This is the Royal Aircraft Establishment, a state body that tested and approved aircraft and engines produced mainly in the UK.

-The RAF company (see) was dissolved and distributed in the times of WWI, this factory, also state-owned, became RAE. Do not confuse RAF from Royal Aircraft Factory with RAF or Royal Air Force.

-Its first technical director was the well-known AA Griffith (see) and in the 1920's he was already studying how to drive a propeller using gas turbines.

“AA Griffith”

“Griffith's 1929 project”

-Alan Arnold Griffith presented a turbine model around 1929. He devoted himself with his team to the study of axial compressors within the RAE, the first one being the A or “Annie”.

- Supporting itself with companies in the same branch like the English Parsons and Metropolitan-Vickers, and the Swiss Brown-Boveri. Annie is sometimes known as Anne.

“Annie compressor”

-The next project was B or Betty.

"Betty compressor and turbine rotor"

-It was followed by Doris, (project D) planned for 2,000 SHP. These were study machines that were gradually leading towards turbines for aeronautical applications.

"Doris Turbine"

-Projects like Freda and Sarah followed. The latter would give rise to the Armstrong Siddeley ASX (see). The Ruth compressor was manufactured at Fraser and Chalmers.

“F.1”

-Then came the involvement of Metropolitan-Vickers in the F.1 and F.2 engines. The latter took the Freda compressor as its basis. Between these two engines the F.1A was projected

“F.2”

-Griffith went to Rolls-Royce where he was able to carry out his first patent under the name of CR.1, see the Griffith chapter”.

From Appendix 9: When the Royal Aircraft Establishment was led by AA Griffith, before and during WWII, compressors and turbines were tested to support the development of jet engines.

-Shortly before, in 1937, Whittle started up its first engine of this type.

-Griffith gave each type of compressor its own name, focusing on axial ones and demonstrating their viability.

The first one was the "Annie" (see main text). Now my collaborator friend of this work sends me some photographs from the Manchester Museum, where a good part of this material can be found.

-I discover that there is the “Betty” compressor that is mentioned in this publication.

“Betty compressor” (Evzen V.)

-Actually, Betty's project included a second part that is shown in outline in the main text of this chapter.

"Clearly it is the part on the right"

-The complete project includes a group of turbines.

-The author does not know how to discern the situation of the combustion chambers, if it uses them.

-Neither the “Betty” compressor outputs are axial as we see now:

"Compressor outputs"

-What appears to be a continuation of the compressor at the bottom, is a Metropolitan Vickers Beryl engine, exposed and shown in the following illustration. This is project B.10.

"This is the Beryl that can be seen at the previous bottom"

-The Motropolitan Vickers (Metrovick) received the benefit of the RAE investigations. The result was a series of engines starting with the promising “Beryl”.

-Nor has it been possible to find out the group in the same photo, on the background at the left.

-Possibly another RAE try-out. Other compressors tested were the “Doris” (Project D), "Freda", "Ruth" and "Sarah."

-In the illustration below we see the assembly on the test support, very similar to those used in the RAE as we can see below.

"Unknown compressor" (Evzen V.)

"Betty B.10 bench tests"

-The Betty tests were carried out at the Trafford Park establishments around 1940 and the wind tunnel tests at the GEC Alsthom.