A Boeing 777-200LRMF converted freighter made an extremely low pass over Horseshoe Bay Resort Jet Center Airport on 24 June, coming within just feet of runway according to video and ADS-B data. The aircraft, registered N705DN, is a former Delta Air Lines 777-200LR that was converted to freighter configuration by Mammoth Freighters. The aircraft is currently owned by Jetran LLC and is scheduled to be handed over to Qatar Airways Cargo, reported FlightRadar24.
The data behind the flight
The lowest recorded altitude during the low pass by Flightradar24 ADS-B receivers was 950 feet. Obviously, the aircraft was much lower than 950 feet, so why the difference?
ADS-B altitude data is reported in 25 foot increments as the barometric altitude above mean sea level at standard pressure (1013.25 hPa or 29.92 in Hg). To know the height above ground level, it is necessary to correct for local pressure and take into account the elevation of the airfield.
Taking into account the local air pressure (QNH) at the time of 1018 hPa and the airfield elevation of 1,080 ft above sea level, the aircraft’s altitude is within the margin of error for ADS-B reporting of 0-25 feet. The close proximity to the ground is clearly seen in the video.
