Minutes of D.Eng.RD meeting held at Armstrong Siddeley Motors on 30 November 1955

Sapphire flight running time total of 10,612 hours. Sapphire development and future programme; Sa.7 Javelin Type test. Flying test beds: AST Lancaster VM.773 2 Sa.6 outboard; Canberra WK.141 (twin Sa.7); Canberra VW.787 (Twin S.a.6)an engine was rejected for excessive vibration; provisioning of Sa.7 Javelin aircraft. Prototype aircraft: HP Victor WV.775 (4 Sa.6); Avro Vulcan VX.770 (twin Sa.5) in first aircraft; English Electric P.1 WG.760 (twin Sa.5) first aircraft; English Electric P.1 WG.763 (twin Sa.5) 2nd aircraft; Javelin XA.560 (twin Sa.7). Viper 3 5 & 8 running times to date (from 1 April 1955) 1061 hours. Viper in tail of Mamba Lancaster SW.342 (V.5); Canberra WK.163 (Avon engines) Viper 3 (Long life fuel system); Provost XD.674 (V.5). Double Mamba problems: Failure of satellite bearings, reduction gear, 2nd turbine rotor blades, PCU with increased travel, cold chamber starting tests, anti-icing, failure of 6th row comressor blades, turbine failure, pollution of both engine oil systems as a result of single unit failure