Aerion has enlarged the cabin of its supersonic business jet as it continues to fine tune the design in a bid to reassure potential manufacturing partners that the aircraft will achieve its weight and performance targets.
Reno, Nevada-based Aerion says it is refining the design and business case in an effort to present manufacturers with "a profitable programme that can move swiftly into full-scale engineering and prototype development".
An investor group headed by billionaire Robert Bass is funding initial design and planning while Aerion looks for industrial and financial partners to bear the $2 billion cost of development, which is expected to take five years.
Citing interest from fleet operators, including fractional ownership and aircraft management companies, Aerion says it has held discussions with a number of manufacturers.
"The interest is there," says chief financial officer James Stewart. "Manufacturers must weigh the Aerion against other ongoing of anticipated programmes."
Meanwhile the forward fuselage has been reshaped to increase cabin height and width and improve the cockpit and windshield design.
The aft fuselage has been stretched and the tail shrunk to improve take-off performance and reduce weight and cruise drag.
Electrical and pneumatic system architectures have been studied in conjunction with United Technologies, while fuel system layout and sizing has been performed by Argo-Tech under contract to Aerion.
Engine reliability, operability and noise have been studied with Pratt & Whitney, manufacturer of the aircraft's JT8D-219 turbofans, and Aerion says the inlet and nozzle designs are ready for a series of subscale noise and performance validation tests.
Aerion has still to decide how to validate the design tools developed to predict the extent of supersonic natural laminar flow achieved in flight, and critical to meeting the performance targets.
The company conducted supersonic rocket-sled tests last year, but encountered problems (Flight International, 17-23 October 2006).
Supersonic flight tests of a small wing section under a NASA Boeing F-15 in 1999 demonstrated full-chord laminar flow, but Aerion needs a larger-scale test to confirm its performance predictions.
Alternatives include tests in a high-pressure transonic windtunnel and flight testing of a larger wing section, but these have limitations. Aerion, meanwhile, is to continue exploratory rocket-sled tests at Sandia National Laboratories in New Mexico.