Fire to be opened on Unseen / Unidentified Aircraft 13th August 1940

[Observer1940]

The rules for opening fire in 1939 appear to be that fire would not be opened unless the aircraft commits a hostile act.

However, I have been going through my photocopies from the PRO (TNA), Kew and discovered that the rule about not firing on unidentified aircraft was changed on the 13th August 1940, Dowding also signs the minute off by saying - Agree, see that everyone is told.

In another RAF Bomber Command file about incidents with our British defences, a September 1940 memo, indicates they have reverted back to the 1939 rules, stating that fire must not be opened unless the aircraft commits a hostile act, or is definitely identified as hostile.

During an RAF Court of Inquiry into the shooting down of a No. 10 OTU Whitley 5th August 1940 by fighters from RAF Silloth 17 Group Coastal Command, a Signal transcript sent to Coastal Command and the Group in late July 1940 was produced to the Court stating that aircraft must only be engaged if identified as Hostile or the aircraft commited a hostile act, the Signal also states - better for a hostile aircraft to escape than to shoot down one of our own aircraft.

By agreeing on the 13th August 1940 to open fire on unseen (unidentified) aircraft, the 1939 Rules of Engagement were being breached, without authority?

Mark