Speed drop on flight


I have observed some trends. Sometimes when I observing a flight trail on flight aware I notice a plane might have a sudden drop and increase in speed. The seep can drop from say 850km/hr to 260km/hr within minutes and it shoots back to its former range. Is this caused by abnormality in flight data feed or it’s happening in real life?

I’m new to aviation analysis so I’d like to have a basic appreciation of the flights.


It’s a data error. Take a look at the detailed tracklog to see where it comes from (maybe it is e.g. a different data source)

(In this particular case, it look like it might be due to a combination of no direct ADS-B speed data being availble + a misordered position causing an artificially low speed estimate)


After some time watching, you’ll get a feel for what is plausible and what needs a second source.

A couple of days ago, I was watching this Emirates flight because a friend was on it. No other tracking site showed this dip and when my friend landed, reported that it didn’t happen.



This has happened again. This time it’s an upward twirl.