Another example of the risk of relying on Mode C txpdr and TCAS for separation.
Yesterday out of CS, identified as normal, and happily climbing to F300 enroute GV. Somewhere in Class E, to the NW of CS, our friendly and probably scared ATCO calls and advises that he's lost our altitude readout.
A quick look and Claret & Reisling realise that the fork that dropped off the meal tray has inadvetantly knocked the txpdr alt selector to off.
Had this happened outside radar coverage, and in a busier environment, it could very well have been another hole of the swiss cheese lined up with the next.
