From 28:00 on the narrator talked about gunsights.
1. - He called the N9 the K9 while the film showed a P47 with a NAVY Mk8 which at least was correct. In the ETO almost all AAF fighters were refitted with the RAF MKII until the P51D. P38 kept the N3 and subsequent L3 due to space constraints. Sperry made K9 which was an upper turret gunsight in B24. The N9 was initially fitted to P51-D from the factory, never B\C, and rapidly replaced with the K14 in late 44.
2. - The description of the K14 gyroscope not being able to work during high G maneuvering was correct. During high G maneuvering the 70Mil ring and dot fixed reticle on the early K14 was the same diameter as the reticle in the N3 gunsights that the AAF had taken out and refitted with British MKII for it's 100Mil ring. A 70Mil ring was found to be useless for deflection shooting at the higher speeds fighters maneuvered at.
One complaint by pilots of the K14, was the white reticle projection was lost against a background of white clouds. N3, L3, Mk8, MKII, and N9 had a yellow or orange diffuser.