Sponsor Message:
Civil Aviation Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Rolls Royce Introduces New Quiet 777 Engine  
User currently offlineUal747 From , joined Dec 1969, posts, RR:
Posted (12 years 7 months 6 days 11 hours ago) and read 3930 times:



SEATTLE, Nov. 20, 2001 -- Boeing Commercial Airplanes and Rolls-Royce Aero Engines have completed a noise reduction flight test program that promises to make quiet jets even quieter.

Known as the Quiet Technology Demonstrator (QTD), a Rolls Royce Trent 800 engine was modified with a package of noise reduction technologies developed collaboratively by the two aerospace companies. Using a 777-200ER, the three week flight-test demonstrated noise levels significantly below those of a standard 777, which is known as one of the quietest airplanes in service today. Takeoff jet exhaust noise was reduced by up to four decibels and inlet fan noise was reduced by up to 13 decibels.

Engineers used saw-tooth-shaped aerodynamic devices at the rear of the nacelle and on the exhaust nozzle to control the mixing of the hot jet exhaust, the bypass stream and the ambient air. The shape of the devices was determined by computational fluid dynamics modeling and verified in wind tunnel tests using scale models.

Fan noise also was reduced with extensive acoustic improvements to the redesigned engine nacelle inlet. A new technology called Amax (area maximization) increased by 30 percent the area of acoustic treatment in the inlet casing. A new lining design was used that reduces objectionable "buzz saw" noise passengers often hear during takeoff and climb.

The flight tests, conducted at Boeing's Glasgow, Mont., airfield, verified the computer and laboratory results. Some 200 microphones were placed on the ground along the flight path, and 100 microphones were affixed to the 777. Teamed with computers, the microphones became an "acoustic camera" that accurately and dynamically pinpointed high-frequency noise sources on the airplane as it took off, flew the flight test pattern and landed again. This ground noise monitoring capability was made possible by NASA sponsorship.

Although the purpose of the QTD program was to reduce noise heard on the ground, levels within the cabin -- equally important to the airlines - also were analyzed. Nearly 100 microphones placed along the entire length of the cabin registered a reduction of forward cabin buzz-saw noise by seven decibels.

The culmination of years of work, these successful tests mark one of the final stages before QTD noise reduction technology is implemented in service. Combined with airframe noise reduction and engine redesign efforts being pursued separately, the new technologies can be incorporated on a new airplane program or as a retrofit to airplanes in service.


Looks kinda strange if you ask me.

UAL747


13 replies: All unread, jump to last
 
User currently offlineUal747 From , joined Dec 1969, posts, RR:
Reply 1, posted (12 years 7 months 6 days 11 hours ago) and read 3808 times:



User currently offlineHkgspotter1 From Hong Kong, joined Nov 2005, 0 posts, RR: 0
Reply 2, posted (12 years 7 months 6 days 11 hours ago) and read 3790 times:

It looks.....eerh nice but does it work ??. 777 dont even make much noise.

Also which aircraft is this being tested on ??. It can be the test 777 at it's B-HNL with CX.


User currently offlineDynkrisolo From United States of America, joined Feb 2001, 1857 posts, RR: 8
Reply 3, posted (12 years 7 months 6 days 11 hours ago) and read 3774 times:

I believe it is a B777 to be delivered to AA.

User currently offlineVafi88 From United States of America, joined Apr 2001, 3116 posts, RR: 17
Reply 4, posted (12 years 7 months 6 days 11 hours ago) and read 3760 times:

That looks cool! it has the squigly things on it!


I'd like to elect a president that has a Higher IQ than a retarted ant.
User currently offlineBa777-236 From Canada, joined Oct 2001, 673 posts, RR: 4
Reply 5, posted (12 years 7 months 6 days 11 hours ago) and read 3739 times:

Any idea on why Boeing chose the B777 (one of it's quietest planes) for this test?

Ba777-236



I like British Airways! I'm not sure why, but I do! ;-)
User currently offlineHkgspotter1 From Hong Kong, joined Nov 2005, 0 posts, RR: 0
Reply 6, posted (12 years 7 months 6 days 11 hours ago) and read 3727 times:

Thats what I mean, they dont make any noise. I see the CO 772 depart HKG for NYC and that is almost silent !!

