Canada’s Transportation Safety Board (TSB) will not investigate an incident which saw Air Canada pilots receiving an erroneous ground proximity warning system or GPWS warning at 30,000 feet, asking the pilots to pull up.
According to an emailed statement to AeroTime, the TSB said analysis of the incident led to the conclusion that a comprehensive report was “unlikely to yield new safety lessons that will advance transportation safety”.
“Therefore, it has been classified as a Class 5 occurrence,” the TSB spokesperson added.
Per the TSB’s Occurrence Classification Policy, Class 5 occurrences “are not subject to comprehensive investigations followed by an investigation report”.
However, data is recorded for possible future analysis, statistical reporting, or archival purposes.
According to the TSB’s external public report of the incident, the Air Canada Boeing 777-200LR, registered as C-FIUF, was operating the regularly scheduled flight AC43 from Delhi Indira Gandhi International Airport (DEL), India, to Toronto Pearson International Airport (YYZ), Canada, when the incident took place on August 27, 2023.
“Approximately one hour into the flight, the crew received “terrain pull-up” warnings. The flight crew followed checklist actions and the decision was made to return to [DEL],” the report continued.
The Air Canada pilots declared a PAN PAN emergency and landed back at their origin airport, where emergency crews assessed the aircraft. After it was cleared to taxi, the Boeing 777-200LR returned to the gate without further incident.
None of the 316 occupants on board were injured in the incident, the TSB noted in the external public report.
The aircraft eventually departed DEL at 2:28 am local time (UTC -5.5) on August 28, 2023, landing at YYZ at 8:27 am local time (UTC +4). However, on that flight, the Boeing 777-200LR also entered into a brief five-minute holding pattern north of Peshawar, Pakistan.
The Triple Seven has continued to remain in active service since the incident, completing flights to various international and domestic destinations, including a return to DEL on August 30, 2023.