Rustle, thanks for the link, which I have now saved. I now realise that my memory is primarily of collisions fatal to the glider pilot(s), which I believe power/glider collisions usually are. The one you pointed out was fatal for the power pilot and for some reason had not lodged in my RAM.
It was another case of power-flying-into-the-back-of-the- glider, both flying straight, in VMC.
None of my comments should be taken as dismissing dangers, nor of suggesting that power pilots are more likely to fly into the back of things than glider pilots. We all suffer from the fallibility of the eye, attention spans, etc.. I have written before, and still firmly believe, that only technology is going to make much difference, i.e. the poorman's TCAS - at least a proximity alert, preferably one indicating distance and direction of a threat within roughly the same height band. And it needs everyone to have the sender and the receiver to be fully effective, though the chances of avoiding collision will be improved with increasing levels of take-up. I am far from convinced that transponders are the entire answer, but if most people had them at least the heavy metal could avoid gliders and other GA (much of the non-glider GA also lacks any or all of radios, transponders, and paints on primary radar).
None of these will help the 40th glider avoid the other 39 in a thermal - only the eyeball, and airmanship using existing guidance for good thermalling practice can do that, I believe. Just as something similar will be the only way power in close formation, air-air photography etc., will avoid collisions in that sphere.
Meanwhile, the greatest danger to me of a collision is with another glider, in VMC, based on accident figures, incidents I and others have experienced, and my own analysis and judgement of the various scenarios and the relative lengths of time I am exposed to them.
Chris N.
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