Originally Posted by jabberwok
...I picked C-FMJO's Mode S code up at 1930 tonight (13th June) crossing the UK...
Hello Jabberwok:
By any chance were you able to determine if our aircraft was transmitting all of the additional Downlink Aircraft Parameters (DAPs) that are appended onto the end of the transponder emission using the 1090 mHz extended squitter protocol?
During development of the Series 400, we decided to fit Mode S EHS capability (ADS-B out capability) as basic to all the new production aircraft, because we believe that ATC surveillance using ADS-B will soon become very common in the remote areas where Twin Otters are usually deployed - more or less the same way that cell phone service brought telephony to areas that had never previously been served by landlines.
Only problem we have had is that no-one in our home neighbourhood (Vancouver Island) has equipment to pick up the extended squitter, and the only folks that do have the service (Nav Canada around Hudson's Bay) filter out replies from ADS-B out aircraft that are not registered with Nav Canada to use this service.
None of the ATC people we talked to enroute had the equipment necessary to monitor the extended squitter. The people around Southern England probably have it, but traffic was so busy we didn't dare interrupt to ask if they could detect our DAPs.
So - if you can observe DAP data, look for us to depart Farnborough around mid-day on Monday July 26th, destined for Altenrhein, CH (LSZR). I would be most grateful to know what you see - the aircraft sends out an amazing amount of information in the extended squitter, including Latitude-Longitude, Magnetic Heading, True Track Angle, Roll Angle, Barometric Pressure Setting, and even the altitude the pilot has entered using the altitude alerter.
Michael