The HX1 is a Sikorsky S-76.
Dunnkirk mentions the intended buyer of the stolen HX1 is Libya.
Although the location of the arms deal in the climactic scene is referred to as Red Rock Flats near Mineral Wells (on Airwolf's map as near Highway 30), it is a fictional location.
P.J. Soles plays a character in the military as she also did in the movie Stripes (1981). Also in the movie Stripes was Lance LeGault, who played a couple of characters Hawke had to deal with in previous episodes, and one more character in a future episode.
PJ Soles and Charles Cyphers previously starred in John Carpenter's Halloween (1978) as Lynda and Sheriff Brackett. Cyphers returned in the sequel Halloween II (1981) which also featured Jack Verbois as Ben Tramer. All three guest star in this episode.