The "police helicopter" used in this episode, in which Wycliffe flies over the archaeological site and then lands near it, is G-BHXU - the same one that was used in almost every episode of the game show Treasure Hunt (1982), and the helicopter pilot is Keith Thompson who flew Anneka Rice and Annabel Croft in Treasure Hunt.
Louise Jameson who plays Tilly was also a regular on Bergerac and Dr Who.