I find it rather odd that they are using a 43 year old engine on a supersonic jet. The JT8D first flew in in64.

PICTURE: Aerion refines supersonic business jet design
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.

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).

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