Is Supersonic Airline Travel Making a Comeback?
See You In L.A. In 2 Hours. I’m Boarding At JFK Now!
Does New York to Los Angeles in two hours sound like science fiction? Not If a handful of ambitious aeronautical firms have their way! Forty-eight years after the Concorde was introduced and fourteen since it was taken out of transatlantic service, the race is on to put commercial supersonic jet aircraft back into the skies. This time it’s not just a race against time, it’s a race against conventional physics and maybe even conventional wisdom.
It’s a simple fact that for most air travelers, there haven’t been any real significant advances in the speed of airliners since the 1950s, when jets began replacing piston powered airliners. The exception has been for passengers who flew the supersonic Concorde. While the Concorde was both an extraordinary and idealistic innovation , it really wasn’t very practical as a mass transit vehicle.
Flying Faster Than The Speed Of Sound – Breaking Fiscal As Well As Physical Barriers.
Breaking through the speed of sound was achieved by the famous test pilot and WWII ace, Chuck Yeager, on October 14, 1947. That was 70 years ago! The consequence of breaking the sound barrier was the infamous sonic boom. A sonic boom is the result of shock waves generated by an airframe going from front and back and joining together in an “N” pattern that results in a loud bang. The sound is akin to a canon blast or a tremendous thunderclap.
Despite the Concorde’s dart-like aerodynamic shape, it still produced a sonic boom when traveling at supersonic speeds. It was that boom and the disturbance it caused to those on that ground, which prompted the FAA to prohibit overland flights across the continental U.S. by the Concorde – limiting its use to transoceanic flights.
Another limitation of the Concorde was cost – it was expensive to fly.
Both British Airways and Air France lost money during its first six years of operation. Profitability wasn’t achieved until market research proved the true value of supersonic travel was the time compression it afforded business travelers. Apparently, when time is money, business is more than willing to pay a premium price.
Because Concorde’s airframe needed to produce minimum drag, its passenger cabin was narrow and restricted, allowing it to carry only between 92 and 128 passengers. The limited space in combination with a wide delta wing and fuel thirsty Rolls Royce engines (equipped with afterburners) gave the aircraft around 17 miles to the gallon per passenger. That’s about 50 miles per gallon less per passenger than a conventional commercial airliner, but still within range of the operating costs of a business jet.
At its peak, a round-trip flight on Concorde from London to New York in the early 1990’s cost about $12,000. However, by the time Concorde was being phased out, round trip prices were discounted to around $7,000, and the supersonic air carriers were making profits even with half-empty aircrafts. In other words, they had found their market – business travelers who viewed the supersonic compression of time as money.
Old Problems, Perhaps Some New Solutions
Ever since the Concorde went out of service, aerospace companies, including Boeing or Airbus, have been endeavoring to create a viable supersonic transport that could solve the enduring problems of high fuel consumption and sonic booms. The difference now is that there have been significant advances in technology with computer modeling, composite materials and more efficient jet engines available to address these issues. These new technologies result in lighter, more aerodynamic airframe designs that lower manufacturing and operating costs. Given these technological advances, the question becomes less about how supersonic travel can be done and more about when and where it can be used successfully.
Let’s start with that sonic boom problem.
Over the years, NASA has devised new technologies that could mitigate sonic booms and reduce the decibel level created by a supersonic aircraft. The Concorde, for example, created a boom of about 135 decibels. That is louder than a gunshot (133dB) and close to the pain threshold (140dB). Through its X-Plane research, NASA is working to reduce those decibels down to just 70 decibels, which is lower than a propeller aircraft flying overhead at 1000 feet. It is still noisy, but not eardrum-shatteringly so.
In a 2016 Wired article, Juan Jose Alsonso, a professor of aeronautics at Stanford University stated, “the trick to making airplanes quiet is to change the way the air flows around the airplane.” Considering the professor worked on X-Plane designs for NASA, that would suggest a smoother, more drag-resistant airframe may be the solution, coupled with new engine technology.
