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Loggings => VHF/UHF Logs, including satellites and radiosondes => Topic started by: alleycat on February 07, 2021, 2136 UTC

Title: ADS-B ID discrepancies
Post by: alleycat on February 07, 2021, 2136 UTC

I just got ADS-B software up and running on my RPS1A. I notice route discrepancies between the software it uses (Virtual Radar Server) and other information sources. For example, for Jetblue flight 634 (7 Feb 2021), I observe the following:
 - Virtual Radar Server (Ver. 2.4.4.36598) identifies origin as San Francisco & Destination as Boston
 - FlightRadar iPhone app identifies origin as Port-Au-Prince & Destination as New York (JFK)
 - FlightAware.com identifies origin (Port-Au-Prince, Haiti) & Destination (Syracuse, NY) [these appear to be correct based on the flight track]

So why the discrepancies, and who do I believe? Thanks and happy monitoring!

Title: Re: ADS-B ID discrepancies
Post by: cj468 on February 08, 2021, 1922 UTC

From Google and FlightRadar24 it looks like JBU634 is scheduled Port-Au-Prince -> JFK. On 7-Feb it seems it diverted to Buffalo before continuing later to JFK.

I used to be a big VRS user. It relies (or did at the time) on community input  for route information. There was/is a web page where route info can be submitted. Routes on that system can be wrong / out of date especially around the time schedules switch from summer to winter timetables and vice versa, particularly for charter and seasonal flights. I guess no-one has submitted an updated route to Andrew (VRS owner/developer) for JBU634.

Update: The VRS route info site is still there (https://sdm.virtualradarserver.co.uk). It has been expanded to cover airport and airline codes as well as route data. You need to set up an account before you can submit data. There is a facility to show route history for a flight number ... For JBU634 the route SFO>BOS is shown coming from ACARS data on 2013-02-20 and has never been updated.

Title: Re: ADS-B ID discrepancies
Post by: alleycat on February 09, 2021, 0249 UTC

Thanks for the enlightenment! I too saw evidence of the flight diverting from JFK to Buffalo, but that doesn't make sense, because Buffalo is *way past* JFK if you're flying from Port-au-Prince!

Title: Re: ADS-B ID discrepancies
Post by: cj468 on February 09, 2021, 0913 UTC

Sometimes FR24 seems to 'guess' at locations. Locally here, helicopters based at Redhill are shown as going to/from Gatwick, exec jets going to Northolt show as Heathrow etc.

In this case though FR24, Flightaware and PlaneFinder all show JBU634 going to BUF so I guess it went there.