November. The engine ran for the first time on 22 April 1943, only 166 days after the contract was signed. The engine was soon producing 2,000 lbf. As soon as the Air Ministry was satisfied the company was able to make engines, they granted Armstrong Siddeley permission to make a Heppner-derived version. However, the company gave up on this as well, and decided to instead use the ASX as the basis for a turboprop, which became the ASP. Thus the first example of the ASX would ultimately be the last as well. Testing continued on the ASX through the rest of the war, and by 20 April 1945 it had run for a total of 22 hours. Although A-S and Metrovick were not able to collaborate during the war, in the late 1940s the Ministry of Supply forced Metrovick to spin out their gas turbine division and handed it complete to Armstrong Siddeley in order to reduce the number of firms in the aviation business.So Armstrong Siddeley ultimately ended up with the F.2, and more importantly, the F.9 which would become the Armstrong Siddeley Sapphire. Design and development The ASX was unique in layout. The inlet to the 14-stage compressor was placed near the middle of the engine, the air flowing forward as it was compressed. From there it fed into 11 flame cans arranged around the outside of the compressor, flowing back past the inlet, and finally through the turbine. This layout allowed the compressor and combustion areas to be "folded" together to make the engine shorter, although the overall reduction in the case of the ASX appears to be fairly limited as the engine was almost long. Additionally, this layout makes it more difficult to service the compressor, although, at least in modern designs, it is the "hot section" that generally requires most servicing. The ASX was flight tested fitted to the bomb bay of a modified Avro Lancaster, ND784, the first flight taking place on 28 September 1945. At full power the engine ran at 8,000 rpm and developed of thrust at sea level. For cruise the engine ran at 7,500 rpm and developed . It weighed . The ASP conversion used a second turbine stage to drive the propeller through a gearbox, producing 3,600 shp, as well as of leftover jet thrust. Applications Avro Lancaster (Test only) Specifications (ASX) See also References Citations Bibliography Gunston, Bill.