Viper Mk204 - Myth or Fable?
I know you guys are good, but this is one of those "always wanted to ask" questions that is a bit of a stretch.
The Armstrong Siddeley Viper engine was a nifty piece of kit, starting out as an ultra short life expendable target drone engine and eventually becoming a surprisingly reliable turbojet on many aircraft perhaps most notably the various versions of the JP.
The Mk202 version was installed in the T4 and T5, but there was a suggestion that the Mk204 was specifically designed with enhanced safety and durability features and installed exclusively in JPs that were used by HRH during his flying training.
Like I said, bit of a stretch but I figured that if anyone knew he would be on Pprune.