Ever since the first supersonic flight in 1947, there’s been a lot of commercial interest in supersonic aircraft. If made affordable, such a plane flying at Mach 1.5 (one and a half times the speed of sound) could take a person from Newark, New Jersey to Singapore (currently the longest available commercial flight) in under 9 hours. This may not sound like much, but the flight currently takes 18 hours.
Unfortunately, multiple major problems have thwarted previous efforts to make supersonic flight available to the public. While one supersonic airliner, the Concord, was flown for a short period, it quickly experienced these problems. First, flying at speeds past above Mach 1 leads to something called “wave drag”, which is a strong force resulting from the pressure of sonic shock waves on the airplane. In simple terms, wave drag makes it much harder to fly, and supersonic vehicles need enormous amounts of fuel to overcome this barrier. Not only does this make the operation costly, it leads to environmental concerns as well. In addition to wave drag, going supersonic means producing the well known sonic boom. Sonic booms are a result of the same shock waves that cause wave drag, and they follow an airplane for its entire flight, creating a very loud wake called the sonic carpet. Not only does this explosion-like phenomenon annoy people in residential communities around airports, it can actually cause physical damage to property and terrify animals. For these reasons, the notion of commercial supersonic flight was essentially abandoned in the early 2000’s, when the Concord was retired.
Since then, the notion of low-boom aircraft has become popular with those who are still enamored with the notion of supersonic flight despite its initial failure. Several companies, including Lockheed Martin and Boom Technology, have been working on low-boom fuselage and wing designs. Multiple changes to the aircraft design allow for drastically reduced sonic booms- Lockheed Martin claims that its new X-59 QueSST makes a noise that sounds less like a boom and more like a quiet thump. Sleek body designs minimize the amount of air getting slammed into by the plane, which means less colliding particles and less shock. Swept back wings keep the wings inside of an area called the Mach cone, which is the space behind the pressure wave created by the plane. The air in this space has already slowed down due collisions with the plane and isn’t moving at sonic speeds anymore. In addition, special “LFC” wing designs can help the flow over the wings stay smooth, eliminating shocks along the wing edges.
Some companies are trying even crazier and cooler methods to reduce wave drag. A company called HyperMach is pioneering technology that will release plasma in front of the jet, then re-ionize it at the back end. This would create a low-drag shield around the plane, virtually eliminating mach drag and shock waves and allowing HyperMach’s supersonic aircraft, the Sonic Star, to fly at speeds of Mach 5 and above with none of the typical negative effects of high speed flight.
As the world economy becomes increasingly interconnected, the need for faster and more efficient travel is becoming greater. The low-boom, high efficiency planes of tomorrow will be able to take people across the world and back in mere hours, minus the shock waves and massive fuel costs of older designs.
On the Horizon 