“WAAF”

Data:

• During World War II, British Women's Auxiliary Air Force (WAAF) personnel used large cicular slide rules to calculate bomber routes, undertake meteorological forecasting, and plot aircraft positions. (Source: Computer History Museum)
  A similar device was used by ATS (Britisch Army Auxiliary Territorial Service) for calculating A.A. (Anti-Aircraft) Gunfire Accuracy using a kine-theodolite, a film evaluator and a slide rule. photo 1 and photo 2. Andries de Man
  “The ATS girls are good draughtswomen are useful for making slide rules and other A.A. equipment for experiments” (annotation on photo of Pte. Kathleen Lavery designing a special plotter). Jose Fernández
  You can see the device in action in the video “Girls Work Kine-Theodolite” (at 61 seconds)
  More on the kine-theodolite, auxillary instruments and calculations: cdvandt.org Andries de Man
  

Questions:

1. Who manufactured this slide rule?
   There is currently (October 2026) one for sale in Norway!
   From the seller's description:
   In typical military fashion it is called a “Rule, Slide, Kine-Theod[oli]te, Mk. 1” and is also marked “Reliance, Twickenham, 1940 Regd. No. 30” Andries de Man
   Graces Guide mentions Reliance Nameplates Ltd, Richmond Bridge works, Cambridge Road, Twickenham as a manufacturer of nameplates and dials.
   Is this the manufacturer?
   Straight Reliance slide rules are known, e.g. from the collections of David Rance, Tina Cordon and John Mosand, with just the word “Reliance” and a helmeted head (Minerva?) logo
   David's and Tina's slide rules also show the UK government broad arrow mark. Andries de Man
   In the 1920s Reliance Nameplates Ltd. Twickenham was producing celluloid acetate tokens. The company continued to use the original type of press until 1963 when the production of celluloid acetate tokens was discontinued. worldofcoins
   The 1974 edition of “Kelly's Post Office London Directory”, pages 1331, 1731, 2025 mentions Reliance Nameplates Ltd., Richmond Bridge works, Twickenham, Middx, in sections “Dial manufacturers”, “Nameplate engravers — ivorine”, “Nameplate engravers — metal.”
   Note the advertisement does not show the helmeted head logo. Andries de Man
   
2. What scales are on it?
   Inner ring: Base Angle, Apex Angle, Angle of Sight.
   Outer ring: Height Feet, Base Yards (partial scale).
   Andries de Man
3. How does the cursor work?
   Summary: Slide Rule Disc for Kinetheodolite Jose Fernández