Martial arts expert and fight choreographer Michael M. Vendrell worked with Arnold Schwarzenegger on the film and by the end of production, Vendrell estimated that Schwarzenegger had become a second degree black belt.
Vernon Wells wasn't the original actor cast to play Bennett. He did audition for the role, but another actor got it. On the first day of filming however, director Mark L. Lester fired the other actor and hired Wells. This is the reason that Bennett's clothes seem so tight, because Wells was bigger than the original actor, and the production didn't have time to make a new costume. Over the years, a rumor has developed that Wells originally auditioned for the part of Matrix, but this is false.
Arius (Dan Hedaya) is said to be a deposed dictator from the country of Val Verde. Val Verde was a fictionalized South/Central American country used by Hollywood from the 1980s to early 1990s to depict a Spanish speaking country similar to Cuba or Nicaragua without encountering diplomatic problems. It is also referenced in the films Predator (1987), Die Hard 2 (1990), and the made for TV movie Supercarrier: Deadly Enemies (Pilot) (1988).
The surplus store where Matrix picks up all the war toys during his night "shopping" was "Surplus City" in Sun Valley, California. A movie addition to the building (on the driveway) allowed for the secret room, where the machine guns and the other fun stuff was hidden. In the 1960's, this company had the largest collection of military surplus 'jeeps' and 'mighty mites' for sale in the US.
John McTiernan was offered the chance to direct this film, and turned it down. Later, while editing Nomads (1986), his feature debut, he was offered the chance to direct Arnold Schwarzenegger's second film for 20th Century Fox, Predator (1987), which he accepted.
Screenwriter Jeph Loeb originally wrote the script with the intention of having Gene Simmons play Matrix, but Simmons passed on it early in the developmental stage. Loeb then rewrote the script with Nick Nolte in mind as an out-of-condition former Commando. The storyline was to concern a special forces agent working in the Middle East who becomes sick of the continuous death and destruction. He leaves Israel, returns to the United States and retires, but he is then forced out of retirement after the kidnapping of his daughter.
Matrix goes into battle with an Valmet M78 light machine gun, an Uzi submachine gun, a Remington Model 870 combat shotgun and a Desert Eagle automatic pistol. He also commandeers an M60E3 belt-fed machine gun and an M16A1 assault rifle.
The shot of Matrix standing on the landing gear of the plane as it races down the runway was shot by constructing the wheel section of a plane and attaching it by hydraulics to the side of a camera truck.
The introduction to Matrix as he comes out of the forest, with close ups on his boots, chest, biceps etc was shot and edited in a similar fashion as Leni Riefenstahl's Nazi propaganda movies. According to director Mark L. Lester this was done to represent the notion of the invincible man of the earth emerging from the forest.
The combat vest that Matrix wears is a real combat vest used by the Air Force's Parachute Unit. The vest was designed by Group 5, a combat clothing manufacturer from Texas who do not sell to the public.
Western Airlines was an actual airline. It was headquartered at Los Angeles International Airport and operated a second hub at Salt Lake City International Airport. In 1987, Delta Airlines acquired Western, and to this date still maintains a strong presence at LAX and SLC. After the acquisition, however, Delta sold off Western's fleet of McDonnell Douglas DC-10's (like the one seen in the film) because it already had a large fleet of Lockheed L-10ll TriStars.
The trivia items below may give away important plot points.
The mansion used in the final shootout between Matrix and Arius (the former Harold Lloyd estate in Beverly Hills) is the same mansion see in the final shootout between Axel Foley and Victor Maitland in Beverly Hills Cop (1984).
During the scene in the shed, after Matrix cuts the soldier's arm off, he was originally supposed to hit the victim with it and say "Need a hand?" This scene was never shot however, as it was considered too macabre. Despite this, the 2007 director's cut restored a few extra seconds of footage of Matrix tossing the cut limb nonchalantly at the wounded soldier, as most likely a "lighter" alternative to blatantly hitting him with it.
Just after Matrix plants the claymore mines, he is seen shooting a knife into a guard's stomach. The knife he used is a Russian Ballistic knife that uses a spring to launch the knife blade out of the handle.
Matrix's raid on the complex at the end of the film was shot on a beach in San Simeon, California, near William Randolph Hearst Castle. Originally, the scene was to be shot at Palace Verdes in California, but two days before shooting, the coast guard pulled the permits.