Although wings have received the most attention from shape-change researchers, "there are advantages to making changes in the propulsion system as well," says St. Louis-based Edward V. White of Boeing Phantom Works.
What's more, the advantages seem to apply to both military and civil aviation.
In a recently completed DARPA-funded study, White's
team demonstrated dynamic reconfiguring of engine-inlet nozzles of F-15 Eagle fighter aircraft that could boost the aircraft's range by up to 20 percent.
Now, the Boeing engineers are looking into subtle shape shifting of teeth, called chevrons, which intrude slightly into the exhaust nozzles of passenger jets to reduce engine noise on take-off.Unfortunately, the chevrons also reduce fuel efficiency.By making chevrons that would reshape themselves to withdraw from the flow after take off, aircraft makers could recoup a small but significant amount of fuel.
"It's something that would benefit just about all commercial aircraft," White
Break the mold
...Edward V. WhiteBoeing Phantom WorksP.O. Box 2515Seal Beach, CA 90740
From Science News
, Vol.164, No. 23, Dec. 6, 2003, p. 359.