User currently offlineMax Q From United States of America, joined May 2001, 4351 posts, RR: 19
Reply 7, posted (12 years 7 months 6 days 11 hours ago) and read 3700 times:

This modification could be a big advantage for airlines
seeking departure and arrival times at unpopular hours at noise sensitive airports.

Not to mention the good PR resulting from being more
'environmentally friendly'

And one day stage 4 noise limits will be a reality.



The best contribution to safety is a competent Pilot.
User currently offlineRayChuang From United States of America, joined Jun 2000, 7985 posts, RR: 5
Reply 8, posted (12 years 7 months 6 days 10 hours ago) and read 3677 times:

My guess is that this new engine nacelle breakthrough is just the thing to make new airplanes compliant with the toughest noise-emission standard for airplanes in the world--LHR's so-called QC2 standard.

Rolls-Royce might apply this to the nacelle of the Trent 900's that will be installed on the A380-800, that's to be sure.


User currently offlineBH346 From United States of America, joined Jan 2000, 3265 posts, RR: 14
Reply 9, posted (12 years 7 months 6 days 10 hours ago) and read 3669 times:

I hear the 777 is a bit noisy. Is this true?


Northwest Airlines - Some People Just Know How to Fly
User currently offlineMr.BA From Singapore, joined Sep 2000, 3423 posts, RR: 22
Reply 10, posted (12 years 7 months 6 days 10 hours ago) and read 3656 times:

I find the B777 is a bit noiser in the inside but it is really quiet on the outside.

alvin



Boeing747 万岁!
User currently offlineAWspicious From , joined Dec 1969, posts, RR:
Reply 11, posted (12 years 7 months 6 days 8 hours ago) and read 3628 times:

Reminds me of a cookie cutter  Smile/happy/getting dizzy
I assume they used the 777 as a test platform because it represents the cutting edge of civil aviation technology. (pardon the pun) They took one their most advanced engines and tried to make it even better. Push the envelope, if you will.
Perhaps, they felt it was better to demonstrate their ability to improve on technology that was designed for tomorrow than on technology that's almost past it's time.


User currently offlineFLY777UAL From United States of America, joined May 1999, 4512 posts, RR: 3
Reply 12, posted (12 years 7 months 6 days 6 hours ago) and read 3555 times:

It'll be great, especially with cutting down on the noise forward of door 2! It's horrible up there w/o headsets on!

F L Y 7 7 7 U A L


User currently offlineHkg_clk From Hong Kong, joined Jan 2001, 999 posts, RR: 2
Reply 13, posted (12 years 7 months 6 days 5 hours ago) and read 3539 times:

That saw-tooth shape nacelle looks cool!! I guess they're testing it on the 777 as it has the longest production cycle remaining and will therefore have to comply with many new regulations in the future.

I thought some manufacturers were going to use noise cancellation technology at one point? Did it not work?



See my homepage for a comprehensive guide to spotting and photography at HKG
Top Of Page
Forum Index

This topic is archived and can not be replied to any more.

Printer friendly format

Similar topics:More similar topics...
Boeing, Air New Zealand And Rolls-Royce Announce B posted Mon Oct 1 2007 15:07:10 by Dougbr2006
Airbus A350 Engine Rolls Royce Deal posted Fri Jul 7 2006 19:16:13 by Keesje
BA 777 Rolls Royce Vs GE90 posted Fri Jun 16 2006 06:44:21 by DFW13L
Trent Rolls-Royce Engine Video! posted Tue Mar 7 2006 18:55:26 by BoeingFever777
Rolls-Royce Completes Test Run Of New Trent 1000 posted Tue Feb 14 2006 19:17:38 by Leelaw
Rolls-Royce May Build U.S. Engine Plant posted Tue Nov 8 2005 23:23:20 by BoomBoom
Rolls-Royce Likely To Win MAS A380 Engine Contract posted Thu Nov 4 2004 16:32:10 by Joule
New Rolls Royce Orders? posted Wed Jun 2 2004 16:07:25 by CHRISBA777ER
What Plane Use Rolls Royce Jet Engine?(Fire Truck) posted Tue Aug 20 2002 05:19:24 by Bobcat
Rolls Royce To Open Engine Overhaul Facility @ SIN posted Tue Feb 5 2002 08:51:18 by Singapore_Air