1419 Flight hut, RAF Stradishall
S/Ldr Knowles writes to an erstwhile colleague at the Air Ministry. The name of this colleague has been withheld under Section 3(4) of the Public Records Act, 1958:
28th April, 1941
With reference to “SKYLARK”, I have looked up the longitude and lattitude (sic), and it is 59 degrees 50 minutes North, and 08 degrees 36 minutes East. I suggest you go down to the Map Section in Air Ministry, and look at a decent map of Norway (1:500,000 Stavanger), and you will find VIKEN if you put three pairs of spectacles on.
(Signed) E.V. Knowles, S/Ldr.
Prior to the file’s release a zealous file-weeder has mistaken the Air Intelligence section ‘A.I.(10)’ (the initialism for SOE at the Air Ministry) for A.I.1(c). The latter section of Air Intelligence contains several embedded SIS officers, including W/Cdr Frederick Winterbotham and W/Cdr Vincent Sofiano (mentioned several times by Hugh Verity). To be fair, the ‘0’ in the typed ‘A.I.(10)’ does resemble ‘A.I.(1C)’, but close examination reveals the error. Knowles would have known the SIS section’s proper designation as ‘A.I.1(c)’.
In my view the intended recipient is Knowles’s friend Wally Farley, promoted Squadron Leader on 1 April and currently clumping around the Air Ministry corridors with his leg in plaster. During this period Farley writes as ‘A.I.10’ or ‘A.I.2’ depending on context, but never as A.I.1(c).
The position of ‘VIKEN’ is about three miles south of the hydro-electric station at Rjukan, producer of ‘heavy water’ — deuterium oxide (D2O or 2H2O) — and later target of operations against the German attempts to develop an atomic weapon.
TNA AIR 20/8334, encl. 6A