New Supersonic Jet Flies 1100 MPH, Quietly
The Quiet SST is the first in a new generation of X-Planes that will fly faster and use less fuel than existing aircraft.
Technology moves faster every day. But commercial air travel hasn't changed as quickly as some industries in recent years. Experts project big changes in the next few decades, though, especially as aviation companies deploy significant innovations in design, material sciences and alternative energy sources. Here we take a look at some of changes on the horizon for commercial, cargo and experimental aircraft.
The N3-X concept aircraft, from Boeing and NASA, is based on a blended wing body (BWB) design intended to improve aerodynamics, fuel efficiency and noise emissions. The ultra-wide fuselage would greatly expand carrying capacity for commercial flights.
NASA/MIT/Aurora Flight Sciences
Developed by a research team from the Massachusetts Institute of Technology (MIT), the D8 "Double Bubble" aircraft would be used for domestic flights and is designed to fly at Mach 0.74 carrying 180 passengers in a coach cabin roomier than that of a Boeing 737-800. The D8 could enter service as soon as 2030, NASA says.
From Lockheed Martin, this concept design for a future supersonic aircraft is focused on reducing emissions and creating a quieter boom. A quieter craft would allow supersonic flights over land, where they are currently prohibited.
Meanwhile, over on the cargo plane tarmac, the GIGAbay concept envisions a ginormous aircraft powered by four hybrid fuel/electric engines, with supplemental energy provided by hydrogen fuel cells, wind generators and solar panels. The cargo area of the GIGAbay design is so large it could carry other jumbo aircraft, or even mobile field hospitals.
Powered by two superconducting electric motors, the concept plane known as the VoltAir (get it?) is a proposed all-electric airliner out of Europe. The engines would draw from next-generation lithium ion batteries -- really big ones -- that would be simply swapped out between flights.
University of Pisa, Italy
Some cutting-edge technologies on the horizon are actually modifications of existing designs that have been around for more than a century. To wit, the illustration above imagines the closed-wing "PrandtlPlane" design applied to commercial passenger aircraft. Closed-wing planes have smaller wingspans than traditional aircraft, relative to fuselage size, allowing larger planes to operate out of smaller airports.
Another sort of hybrid, the E-Thrust design -- from Rolls-Royce and several European partners -- uses a combination of gas-turbine engines and battery-powered fans. The jet engines would only kick in when needed, similar to gas/electric hybrid cars. The fans would also be used, on descent, as built-in windmills to recharge the onboard batteries.
And from the ultralight division, we have the Solar Impulse 2, the latest iteration of the world's most advanced solar-powered, single-seat aircraft. The Swiss team behind the project plans to circumnavigate the planet in 2015, using a team of pilots flying in shifts over the course of about five months.
Finally, from the designer who brought us the GIGAbay cargo plane, the mighty Sky Whale also subscribes to the concept that bigger equals better -- and greener. The Sky Whale is a largely theoretical vision for a passenger plane that could seat 755 passengers on three floors, using a combination of alternative power sources. The upshot? More passengers per flight means fewer flights, and fewer emissions.
Call it an old idea in a new box. NASA engineers are working on a Concorde-like commercial airplane that doesn't produce the bone-jarring sonic booms that helped derail the original Concorde, which made its last flight in 2003.
A $20 million design contract for the QueSST -- for Quiet SST -- was awarded to Lockheed Martin at a Monday press conference at Reagan National Airport in Washington, DC.
At the conference, NASA Administrator Charles Bolden said the QueSST, a new generation of “X-Plane," will create “a soft thump.”
It will climb to about 50,000 feet cruising altitude, more than 10,000 feet higher than most commercial aircraft, and produce 20 times less sound energy than the Concorde.
It will also fly faster, use less fuel and land more quietly than existing aircraft.
“We believe we will make flying a lot more enjoyable,” Bolden said.
Bolden also said the new aircraft will use half as much fuel as current planes and emit fewer greenhouse gases. Some advances will come in reduced flying times -- a faster plane pollutes less as long as it’s not a gas-guzzler. Lighter, more aerodynamic airplane bodies help make this happen.
As for silencing the sonic boom, NASA aeronautic engineers are working on a special shape that will prevent the build up of pressure waves along the airplane fuselage, explained Peter Coen, supersonic project manager at NASA Langley.
When any aircraft travels faster than sound, pressure waves caused by the build-up of air around the plane’s nose, canopy and other structures all produce individual shockwaves, which then combine into two waves by the time they reach the ground, Coen said. That’s why we hear a double-boom when military aircraft fly overhead.
The Quiet SST is the first in a new generation of X-Planes that will fly faster and use less fuel than existing aircraft.NASA
NASA says it has figured out how to turn a sonic boom into “the sound of a car door closing down the street,” Coen said.
“We concentrate very carefully on the shape of the aircraft, everything from the forward fuselage, the shape of the wings, and the engine is positioned with the (air intake) inlet on top,” he said. “We want to control the strength and position of every shockwave that is formed. If we can keep them the same strength and apart from each other, they will never coalesce.”
Coen said NASA has already reduced the sound of the shock wave down to a 75 perceived level decibels. That compares to the 105 perceived level dB generated by the Concorde during its heyday.
NASA’s announcement Monday was the design phase a single-pilot demonstrator plane that will eventually cost $300 million to build and test, but could be flying as soon as 2019.
The demonstrator will use an existing F-18 jet engine to reach 1,100 miles per hour, or Mach 1.4. For comparison, the Concorde had an average cruising speed of Mach 2.02 (1,334 mph) or just over twice the speed of sound. But the new QueSST is no slouch. It'll fly passengers just about anywhere in world in six hours or less.
The Concorde made its public debut in 1969, and was flown up by several airlines including British Airways and Air France. A competing American version called the Boeing 2707 SST was canceled before being built over potential environmental and noise concerns.
Concorde made its final flight in 2003, and was bested by huge fuel costs, ticket prices and the problem that it could not fly over land at night because of complaints from the shock wave.
NASA’s QueSST project is part of a larger $3.7 billion New Horizons in Aviation initiative included in NASA’s 2017 fiscal year budget request. The larger package must still be approved by Congress.