A company starts-up with a “Boom”
A Colorado based-aeronautics company deliberately called “Boom” Technology, Inc. is more than betting it can produce a “boom” resistant airframe. In fact, they already have a 1/3 scale prototype which is set to be flight tested this year.
Blake Scholl, chief executive of Boom Technology Inc. told the L.A. Times that the aircraft will use medium-sized turbo fan jets, not unlike subsonic commercial airliners. He said the modifications will be made by major engine companies, but did not disclose the names of those companies. However, according to CNBC, GE, Honeywell, Tencate and Stratasys are among the companies working on the engine modifications. If Boom and its partners can achieve the modification to a conventional fan jet which Mr. Scholl suggests, the aircraft will make far less of a boom than any supersonic to date.
According to CNBC, Boom’s supersonic airframe “…comes with two configurations of either 55 business class seats or 15 business and 30 first-class seats for longer flights.” The price for London to New York would be about $5,000. Clearly the boom project is not directed at creating a business jet, but an airliner that caters to high-end business travelers. Boom promises to whisk these time-conscious travelers across the sky at Mach 2.2 or 1,452 miles an hour, which is about 100 miles an hour faster than Concorde.
Boom has certainly gotten the attention of serious players. Not only has it received manufacturing help from Richard Branson’s Virgin Galactic Space Co., but as of June of this year it has received orders from five airlines. Fox News recently reported the company has raised $33 million to achieve this goal – and the aircraft hasn’t even flown yet!
Boom is promising to have its Boom XB-1 Supersonic Demonstrator, nick-named “Baby Boom” aircraft in service by 2020.
Supersonic Is One Thing, Hypersonic Is Something Else
This brings us back to manufacturing giants Boeing and Airbus. Both want to maintain their dominance in commercial aircraft manufacturing. To achieve this goal, they must stay on the cutting edge of air travel, which means beyond where their top-of-the-fleet aircraft cruise now – roughly 560 miles an hour.
Given their histories, Boeing and Airbus aren’t going to sit on the sidelines while a start-up or two go supersonic. In fact, they’re more than likely want to go beyond supersonic to Mach 5 or better, which is hypersonic. Two years ago, Airbus was granted a U.S. patent for a hypersonic airliner with a delta wing design reminiscent of the Concorde. Airbus claims it could be capable of Mach 4.5 speed. The project has been dubbed Concorde 2 and its designers say the aircraft will climb vertically before breaking the sound barrier and then fly horizontally like any jet airliner. Boeing is already involved in hypersonic projects for the U.S. military having recently been awarded a U.S. military contract to build DARPA’s (Defense Advanced Research Project Agency) re-usable hypersonic XS-1 space vehicle.
Is FAA Ready To Lift Ban On Overland Supersonic Commercial Flights?
The answer is not yet, and certainly not until noise levels have been sufficiently reduced so as not to be a nuisance or danger to the public. NASA thinks the boom can be lowered (forgive the pun). Their plan is to fly a supersonic aircraft (designed by Lockheed Martin and powered by NASA’s reduced sonic boom engine technology) over populated areas to test public opinion to the reduced noise as early as 2018.
In the event the public and the FAA still reject overland supersonic flight, there is one last option. It’s called the Cygnus M3 – the brain child of UK-based aircraft design Tom Johnson. Mr. Johnson has invented a swing-wing which could be extended at subsonic speeds and retracted for supersonic operation.
The Cygnus 3 also provides longer range, something biz-jet owners and airlines are always looking for. The combination of subsonic and supersonic flight could very well push this concept forward if the FAA continues to prohibit supersonic flight over land.
When one of these companies and their technologies can overcome these supersonic hurtles, then supersonic transport will again be in our future. Keep looking to the skies and listening. It may very well be that what you don’t hear overhead could usher in a new era in air travel.