Originally Posted by
frontlefthamster
I pointed out, in the lost thread, that the leisure aviation community was unwilling to accept Mode S. I said that, in my view, those who voted against it gave up their right to bemoan collisions. If you can't be bothered to put up with the expense and weight of fitting a transponder, you have no right to worry about collision, because you could have done something to avoid it and you haven't.
The 'leisure aviation' community didn't object to Mode-S as a whole - the arguments where that Mode S vs Mode C was unnecessary and that it was not technically possible to fit transponders to many aircraft and in light of this technical detail a mandate to do so was silly. (there was a smaller 'civil liberty group' who have objected to transponders on general principle and I would agree with your comment as it applies to this group)
In addition - and possibly relevant in this case, was the argument that the lack of TIS and/or 'lars' Radar Service resulted in very little benefit to those fitting the technology. It will be a very sorry comment on the Safety Regulation approach of the UK if it transpires both aircraft were transponding.
The 402 surely had Mode-S and Glass (so in the US would have TIS). In addition, the decision by the regulator to allow the sale of radar data to support NATS' profits rather than cover marginal cost (and therefore being 'expensive') will have been a part in Coventry operating their own primary only radar rather than a primary/secondary feed from NATS. My untrained eye finds it much easier to see conflicts on the NATS screens than on Coventry's.