Information technology (IT), environmental concerns and global competitiveness will stimulate major changes in aerospace, says Dennis Bushnell, NASA's chief scientist at the Langley Research Center, Virginia.
Speaking at the Royal Aeronautical Society in London, Bushnell envisaged a future including "dramatically improved air transports, automatic VTOL aircraft for personal use, and revolutionary space access".
His ideas included strut-braced wings with wingtip engines; fuel cells; blended-wing bodies; advanced rockets and "airbreathers" for space access.
IT developments would reduce conventional travel, but would enhance air vehicle affordability, productivity and performance, including automatic or robotic flight, said Bushnell.
Strut-braced wings reduce wing thickness and sweep, improving low-drag laminar flow and increasing span, reducing wing chord, improving airfield performance and reducing vortex hazards, he said. Bushnell added that wingtip-mounted engines could overcome drag arising from limiting span (to fit airport ramps), and that thrust vectoring could accommodate the engine-out case.
A propulsion cycle such as a lithium-air fuel cell would allow pollution to be "captured" for storage and subsequent disposal on the ground, solving CO2 and NOx problems, said Bushnell.
Thrust would come from electrically-driven ducted fans, whose weight would be offset by advantages such as very low emissions, improved energy conversion, lower noise/vibration and longer engine life.
"Blended-wing bodies (BWBs) offer large increases in lift/drag ratios, lower weight and a surfeit of internal volume, and are highly conducive to enhanced range, cargo operation and passenger comfort. The challenges and opportunities of an 800 plus-passenger BWB are tremendous, but evidently workable."
Source: Flight International
