Here's a photo of part of the collection. Out of curiosity, I tried test gliding the gold-coloured 'Space Plane' - but this confirmed my feeling that it had never flown, as a well trimmed brick would have fared rather better. The suggestion that these 'motors' might be smoke generators is intriguing, and might well be correct.
Roger adds:
Hi David, don't give up so easily! Anything will fly with enough power! Put in a new L-3, give it a catapult launch and watch it go! You could be the first modeller to break the Sound Barrier!