Tracer wrote on IMDB:
_Airplane!_ was so closely based on this movie that the list of DIFFERENCES
between this movie and _Airplane!_ is shorter than the list of
similarities.
Some of the differences between _Zero Hour!_ and _Airplane!_
are:
*) The only two characters with the same names are Ted Striker and
Joey.
*) In ZH, Ted Striker's ill-fated air raid during the War was dramatized in
its entirety at the beginning of the movie, not reconstructed piecemeal in
flashbacks over the course of the film -- although Ted did have a couple of
flashbacks in ZH at crucial moments.
*) The flight in ZH is a DC-4 carrying 38 passengers from Calgary to
Vancouver, BC. The airspeed indicator for the DC-4 only went up to 250
miles per hour. [ show more ]
*) In ZH, Ellen (the character that became Elaine in _Airplane!_) was Ted
Striker's wife, and Joey was his son. Joey was among the unlucky passengers
who ate fish (halibut) instead of meat (lamb chops), and he gets so sick
that he symbolically breaks the toy airplane the pilot had given
him.
*) The pilot in ZH succumbs to food poisoning slowly, and manages to keep
the plane under control for an hour or so, thanks to a morphine injection
administered by the Doctor, until he finally collapses. The automatic pilot
(not inflatable, of course) was already engaged by then.
*) Nothing like the Knute-Rockne-based inspirational speech that the Doctor
gave to Ted Striker in _Airplane!_ is anywhere to be found in
ZH.
*) In ZH, the unmarried stewardess had a boyfriend on board who tried to
cheer up Joey with a glove-puppet.
*) A tense moment happens in ZH where the plane's radio accidentally gets
knocked off the proper frequency and Ted Striker is on his own, cut off from
communication with the ground, until Ted and Mrs. Striker can find the
frequency again. This sequence does not appear in _Airplane!_.
*) In ZH, when the air traffic controllers went looking for Ted Striker's
old commanding Captain, they first had to call his babysitter at home (who
had Elvis Presley turned up way too loud on the TV to hear them), and then
had to call a nightclub where said Captain and his wife were dancing to an
equally-loud jazz band. [ show less ]
Written on IMDB a long time ago.