"We have identified three critical research areas: air-breathing propulsion, materials and structures, and boundary layer control," said James Pittman, principal investigator for NASA's Fundamental Aeronautics Program's Hypersonics Project at NASA's Langley Research Center in Hampton, Virginia. "These three areas are the biggest hurdles to successful hypersonic flight and low-cost space access using an air-breathing engine."
Satnews Daily
September 23rd, 2008
NASA and USAF In Hypersonic Race to Answers
"We have identified three critical research areas: air-breathing propulsion, materials and structures, and boundary layer control," said James Pittman, principal investigator for NASA's Fundamental Aeronautics Program's Hypersonics Project at NASA's Langley Research Center in Hampton, Virginia. "These three areas are the biggest hurdles to successful hypersonic flight and low-cost space access using an air-breathing engine."

