You are assuming that the glidepath is the only reference for an aircraft on a CAT III approach. But CAT III (and II) also require a radar altimeter, which would foil a Die Hard II scheme.
In addition, the aircraft would not be at the proper height for its location along the approach.
But it was a fun movie to watch, even if extremely unrealistic.
In North America, there is ONE refinery still producing it. And they pretty much only run a batch once a year - an entire day's production is sufficient for an entire year. Something like all the avgas used in a year is equal to all the regular gas used by cars in a day.
Don't suppose you have a reference for that assertion do you? There are several refineries in USA that make avgas, and production is much larger than a day.
In 2009 there were 10 refineries making avgas, this article indicates there "seven or eight" in 2011.
Check out this table , courtesy of the Energy Information Administration, for a summary of regions where avgas is produced.
The most exciting phrase to hear in science, the one that heralds new discoveries, is not "Eureka!" (I found it!) but "That's funny ..." -- Isaac Asimov