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Old 10th Mar 2019, 09:20
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Old King Coal
 
Join Date: Aug 2000
Location: Monrovia / Liberia
Age: 59
Posts: 742
Originally Posted by bumpy737 View Post
Just took a look at Flightradar, it shows a climb to 8000ft, then a slight drop to 7600ft and a climb back to 8600ft where the data ends at a speed of 383kts...
I suspect that the altitude data you see on FlightRadar is being referenced to AGL, wherein HAAB has an elevation of 7,625 ft whereas FlightRadar shows the flight starting out at 0 ft.... therein if one adds 8,000 ft onto the airfield elevation it then makes more sense... and the 'dip' you see would then consistent with the crew switching their altimeter reference settings from the QNH (1029) in Addis Ababa this morning over Standard (1013), and with a published Transition Altitude of 14,000 ft. (i.e setting the altimeter reference from 1029 to 1013 has the effect of winding height off the altimeter, and I suspect that would show-up on the ADS-B as a change of altitude).

HAAB 100600Z 07010KT 9999 FEW025 18/09 Q1029
TAF HAAB 092130Z 1000/1106 09008KT 9999 SCT028 SCT090 BECMG 1007/1011 12008KT BKN026
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