Mosquito Squadron

The whole pre-credits sequence in its entirety was taken from the studio's previous picture, Operation Crossbow (1965). This movie would also utilize footage from the studio's earlier 633 Squadron (1964), most noticably the shot of Munroe rolling on the ground to extinguish the flames on the back of his flying jacket, after rerturning from the recon mission.

The Bouncing Bomb used in the film was a real weapon. Known as Highball (a smaller version of the Dambusting Upkeep bomb), it was originally designed by Dr. Barnes Wallis to be utilized against battleships, such as the Tirpitz. The Highball bomb weighed 1,280lb (580kg), carried 600lb (272kg) of explosive, and was small enough to be carried in tandem by a Mosquito fighter-bomber. Prior to release the bomb was imparted with a backward spin of 700-900 revolutions per minute, and dropped at high speed (360 mph (580km/h)) and low altitude (60 ft (18.2m)).

The exquisite Chateau de Charlon seen in the movie was portrayed by Minley Manor, a Grade 2 listed country manor house, near Yateley and Farnborough in Hampshire, England. Minley Manor was the Officers' Mess of No 3 Royal School of Military Engineering at Gibraltar Barracks for over 20 years.

With a maximum airspeed of 415 mph (668 km/h) the DH Mosquito was one of the fastest propeller driven aircraft of WWII. A ceiling of 28,000 ft (8,500 m) and a range of 1,300 mi (2,100 km) along with its speed permitted it to fill roles in multiple categories; e.g. Fighter, bomber, close ground support, reconnaissance. The de Havilland Mosquito is a remarkable aircraft and the film a wonderful tribute to it.

The British aircraft featured in this film, the DH98 De Havilland Mosquito, was unique among WW!! operational aircraft in that, due to a wartime shortage of strategic metals, its wings and fuselage were skinned with a plywood laminate material instead of the aluminum alloy usually used on aircraft of this era. For this reason the plane was sometimes referred to as the Wooden Wonder. Howard Hughes' famous "Spruce Goose" used a similar material.