Mode S
I know it's hopefully a way away yet and hopefully may yet be headed off at the pass but in anticipation I am interested in what we may be letting ourselves in for.
I gather there is only one suitable unit available yet for light aircraft - around £2.5K - £3K. Not being an avionics expert however I wonder what else is involved. I gather mode S will, in addition to altitude information, provide a unique identity and heading information. Presumably the call sign is programmed into the unit - not a big problem I guess, and the altitude provided in the came way as the current mode C units - also integral to the transponder. What about the heading though? Does this mean connection to the DI and potentially also having to fit new and compatable DI, or is heading information sourced in some other way? I am always concerned about the headline price of these units because this can be so misleading if other changes to the avionics panel are required so that the fitting / conversion costs end up being as much again!! Am I correct that the only additional information mode S provides is call sign and heading?
I would also be interested to know whether controllers feel mode S equipted light aircraft would help them, and whether their answer would be different depending on whether the aircraft was operating IFR or VFR. Finally, will both radar control zones and LARS units be equipted to interogate mode S transponders or only radar control zones. Presumably if the latter, mode S will be sod all good in open FIR!