You don't need hi-tech you need lots of eyes looking out of lots of windows.
Hi tech sure does help. Our Aero Club is part of the Norwegian CAP (RMK: Different system), and I've done SAR training as an observer in a Cessna.
You don't understand how much you miss before you try it.
Ex: We did a exercise where 2 dummys in blue coveralls was placed sitting in a alpine area of 3 x 3 nm. We (pilot and observer) missed both.
Even flying at 500ft AGL as slow as safely possible, it was amazing how hard it was to spot the dummys when the instructior pointed them out to us. (And they where sitting on high ground, without vegitation.
Pilots on this forum mock hi-wiz wests and it's use at the airfield. I kind of agree, but I carry one in the aircraft, if only to have it available post forced landing!
Looks bleak for Mr Fosset