The lock-on audio tone for the AIM-9 Sidewinder heat-seeking missiles is incorrect. The AIM-9, while seeking for a target, actually makes a growling tone that is heard by the pilot. When the missile locks onto a target the growl turns into a constant buzzing.
Before the race at the beginning of the movie, Chappy is working on Doug's plane. Doug asks "What are you doing making my mixture so rich?". The only things accessible through a Cessna's cowling hatch are an oil dipstick and possibly a fuel sump. The fuel/air mixture can be adjusted with a control on the instrument panel, easily accessible to the pilot in flight.
The names of U.S. air bases in Europe are mispronounced and misspelled. Torrejon Air Base, Spain, is pronounced "Tore-uh-hone", however, the maintenance supervisor mispronounces it as "Tree-John". Hellenikon Air Base, Greece was misspelled on Doug's aircraft display, and mispronounced by Chappie as "Helicon". It is actually pronounced "Hel-en-uh-con".
When standing outside Chappy's trailer, Doug mentions all the different weapons systems that he could have the F16's armed with. He says "all the 30 millimeter rounds the G-pod can carry". The F16 is armed with the M61 Vulcan cannon which fires 20mm rounds, not 30mm. The General Electric "G-Pod" was an externally-mounted cannon which was briefly tested on the F-16, but did not see widespread operational usage.
All throughout the movie there are many continuity errors with aircraft in flight: changing between one-seat and two-seat aircraft; the number of external fuel tanks they are carrying; the number of weapons remaining on them. This also clashes with the dialogue, with characters claiming no weapons remain while subsequent external shots show the opposite.
When Doug and Chappy takeoff for the first time to train together there are 2 F-16s on the runway (theirs plus one more on the left side of center line), but when they show their jet rotate during takeoff the 2nd jet is gone.
In some scenes, Doug is driving a red 1966 Mustang convertible, clearly identified by the dash configuration, and the pitchfork quarter panel trim. In other scenes, He is driving a 1965 Mustang which is identified by the honeycomb grille and wings on the corral in the center (not installed on any '66 model)
Insignia shown at Ramstein Air Base, Germany depicted the base as being part of the Tactical Air Command. Ramstein was never a part of Tactical Air Command, it comes under the command of United States Air Forces in Europe.
In the entire scene where Doug and Chappy are walking on the tarmac, the flight suit that Chappy is wearing displays incorrect patch(es). One in particular is a patch for the "131st Rescue Squadron - ALERT"; that squadron is located in California and have never operated F-16's.
Doug creates a wall of flame across a runway using the "Hades Bomb," a completely fictional weapon that does not exist in the U.S. Air Force inventory. He also fires an AGM-65 Maverick missile while on the ground, which is not possible in real life - the F-16's weapon system is inhibited by a pressure sensor in the nosegear.
The M-61A1 cannon does not require a radar lock to shoot at a target, and is not affected by any operating mode of the radar. The radar could be turned off, and the cannon would still operate normally. In reality, no weapon that the F-16s carried in the film required a radar lock to operate. The AIM-9 Sidewinder air to air missile tracks via the target's IR signature, not a radar lock.
During the graduation scene where Doug is remembering flying with his dad, after they land, Doug's father, Colonel Masters is approached by a the guy he was flying with, a Major. During this scene, when Col. Masters is questioned by the Major about the maneuvers he saw and the music he heard, Col. Masters responds in a subservient manner and is the first to salute. A Colonel outranks a Major. The Major should always be the first to salute and should be the one to act subservient to the Colonel.
All of the pilot's oxygen masks are not "tacked." Tacking a mask means the mask straps are sewn together so they don't come loose and fall out during flight. It is required by AFI 11-301, Aircrew Life Support Programs.
Towards the end of the film during the attack on the airbase, there is one shot in the film which displays a digital readout in the center of the cockpit which contains the word PRINT and a following function. PRINT is a command in the BASIC computer programming language and is used to display text in programs.
When Milo is using the computer to access intelligence data, the screen lists a "Su-19 Fencer." This is incorrect as the Fencer is actually the SU-24. This confusion exists because in early 1974 U.S. Chairman of the Joint Chiefs of Staff Admiral Thomas Moorer announced the new Soviet plane as a SU-19 Fencer (due to an incorrect NATO designation that was corrected afterwards); even today some references incorrectly mention the SU-19 Fencer. Still, USAF data in 1986 would have the correct NATO designation of SU-24 Fencer.
During and at the end of the race between Doug and Notcher, the Cessna 150/152's flaps are extended. Flaps increase drag and would be used to slow the aircraft. It is implied that Doug is flying at maximum speed to try and beat the motorcycle to the finish line. This couldn't be done with flaps extended. It is an obvious production necessity to make it appear that the race is close. Otherwise the Cessna would easily leave the motorcycle behind.
When Col. Masters is engaging the enemy in the beginning he comments that the enemy is flying MIG 23s. While his (simulated) radar image distinctly shows a MiG-23 Flogger with its wings swept back, the aircraft he is engaging are obviously delta-winged with canards.
Many of the external shots of the aircraft during flight clearly show that these are remote controlled scale models. This is evident by the jumpy flight characteristics. Full size aircraft do not behave in such erratic manners.
During the opening, an interior shot of Col. Masters' cockpit is shown, showing the altimeter, vertical speed indicator, some red LED numerals, and a hydraulic pressure gauge. The altimeter reads 10,700 feet on the dial, but the hands of the altimeter are pointing to 27,220 feet.
All aircraft used in the movie are not USAF F-16s, they are in fact Israeli AF aircraft. Their camouflage was not repainted, but their roundels were. In fact you can see patches of paint where US markings were painted over IAF markings, and where Stars Of David roundels were painted over. In addition, there are too many Stars and Bars US Military symbols on the -16s. There should only be four. One on the Top of the L wing, one on the bottom of the R wing, and two on the rear top of the fuselage between the wing and horizontal stabilizer. The F-16s in the movie carry six, one on both L and R top and bottoms of the wings.
The goof items below may give away important plot points.
Shortly before the final dogfight, a flight of six "MiGs" is shown on screen. One diverts to the airport so the Minister of Defense can fly it. Doug shoots one down and says "One down; one to go" when he should say four to go. He then shoots down another, and finally destroys the plane flown by the Defense Minister. This leaves three more enemy planes, but only two are shown pursuing Doug as he attempts to flee. The sixth and final "MiG" is unaccounted for.
Doug drops the Hades bomb to put a wall of flame between him and his father and the opposing forces. But if you watch the next scene the Hades bomb is still attached as he lands. It's gone again when the Masterses take off.
After the mission, General Edwards says that Doug and Chappy are accused of violating nearly every section of the National Security Act. Passed in 1947, the National Security Act simply reorganized the structure of the U.S. military. It didn't contain any provisions that could be violated and prosecuted in either military or civilian courts as specific crimes.