Along with some Footage of Phantoms, there is also footage of F-15's used in lieu of actual Mig-25 flight footage.
In the opening sequence, some external views of the defecting Mig-25 are actually of an F-4 Phantom. The Phantom has bent wings, while the Mig-25 wings are straight.
The buildings depicted as C.I.A. headquarters in Langley, VA look nothing like the actual complex. The film shows a group of very tall, individual metal-and-glass skyscrapers, where in fact C.I.A. headquarters are a squat group of interconnected, 5-storey buildings made of stone.