condor17 Thanks for this. I have just found the copy of the Squadron 60 movement report compiled at Wildenrath for October 1989. it includes "Operations" chapter 4. "a flight to Prague,Czechoslovakia, in order to acquire some pure Semtex explosive on which MOD were to perform tests." So its appears that the flight was to PRG rather than PED, but I guess the same entry to Czechoslovakia would have been the Cheb air gate.
Lance Shippey