Rolls-Royce RB Designations

[Hood]

@Apophenia
I have some further Adour entries for you!

RT.172-30
1974 project, upgrade option for Jaguar.

RT.172-58C
1978 project, a -58 with improved HP compressor blades; 5,260lbf dry, 8,470lbf reheated. Offered for 'Big Wing' Jaguar.

RT.172-63
1978 project, had all the features of the -69 but with a new afterburner developed from RB.199 technology; 5,540lbf dry, 10,100lbf reheated. Offered for 'Big Wing' Jaguar.

RT.172-69
1978 project, very similar to the -58C but with a 3-stage LP compressor and new turbine blades made by using a directionally solidified cast process. Digital fuel control system. 5,390lbf dry, 9,200lbf reheated. Offered for 'Big Wing' Jaguar.


I do have a mystery engine though.
An engine labelled "Rolls Royce 802"
It looks a bit like an RB.231 but equally could be an Adour with a fat reheat section. I don't know of any Adour Mk.802 however, and 802 would seem to indicate an export engine?

 

[zen]

Mild clarification required.
How is the RT.172-63 a development of RT.172-69?
Which is a development of
RT.172-58C?
Surely -69 comes after -63?

 

[Hood]

RT.172-58C was an improved -58 but was only a modest improvement, which is probably why it went no further.

The -60 series look more like a family of options and were another step along the evolutionary path with their new turbine blades and LP compressor section.
I think it would be fair to say that -63 was (at that time) considered the 'ultimate' Adour development with the -69 not having the RB.199-tech afterburner, probably as a lower-cost/risk option (and more compact too).
RT.172-66 for the Hawk would have been an unreheated version.

I suspect that the -69 was overtaken by the RB.231 which offered more power and more application of RB.199 know-how.