Monument record 0941900000 - NE of junction of Broadway and A41

In 1940 a dummy airfield was set up at Grendon Underwood on the east side of the Broadway, at the junction with the A41. Designated as a 'Q' site for the airfield at Bicester, it was on the most common flightpath for enemy aircraft. Mock-ups of aircraft were positioned permanently in the field and lights resembling landing strips were illuminated during enemy incursions. Anti-aircraft guns were also stationed locally. The only sign of the airfield now [2000] is the remains of two shelters used by site personnel. [Photo, list of bombs exploded in the parish in 1940, and further details of decoy airfields](B2).
Grendon Underwood was a decoy airfield for RAF Bicester, operating as both a day-time decoy ('K' site) and a night-time decoy ('Q' site). The 'K' site was first mentioned in official documents on 13th March 1940 and closed on 27th June 1941, whilst the 'Q' site was first documented on 19th June 1940 and last mentioned on 12th August 1942. The 10 dummy aircraft used on the 'K' site at Grendon Underwood were Battles, produced by the former film props department of Gaumont British Studios (B3).
The Q site was a 'T-type' decoy layout (B4).
The layout of the decoy airfield is not clear. B3 records the NGR as centred on SP678 198.