到1942年年中,英国超级海洋喷火面临数项挑战。1941年底,强大的Focke-Wulf Fw 190的首次亮相给英国皇家空军战斗机中队驾驶最新的喷火Mk Vb.劳斯莱斯的工程师们带来了麻烦, 劳斯莱斯的工程师们已经在研究一种新版本的梅林,它结合了两级增压器:改进的梅林和喷火Mk VC机身在"权宜之计"设计的组合,使英国皇家空军在同等条件下打击Fw 190。在第二批开发中,Supermarine 正在开发改进、加固的喷火机身,该机身包含多个新功能,专为 Merlin 60 和 70 系列发动机而设计。这种新的机身后来成为劳斯莱斯格里芬动力喷火的基础。
Mk IX (类型 361):
BS456 UZ-Z of 306(Polish) Toruński Squadron, RAF Northolt, November 1942. A Spitfire IX converted from a Mk VC airframe. A teardrop shaped blister for a Coffman cartridge starter can be seen just behind the propeller. This aircraft carries a 30-gallon “slipper” drop tank under the fuselage.
In the early months of 1942, with the clear superiority of the Focke Wulf Fw 190 over the Spitfire VB, there was much pressure to get Spitfires into production using the new two-stage supercharged Merlin 61 engine. In September 1941 the Spitfire Mk III prototype N3297 had been converted by Rolls-Royce at their Hucknall plant to take a Merlin 60, which had been specifically designed for use in the Wellington Mk VI high altitude bomber.
源: 维基百科上的喷火