Question about Qatar Flight 713 on April 11th

Does anyone know why this flight would’ve been down at 1900 feet? I saw it and it was crazy low.

Mon 02:29:51 PM 39.5849 -77.3782 213° Southwest 459 528 **1,900 **Descending FlightAware ADS-B (KJYO)

Full altitude details:
flightaware.com/live/flight/QTR7 … H/tracklog

Thx!

Look at the surrounding data points and it is obviously a one-off data error.

Except for the fact that I personally saw it. There was no way it was at 30000 feet. Not as I’m reading the logo on the plane without trouble, not when it was so low I seriously thought “this plane is in trouble.” I’ll grant you 1900 may be an error…nut not too much of one.

Well, no. Aircraft don’t go from 38000ft to 1900ft then back to 38000ft in the space of 120 seconds; they would have a violent disagreement with physics if they tried. The surrounding data points say it was steady at 38000ft, not maneuvering.

The more likely explanation is that what you saw was a different aircraft, not QTR713. There is a particular class of data errors for passive listeners - as opposed to secondary radar - where noise can make an altitude message get associated with the wrong aircraft if there are a couple of aircraft within range that have ICAO addresses that are close (only a couple of bits different).

It’s odd to me that two aircraft from Qatar would pass over the same space in semi-rural Maryland at the same time. I completely agree on the physics part but the time it flagged the low altitude is the time I saw it flying low. Maybe it did record another aircraft’s altitude, but I know what I saw – I had no trouble at all reading the name on the bottom of the plane… QATAR. I have a photo clearly showing QATAR but I wish I’d gotten it lined up so you could see it over the houses. By the time I grabbed the camera it was already mostly past.

Anyway, thanks for the info. I’ll chalk it up to a weird occurrence and I’ll be grateful it didn’t have trouble.