sound on 727s.
SPREE34 From United States of America, joined Jun 2004, 2097 posts, RR: 10 Reply 10, posted (4 years 8 months 1 week 2 days 8 hours ago) and read 6846 times:
Quoting Skoker (Reply 2): Wow, 1 hour and change and nobody's ripped on your use of "wang" in the thread topic yet. A gleam of hope from the A.net population?
The song is Wang Chung. Done by the Rolls Royces some time back. I think the had a few other hits in the 80s.
Quoting Speedracer1407 (Reply 5): I was gonna comment on that, but not for the obvious reasons. I'm not sure why anyone would describe a deep buzz-saw sound as "wang." Does wang sound like brap? Or quack? Or kapow?
Depends on accent.
It's a beautiful noise!
I don't understand everything I don't know about this.
USAIRWAYS321 From United States of America, joined Jul 2001, 1806 posts, RR: 10 Reply 11, posted (4 years 8 months 1 week 2 days 7 hours ago) and read 6805 times:
The buzzsaw is one of my favorite sounds. I first noticed it on the A320 family, and perhaps it's in my head, but I tend to notice it more on those aircraft than any other.
Kimberlyrj From United Kingdom, joined Mar 2008, 385 posts, RR: 1 Reply 12, posted (4 years 8 months 1 week 2 days 6 hours ago) and read 6792 times:
Hi there
Quoting USAIRWAYS321 (Reply 11): The buzzsaw is one of my favorite sounds. I first noticed it on the A320 family, and perhaps it's in my head, but I tend to notice it more on those aircraft than any other
I love it to, sounds great. I also noticed a very odd sound while working on a B772 GE version. On approach it makes so great buzzsaw / lawnmower. The RR version does not seem to do this, but makes a great growl sound on take off, its GREAT!
Access-Air From United States of America, joined Sep 2000, 1939 posts, RR: 15 Reply 13, posted (4 years 8 months 1 week 1 day 6 hours ago) and read 6603 times:
I have heard this Buzz Saw sound on many jets too and including the BAC OneEleven!! I have audio recorded a couple BAC fligts in the area of the engine inlet and you could definately hear it. Also a few flights on DC9s of all sizes and engine marks. Too and including 737-200s and 727-100/200.....Taped the sounds of a flight on an TWA 7272-231 back in 1987 from KCMO to STL and I was in seat 29F with an engine outside my window..Talk about a nice Pratt And Whitney song....You can also hear that buzz in a tape I made taking off in an AA DC10 out of Las Vegas....Some engines you cannot detect it because of all the sound suppression on the inlet. The Fokker 70/100 can be heard loud and clear.
The Buzz Saw sound would probably be much louder if it was not shrouded...Can you imagine the noise of one of those high bypass engines if the front fan was exposed? If you shrouded a prop on a prop plane and ducted it I can gurantee itd sound different just the same.
Have any of you heard the shriek made by the Good Ole C-5 Galaxy? Correct me if I am wrong, but back in the day, wasnt that just about how loud the first 747 engines used to be? Especially with their blow in doors?
Okay, I just thought Id throw in my 2 cents worth...
AA737-823 From United States of America, joined Mar 2000, 5341 posts, RR: 11 Reply 14, posted (4 years 8 months 6 days 12 hours ago) and read 6417 times:
But it's true- the IAE V2500 engine is known for its very unique noise. And the CFM on the Airbus sounds strange, too. Sounds quite different from the similar engine on the 737s.
747fan From United States of America, joined Jun 2007, 1165 posts, RR: 1 Reply 15, posted (4 years 8 months 6 days 10 hours ago) and read 6407 times:
I love that sound, its noticeable on almost all turbofan-powered aircraft, even low-bypass ones such as the PW JT8D and RR Spey (and even the PW JT15 on the Cessna Citation).
One of the best examples of this buzzsaw sound is that made by the RB211's on the 757:
EGNR From United Kingdom, joined Feb 2004, 503 posts, RR: 0 Reply 19, posted (4 years 8 months 6 days 1 hour ago) and read 6314 times:
From spotting at MAN, my perception is that the best aircraft for this buzzsaw noise is the RR-powered B757.
It seems to be particularly prevalent on the more elderly B757s - when Air 2000 was re-branding to First Choice, a number of their older B752s were cycled out of the fleet for newer models. The older ones had a more obvious buzzsaw sound than the newer ones. Or at least that's my perception. Jet2 have at least one B752 with a very vocal buzzsaw sound!
FlyASAGuy2005 From United States of America, joined Sep 2007, 6520 posts, RR: 11 Reply 21, posted (4 years 8 months 5 days 21 hours ago) and read 6271 times:
Quoting 747fan (Reply 15): One of the best examples of this buzzsaw sound is that made by the RB211's on the 757:
Quoting EGNR (Reply 19): It seems to be particularly prevalent on the more elderly B757s - when Air 2000 was re-branding to First Choice, a number of their older B752s were cycled out of the fleet for newer models. The older ones had a more obvious buzzsaw sound than the newer ones. Or at least that's my perception. Jet2 have at least one B752 with a very vocal buzzsaw sound!
I dn't know that it is with the 757. I've heard it on the T7 and 767 but it always sounded even "sweeter" on the 75.
Side note that kind of has nothing to do with this, but has anyone ever stood on the ramp or atleast near a CRJ and hear those engines scream (I hope this is a better example than wang )when they are spooled up for taxi or on take-off? It's the best sounding engine during that time IMO...
CAM2:"Lightning coming out of that one." CAM1: "What?"
Tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80 Reply 22, posted (4 years 8 months 5 days 18 hours ago) and read 6249 times:
Quoting Phxplanes (Reply 16): I thought the blades could not go supersonic because they would loose a lot of efficiency from the turbulent air flow.
Turbulence isn't the problem (I suspect most blades have turbulent boundary layers most of the time), it's shock waves that are the issue when you go supersonic. However, as previously noted, it's a local phenomenon that isn't affecting most of the fan.
Going locally supersonic isn't a death sentence or anything...the airflow on the upper side of the wing is also locally supersonic at cruise conditions for most commercial jets.
the CRJ spool up is a very nice sound, esp the UAX (skywest) taxiing out on one engine. in my station the rest of the CRJ is 200s and the pilots seem to just nudge off the stand, very little spooling.
Cc2314 From Ireland, joined Jan 2008, 149 posts, RR: 0 Reply 24, posted (4 years 8 months 2 days 10 hours ago) and read 6008 times:
I was crew onboard a L1011 (euro atlantic airways) i had a cockpit seat on a leg fron snn -dub,instead of staying in the cockpit i opted to go sit in the seat that was closest to the engine,,the growl from them RR on take off is unreal!!!
Luv2cattlecall From United States of America, joined Sep 2007, 1648 posts, RR: 2 Reply 25, posted (4 years 7 months 3 weeks 5 days 22 hours ago) and read 5736 times:
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)when they are spooled up for taxi or on take-off? It's the best sounding engine during that time IMO...
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