A MUCH Quieter Flight May Not Be Far Away
If you've ever tried to
catch a nap on a loud airliner, but are one of those people who
don't find the low rumbling of rushing air and guzzling turbofans
particularly soothing, NASA may have some welcome news for you.
The agency, working with three corporations, have completed
flight tests of a special B777 designed to help quiet jet aircraft
noise, both in the passenger cabin and on the ground.
The program was a cooperative effort by NASA, The Boeing
Company, the Goodrich Corp., and GE Transportation Aircraft
Engines. Japan's All Nippon Airways provided the testbed
"The team was pleased to see that concepts we had developed with
computer simulations and in wind tunnels worked on a real
airplane," said Charlotte Whitfield, NASA's Quiet Aircraft
Technology manager of airframe system noise reduction.
During the three week test program, the 777 was fitted with
various noise reduction combinations, including a variety of
landing gear and engine inlet-exhaust combinations.
Some new exhaust configurations achieved as much as a
two-decibel improvement in noise. In addition, the common low
frequency "rumble" heard in the aft cabin by passengers at cruise
altitude was reduced by as much as four to six decibels.
Perhaps most encouraging, though, was a sound-absorbing engine
liner built by Goodrich. According to NASA, the seamless liner
reduced turbofan inlet noise heard in the front of the cabin by up
to 15 decibels -- making such sounds nearly inaudible.
Imagine a whisper-quiet cabin... that would allow you to hear
your seatmate talking on their cell phone that much more