MIT helping to build a jet that could be quiet as a car
But aircraft probably won't fly before 2030
Now here's a jet even East Boston can love.
Researchers from the Massachusetts Institute of Technology and Cambridge University in England, after three years of work, are set to unveil the design for a virtually silent passenger jet in London today . Not only would the 215-person jet be roughly as quiet as car, it would get better mileage: It would carry people 124 miles per gallon of fuel, 3 percent better than today's Toyota Prius hybrid carrying two passengers.
One big hitch: Researchers don't expect a working model of the so-called silent aircraft to take off until 2030. That means decades more rattled plates and earaches for residents of long-suffering communities like East Boston, home to Logan International Airport.
The plane is the work of a 40-person Silent Aircraft Initiative, led by MIT aeronautics professor Edward M. Greitzer and Cambridge professor Ann P. Dowling. They've been supported by over 30 big aviation suppliers, including top aircraft manufacturer Boeing Co. and jet engine maker Rolls-Royce PLC . The design is being unveiled at the Royal Aeronautical Society this morning.
The most dramatic feature: Someone standing on the street outside an airport would hear just 69 decibels of sound. Normal conversation is typically described by scientists as being at 60 decibels, street traffic at 70, and a vacuum cleaner at 80. On the streets of East Boston or Winthrop, the plane would be no louder than passing traffic.
Three major innovations that would make the plane so quiet are:
"There are a lot of technical and economic issues that have to be worked out, but I hope this work has some impacts in the nearer term, in terms of the designs of airplanes that come out between now and then," Greitzer said. A team led by project chief engineers Zoltan S. Spakovszky, another MIT professor, and MIT research engineer James I. Hileman will still have years of work, Greitzer said, to translate the concepts into a working prototype.
Whether the MIT-Cambridge work could really lead to a quieter version of, say, a Boeing 757 is unclear. Boeing spokeswoman Debbie Nomaguchi noted that the design "is really optimized for eliminating noise." But Boeing -- which has received orders for 775 jets worldwide so far this year -- has to deal with much more mundane issues. "For the airlines, is this going to be economical for them to operate? Is it going to be reliable? For the passengers, is it going to be comfortable? There are just a vast number of requirements that we have to address," she said.
But, she added, the MIT Silent Plane "presents some very interesting ideas. It helps stretch our imagination."
Peter J. Howe can be reached at howe@globe.com. 
