Minutes of D.Eng.RD meeting held at Armstrong Siddeley Motors

34 present including Capt Luby (MoS); Mr Saxton, Mr Slatter Armstrong Siddeley Motors; Air Marshall Sir JN Bootham CS (A). Agenda: 710 (662) Sapphire contract position. 712 (664) test position: (a) 8000 lb thrust type test satisfactory. (b) 150-hour development test on Sa.106 satisfactory. (c) Attempt at 150-hour test on engine incorporating (1 25% reduced number of compressor blades in stages 8-12 inc. to improve performance. (2) new single row compressor outlet strightener vanes. (3) 1st row turbine stator blades in G.38 material. (4) Strengthened exhaust cone struts. (5) Redesigned fuel control to prevent sticking. (6) Production type Mk.9 acceleration control. The enine suffered a failure of an 8th stage compressor rotating shroud ring due to low stator blade tip clearance reulting from build error. (i) Reheat development: Armstrong Siddeley Motors had attained a thrust of 10,000 lbs with an overall specific of 1.72% which was a 25% increase over the standard engine. (j) Flight engines: 3 8000 lbs thrust unrestricted engines despatched for 1st GA.5 aircraft and one for F3/45 aircraft. Sapphire future programme: Civil clearance for Sa.3. 715 (667) Flying test beds: AST Lancastrian VM.733 (Sa.3 & Sa.6); Gloster Meteor WA.820; Canberra WD.933; Canberra 2nd aircraft. 719 (671) Prototype aircraft: Gloster F4/48 (twin); Gloster T118D Trainer (twin); Handley Pge B35/46 (4 engines); Hawker F3/48; English electric F23/49 (twin). 724 (676) Adder: Running time now 1630 hours. 725 (677) Test position: (a) Handling has now improved; (b) Australian flight engines have now been despatched. 726 (679) (a) 13 engines delivered to Australia. (b) Adder in tail of Mamba Lancaster. (c) Vickers C9 resreach aircraft. 727 (680) Viper: Running times now 236 hours. (e) Vipers V.5 and V.6 accepted. V.5 allocated to Mamba Lancaster FTB. 729 (682) Future programme: (a) Bristol application for Viper. it was agreed that 2 Viper engines would be taken from existing development engines to expediate delivery for the Bristol application owing to extended delivery of material for the production engines. Armstrong Siddeley Motors will write to MoS stating the differneces required for the Bristol Viper and Mr Golovine stated that he would clear the contract position. 730 (683) Double Mamba: Running times now tatal 5477 hours. 731 (684) Test position: (a) 150-hour Type test; (b) 150-hour development test D.201. (c) Parkerised gears; (d) Hot spots on combustion chamber outer casing; (e) Dowty fuel pumps; (f) Turbo starting. 734 (688) Fairey 2nd aircraft VR.557; 735 (689) Fairey 3rd aircraft WE.488 (3-seater); 736 (690) Blackburn GR.17/45 WB.797. 737 (691) Mamba: Total running times to date 4264. 738 (692) Test position: 150-hour modification approval test; (b) Apollo engines: 5 delivered. Armstrong Siddeley Motors stated that they were still awaiting MoS policy regarding the 2nd batch of 6 engines. 739 (693) Aircraft: Lancaster SW.342; Apollo GA IYN; Dakota Kj.839. 742 (696). 742 (696) General development: Mamba engines for Short SB.6 aircraft. 743 (679) Python: Total running times 1853 hours. 744 (698) Test position: (a) Twin disc turbine; (b) Inertia PC units; (c) ECU having withdrawable hydraulic stop; (d) Strengthened front propeller gears; (e) Clearance of roller satellite bearings on oil to Spec. DERD.2472; (f) 3-stage turbine; (g) Turbo starting; (h) Alternative fuels; (i) Twisting of reduction gear torsion bars 745 (700) Aircraft: Wyvern Vp.109; Wyvern VW.868 provisioned for Armstrong Siddeley Motors; Wyvern VW.882. Rocket: 748 (705) Snarler in Hawker VP.401. The aircraft has now left Bitteswell for disposal; 749 (706) Screamer rocket motor: Avro are primarily interested in a single chamber rocket motor of 8000 lbs thrust. 750 (707) Armstrong Siddeley Motors require aircraft for Screamer tests: Armstrong Siddeley Motors prefer a Canberra, but if not available will improvise with a Meteor 8. Report on air turbo rocket; New test house and plant. Armstrong Siddeley Motors claim they could not test a rocket motor of more than 4000 lbs thrust if the existing test house was not supported by the safety Committee. Appendix 1: Sapphire 95 AS.Sa.3 to 412 AS.Sa.4. Appendix 2 Python: 101 ASP.1 to 134 ASP.3. Appendix 3 Mamba: 101 AS.Ma.1 to 174 AS.Ma.3. Appndix 4 Double Mamba: 201 AS.Ma.D.1 to 208 AS.Ma.d.1. Appendix 4 Adder; Viper 1 ASV.1 to 10 ASV.1