The Reactionaries were former members and associates of Whittle’s company Power Jets Limited who, during the years 1937 to 1945, were involved in developing Whittle’s novel concept of forward propulsion of aircraft by reaction from the backward momentum of a high velocity stream of hot gas. This was regarded as a vivid and practical illustration of Isaac Newton’s Third Law, that “Action and Reaction are equal and opposite”.

The concept of The Reactionaries was initiated in April 1946 at the Hind Hotel, Lutterworth by a group of engineers and others, in order to maintain contact with Sir Frank Whittle and each other wherever their careers might lead them. Some had been amongst the very first to work on developing the jet engine when he recruited promising graduate engineers from Cambridge and, not surprisingly, many of them went on to have distinguished careers.

An elected Honorary Secretary undertook to compile and disseminate an Annual Newsletter and to arrange an annual re-union – preferably as close as possible to 12th April or 15th May, in commemoration of the first run of Whittle’s experimental engine and the first flight of his W1 engine in the E28/39 aircraft in 1937 and 1941 respectively.

After uninterrupted newsletters and reunions for 60 years, a final reunion was held at Cranwell in 2001.

For some years after this the Sir Frank Whittle Commemorative Trust arranged a commemorative lunch for surviving Reactionaries and employees of Power Jets as close to 15th May as possible each year.