Regarding the Mode S EHS MMEL / MEL, what is the meaning of: “DAP required or not required for the intended route”?
The Mode S Enhanced Surveillance (EHS) DAPs will be required, by aircraft operating in French, German and United Kingdom airspace from March 2007. If an aircraft is starting from an country whose airspace does not require Mode S EHS and flying to another country, whose airspace also does not require Mode S EHS, then the aircraft may fly with Mode S Elementary Surveillance capability only – or with one or more DAP’s failed. This assumes, of course, that the fligt plan does not cause the aircraft to fly over airspace in which Mode S EHS is required.
