Interesting idea, but as the aircraft will use only a single ID and a single callsign, this will help only against a causal observer.
Most (all?) of the „callsign providers“ assign a random number for each flight or make you choose one from a list during filing.
You can still track the aircraft using the ID. If you’re really interested (e.g. corporate intelligence) tracking several flights can give you a good idea of who the operator is. Metadata is sensitive, too.
You can track any plane if you have a “spy” (or a webcam) at the departure airport, and capture the Mode S or ADS-B data as it takes off.
With the ADS-B Out mandate in the US, tracking of aircraft has become much easier, Companies like FlightAware provide enthusiasts with cheap ADS-B receivers that feed the ADS-B data to their servers. To the extent any privacy is offered, the PIA limits the ability to associate the call sign with an N number using the ADS-B receivers. One needs to use one of the methods suggested to determine the true identity of the aircraft, but just using the FlightAware system by itself does not disclose the identity. There are things that a PIA user can do to mess up the limited privacy, such as including the true registration in the filed flight plan, or using the same call sign when flying using the N number. Switching back and forth from using the N number or PIA or N number sign requires a maintenance operation to change the ICAO Mode S address. Most pilots won’t be able to change the Mode S Aircraft ID, even though it may be simple to do and it technically requires a maintenance operation.
tschnell wrote:
Most (all?) of the „callsign providers“ assign a random number for each flight or make you choose one from a list during filing.
Which call sign providers do this? The first three characters of a call sign are assigned such as FFL or DCM. There are 11,110 numeric values and many of these are permanently assigned to subscribers that may or may not use PIA, so it would be interesting if a call sign block of numbers could be used. The FAA does not use the call sign to determine the N number of a PIA aircraft, they use the PIA agreement to identify the actual N number if a SAR is required or a flight needs to be investigated for an infraction of the regulations. If someone went to the length that Peter suggested, this would not offer any privacy.
PIA is aptly named. It can’t be used over Oceanic airspace or any international flights. It restricts obtaining DCL via CPDLC and is a PIA when you have to switch back to a filing with an N number.
