Factual error: The scene in which the Beechcraft Baron hits the Boeing 747 in flight plumbs new depths in cinematic absurdity. Assuming both aircraft are at their normal cruising speeds - they appear to be - and the Beechcraft has half a fuel load left, it will hit with the same energy as 7,700 kgs of TNT. The Beechcraft Baron weighed 3,200 kg and the two aircraft would have a closing speed of something like 700 kmh. Even a glancing blow would tear the entire front half of the 747 to bits - there would be virtually nothing of the fuselage left intact all the way back to the wings, and the film shows the two aircraft on course for a head on collision.
Factual error: The film's car chase takes place in Thailand, where vehicles are right-hand drive (RHD) and travel on the left side of the road (as in England and Australia). Yet the American Motors (AMC) cars in the chase - the red Hornet X, gold Matador coupe, and several Matador sedan police cars, all 1974 models - are all left-hand drive cars. Scaramanga's car can be excused as something he specifically imported for himself, but the Hornet is 'borrowed' from a fictitious AMC dealership (none existed outside the USA) and the small amount of AMC vehicles sold outside the USA were shipped disassembled to various companies that reassembled them and sold them under their own company names (AMI in Australia, Karmann in Germany, etc). Companies such as these, in RHD nations, had to modify the cars to RHD themselves in order to be allowed to sell them 'locally'. So the Hornet would have been at a non-AMC dealership and would have been RHD, as would the fleet of police cars. Naturally, this 'error' was created by AMC's promotional deal with the filmmakers to use AMC cars in order to improve US sales to the US filmgoers.
Factual error: The device used near the end of the movie for ferrying people to another building is repeatedly referred to as a "breeches buoy." It is actually a highline transfer chair. A breeches buoy was an earlier, more primitive device that was basically an oversized life preserver with a pair of large canvas trousers (breeches) sewn to it.
Factual error: When the cops are staking out Charles Bronson's apartment, one orders the other to go to a pay phone and call him. He runs towards Riverside Drive, going west, and finds a broken phone. Then he runs to a subway station and makes the call. He returns from the same direction. Well, there are no subway stations on Riverside. The nearest is two long city blocks away, going east. Even if he ran that far, he would not have returned from the same direction - he would have come from the east.
Suggested correction: What matters is how much of the small plane's kinetic energy was deposited in the 747's structure. A glancing blow would deliver less energy than a head-on collision, because it lessens the total time interval of the impact. Another important thing is if the small plane shattered or stayed largely in one piece during the collision. If it promptly shredded on impact, then each little fragment carried away its portion of the total energy. Smaller pieces of something as light as that plane would immediately get caught in the powerful airflow and be diverted around the 747.
Absolute rubbish. Airliners do not survive mid air collisions.