Hi Simon...Thank you..The 1100mm version I have was produced with turn and retract units which as far as I can tell from all the videos of gear retraction I have looked at are identical to mine, which fit perfectly, they just turn the wrong way jamming the doors. Unfortunatley they are one piece units and cannot be turned around and as you say it has been discontinued for a while, and even when in production spares were virtually non existant..I believe you are correct in saying that the sequence of the retract process is controlled within the retract..I think I am screwed..But thank you for taking the time to help me. All my other foam a/c are E-flite...different ball game and all my big gas powered a/c I built myself so know the fixes...It is a mystery......