Memo from Mr Slatter to Mr Lindsey: Notes on a visit to Hawker's at Dunsfold re....

Discussion of criticism of the Sapphires: Mr Duke, Hawkers, said that on some occasions during starting, the engine speed dropped slightly after reaching 1800 or 2000 rpm before again accelerating. This suggests that the starter panel cut-out is set too high and that the starting spill valve electrical system in the aircraft may not always operte correctly and we asked Hawkers to check these points. Governor stability and creep and jet pip temperature limitations: Mr Duke emphasised the difficulty of operating the engine at high performance at altitude. he also pointed out that, because we had set down for take-off rpm on the ground to alleviate the creep trouble now occuring at high pipe temperature was still present despite the fact the engine had been derated by removing two segments from the nozzle