NASA awarded the University of Miami a $100,000 grant to continue development of a supersonic bi-directional flying wing (SBiDir-FW) aircraft. Besides looking completely futuristic with its four-pointed star design, the concept plane will be able to rotate in mid air and transition between broad-wing subsonic and shorter wingspan supersonic configurations.
Zha explains that aircraft design is usually a compromise between subsonic and supersonic performance. At lower speeds the broad wings give more lift and minimize takeoff distance whereas swept back wings with a smaller profile enhance performance at higher speeds. The bi-directional flying wing tackles the subsonic v. supersonic problem by orienting itself at takeoff on the broader wings then rotating 90 degrees in flight to transition to its high-speed, shorter wing span mode. “Such rotation allows the SBIDIR-FW to achieve superior performance at both supersonic and subsonic speeds,” he says.
The team’s goal is to create an environmentally friendly and economically viable airplane for supersonic civil transport within 30 years. To aid that, they are using a mix of aluminum, titanium, stainless steel and composite materials to make it lightweight and more durable. Up for consideration are graphite, aramid, boron and fiberglass composites. “Graphite is the most popular material for primary structures and fiberglass is generally used for secondary structures,” syas Zha. “Because composites cost more than metal alloys a combination of materials including various composites and metal alloys must be used to satisfy performance and cost concerns. For example, a graphite-epoxy composite can be used for the highest temperature areas, but it costs 20 times more than aluminum. As a result, metal alloys should be used for areas where the conditions do not require composites.” [Gizmag]
Melinda Skea is ACMA’s assistant director of communications.