There was only one other customer for the 805-23. In 1961, Sud Aviation approached GE to pitch them on the idea of adapting the Rolls-Royce Avon powered Caravelle to the 805-23, producing a flying technology showcase for both companies. For this role they introduced a new version with a relatively short fan cowl and thrust reverser, compared to the full-length cowling on the 990. Rolls-Royce quickly built and tested an aft-fan demonstrator Avon to compete with the greater thrust and lower specific fuel consumption of the CJ805-23. In the end, the Caravelle was instead re-engined with the P&W JT8D turbofan.