Interesting reference to main gear collapse. At the time of the UN Congo intervention in July 196o I was working for Shell in Accra, Ghana, where the troop airlift was centred, helping out on refuelling from my normal job as a sales rep.
The RAF sent a Comet 2 and a Hastings. When the Hastings arrived and I went on board to take their fuel requirements I enquired why their only cargo was a complete spare main landing gear (with wheel). I was told 'they tend to collapse so we brought a spare'. Unfortunately they had failed to bring a toolkit so to open the engine oil dip hatches they had to borrow a screwdriver from my car toolkit.