A story about false signals from Monica radar.




Temporal Coverage

Spatial Coverage



One typewritten sheet


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[underlined] MONICA. [/underlined]

On the night of the 9th August 1943 Lancs from 9 squadron
in 5 Group set out for a raid on Mannheim. The gunners were feeling
more confident than usual because they had Monica with keep
them company. Monica was a new electronic device for detecting
approaching night-fighters. An aerial was fixed just below the rear
turret and approaching aircraft were detected by an audible bleep
in ones headset. The faster the bleep the nearer the aircraft.
We arrived at the target and were granted the usual
unwelcome reception. Having dropped our load and with the starboard
outer out of action we headed for home. No sooner done than Monica
came into her own. As soon as the bleeps started the crews visual
search intensified and I gave the order to corkscrew. As we went
into the initial diving turn Monica stopped. There was still no
visual siting. This pattern of action continued till we reached
the French coast. What with the constant evasive action and the
loss of one engine we crossed the coast in daylight!
On landing we were met by an enraged CO who demanded
to know why we were late! He had just stopped the telegrams from
being despatched. After heated explanations, during which he insisted
we had got lost, tank dippings and close scrutiny of logs it was
discovered that Monica had been u/s!
Our action having been justified we were posted
to 3 Group a month later - but that's another story. I have never
trusted a Monica since.
302 P.A.S. Twinn


PAS Twinn, “Monica,” IBCC Digital Archive, accessed November 28, 2023,

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