The flight crew of an Airwork Boeing 737 freighter observed a 340-ft discrepancy in altitude readings between the captain’s and first officer’s display screens after departure from Perth, Western Australia, as well as small differences in airspeed and Mach number readings.
The June 10, 2022, incident occurred in reduced vertical separation minimum (RVSM)1 airspace, but the pilots did not inform air traffic control (ATC) of the problem, the Australian Transport Safety Bureau (ATSB) said in its final report, issued Thursday. The 340-ft discrepancy “exceeded the maximum allowed altimetry system error” and meant that ATC could not assure adequate vertical separation from other aircraft, the report added.
The incident came two days after a ground run during which the 737’s pitot-static probe covers were not removed and the automatic pitot heat was not shut off, the report said. As a result, the polyvinyl chloride covers melted onto the probes, and, al…
