Archives




View Full Version : Quiet Jetliners Would Also Save Fuel.


Chuck
11-09-2006, 08:29 AM
MIT, Cambridge researchers to unveil redesigned airliner Monday. (http://www.cnn.com/2006/TECH/11/06/silent.aircraft.ap/index.html)

CNN - Nov. 8, 2006

http://www.cleanmpg.com/photos/data/501/silentjet.jpgBOSTON, Massachusetts - A U.S.-British team of researchers from academia and the aerospace industry believes the passenger aircraft of the distant future will not only be fuel efficient, but virtually silent.

Leaders of a long-range research venture called the "Silent Aircraft Initiative" were scheduled Monday to release a conceptual design for a plane they say could cut through the air with practically no sound bothering those below, thanks to its unique shape and design features to limit engine noise.

The design adds a new twist to aviation's long history of mixed success developing flying wings designed to be more fuel-and space-efficient than conventional aircraft with long, narrow fuselages.

The design, to be announced in a news conference at the Royal Aeronautical Society in London, would blend fuselage and wings together so that the entire airframe provides lift -- an approach that to date has been confined largely to payload-carrying military aircraft such as long-range bombers.

The body shape of the "silent aircraft" would allow for a slower landing approach and takeoff to cut airport noise -- a form of environmental pollution that makes it politically unpopular to expand airports and flight schedules.

"The 'silent aircraft' can help address this concern and thus aid in meeting the increasing passenger demand for air transport," said Edward Greitzer, and professor of aeronautics at the Massachusetts Institute of Technology.

Even if he's right, don't expect to see -- or hear -- such a plane anytime soon. The project is aimed at establishing research knowledge that could lead to development of an aircraft by 2030. And whether such a plane could become a commercial success is anybody's guess.

But the project, led by researchers at Cambridge, Massachusetts-based MIT and Cambridge University in England, has plenty of commercial interest so far. The two universities say more than 30 aviation companies from around the world participated in the design, including aircraft maker Boeing Co. and engine maker Rolls-Royce PLC.

Rolls-Royce wouldn't participate if the project didn't have potential to help shape future aircraft design, said Martin Brodie, a spokesman for the London-based company.

"We have a very strong record of involvement in environmental programs anyway, so this is just a logical thing for us to get involved in," Brodie said. "This is really a clear-blue-sky thing for the moment, and we'll have to wait to see what develops."

More than 40 researchers from MIT and Cambridge as well as engineers from the 30 companies have been collaborating on the design since the project's launch three years ago. Funding has come largely from the British government's Department of Trade and Industry, which committed money seven years ago to establish the Cambridge-MIT Institute, a joint venture between the schools that also has worked on other projects.

For now, the aviation project's goal is not to produce a marketable aircraft.

"The goal was to find out what technologies would be required, and what an aircraft would look like if a step-change in noise reduction was one of the key drivers for design," said Zoltan Spakovszky, an MIT aeronautics professor and a chief engineer on the project.

One aspect of the plane's sound-reducing design eliminates flaps -- hinged sections on the rear of each wing -- to reduce a major source of noise as the plane cuts through the air at takeoff and landing.

To reduce sound reaching the ground, the jet engines would be embedded into the plane's body, rather than hung from the wings as on conventional airliners. The engines would have variable-size jet nozzles, allowing slower jet propulsion during takeoff and landing but efficient cruising at higher speeds.

The proposed plane is designed to carry 215 passengers and achieve fuel efficiency of 124 passenger-miles per gallon.

By comparison, Boeing's 787 Dreamliner, a fuel-efficient airliner due for delivery in 2008, is expected to achieve 100 passenger-miles per gallon on a typical flight, Boeing spokesman Adam Morgan said.

Chuck
11-09-2006, 08:34 AM
For a detail of how the silent jetliner is quieter and saves more fuel, please see this BBC article (http://news.bbc.co.uk/2/hi/technology/6120132.stm). (excellent)

Boeing must have used their research on the Sonic Cruiser for the quiet jetliner. Check out the article and picture to see how much the Sonic Curiser looks like the quiet jetliner (http://en.wikipedia.org/wiki/Boeing_787).

The Sonic Cruiser was the early prototype of the Boeing 787 Dreamliner. Wish they could have gone with a design like this, but Boeing was fighting for their life right after 9/11 and decided to go with a more conventional design. The Sonic Cruiser was intended to fly just under the sound barrier at Mach .95 and consume no more fuel than conventional planes flying at Mach .85.

hobbit
11-09-2006, 09:18 PM
Anyone know offhand what the butt-miles-per-gallon of a typical
airliner is right now these days? Last I dug up it was in the
neighborhood of 35, but those might have been older figures.
I *hope* I'm getting better than flying as a single-occupant
prius...
.
_H*

xcel
11-10-2006, 02:42 AM
Hi Hobbit:

___The last article I remember reading on this subject (some time ago mind you) showed a full passenger airliner receiving along the lines of 100 mpg per passenger equivalent. Nowadays, full is as close to reality as I have seen it by comparison to just 10 - 20 years ago so there may be some hope here?

___Good Luck

___Wayne

hobbit
11-10-2006, 12:48 PM
Hmm. Wikipedia weighs in at 49 as of 1998. Not that Wikipedia
is necessarily an "authority" on anything. Trains, of course,
have it far and away over almost all other forms of transportation
except perhaps the bicycle...
.
[from the Fuel_efficiency entry over there..]
.
_H*

HAFNHAF
11-10-2006, 09:45 PM
gee, that looks familiar..... Where have I seen that before??? Oh yeah, NOW I remember!

http://i123.photobucket.com/albums/o292/hafnhaf/BWBwithAndy25percent.jpg

And yes, thats my ugly mug.

Pravus Prime
11-12-2006, 07:05 AM
Hey, that's the Arkbird from Ace Combat 5 (Video game)!

Tochatihu
11-12-2006, 11:06 AM
Engines on pods - very nice, HAF. You have seen the HondaJet?

DAS

HAFNHAF
11-12-2006, 01:52 PM
maybe....

"Last year Honda R&D Americas, Inc., Greensboro, N.C., used the National Transonic Facility at NASA Langley to collect data for Honda engineers as they were designing the HondaJet."

:D

xcel
11-12-2006, 10:21 PM
Hi Andy:

___Do you have a cool job or what ;)

___Hobbit, I found a possible answer inside an article describing the same airliner advancements.

Team moves toward silent, eco-friendly plane (http://www.geekland.org/team-moves-toward-silent-eco-friendly-plane/)In a typical flight, the proposed plane, which is designed to carry 215 passengers, is predicted to achieve 124 passenger-miles per gallon, almost 25 percent more than current aircraft, according to Greitzer.

___100 mpg per passenger equivalent appears to be the ~ answer according to these guys as well?

___Good Luck

___Wayne

HAFNHAF
11-13-2006, 05:41 AM
yeah, very cool! -250 degrees F, actually. ;)

Chuck
11-13-2006, 07:52 AM
To the admins:

Would it be legal to post the savings in aviation fuel HAFNHALF has saved? :D

HAFNHAF
11-13-2006, 01:54 PM
now THAT would be a tough one to figure out! :)

hobbit
11-14-2006, 04:51 PM
Hmmm. Well, I guess I won't feel quite as smug driving
~ 3000 miles by myself in december, but it'll still be
cheaper and less hassle...
.
_H*



Copyright 2006 Clean MPG, LLC. All Rights Reserved.