Nothing conclusive, but just some food
for thought re: SAR Aircraft - alarm/acknowledge policy, etc.
- An aircraft (usually) behaves differently from a ship, so some alert actions may be not quite appropriate or meaningful...
- According to ITU-R M.1371-4 AIVDM Type 9 should be transmitted by default every 10 secs, but it can be every 2 secs, "if during a SAR mission"... It would be interesting to know if there is actually a mission underway, but I did not find any indication of this in any message data.
- The specs also state that a SAR Aircraft can transmit static data via Type 5 or Type 24 A/B message, giving the call-sign, name/registration number, possibly dimensions, ETA, destination
etc. as well.
- The MMSI includes a hint if the plane is a fixed-wing type (111MID1xx) or a helicopter (111MID5xx)
- An aside: OCPN is quite tolerant on NMEA
format: spurious commas and lower case for checksum encoding ("0*2a" vs. "0*2A") is accepted, while some more strict decoders reject these sentences. I sometimes forget this and spend time again digging into the checksum algorithm... :-(
I use a very historic version of FlightGear for its operational simplicity and light footprint, but the modern versions feature truly amazing graphics...
A new version of Python UDP Connector is attached. It shows altitude from $GPGGA and includes some new capabilities.