History of the Flight
On 4 March 2022, Pakistan International Airlines (PIA) flight PIA303, an Airbus A320-214 registered AP-BOL, operated a scheduled passenger service from Allama Iqbal International Airport (OPLA), Lahore, to Jinnah International Airport (OPKC), Karachi. The aircraft flew at Flight Level (FL) 380 along Air Traffic Services (ATS) route MIMAL–J112–NSH–KC. Simultaneously, a military aircraft designated GHAURI-62, a Hawker Beechcraft Corporation (HBC) aircraft, departed from Pakistan Air Force (PAF) Base Sharea Faisal (OPSF), Karachi, en route to PAF Base Nur Khan (OPRN), Rawalpindi, climbing to FL390 on ATS route OPSF–NSH–Z301–OPRN.
TCAS Resolution Advisory
At 06:51 UTC, GHAURI-62 contacted Karachi Area Control Center (ACC) East passing FL235 for FL310. One minute later, the controller trainee, in coordination with an On-the-Job Training Instructor (OJTI), cleared GHAURI-62 to FL390. At 06:56 UTC, PIA303 reported position ZOHAR maintaining FL380 and was cleared direct to MAKLI.
At 07:05:32 UTC, PIA303 informed Karachi ACC East of reciprocal traffic climbing through its level. At that time, GHAURI-62 was 20 nautical miles (NM) from PIA303, climbing through FL373 for FL390. At 07:06:15 UTC, the East Procedure Controller passed traffic information to GHAURI-62 regarding reciprocal traffic PIA303 at 9 NM maintaining FL380, and GHAURI-62 reported turning.
At 07:06:40 UTC, both aircraft reported a Traffic Alert and Collision Avoidance System (TCAS) Resolution Advisory (RA) approximately 30 NM northeast of Nawabshah. PIA303 initiated an RA climb to FL385, while GHAURI-62 initiated an RA descent to FL374. At the time of the TCAS-RA event, the vertical separation between the aircraft was 200 feet and the lateral separation was 6.2 NM.
Aftermath
Both aircraft proceeded to their destinations without further incident. No injuries were reported to any person on board either aircraft, and no damage was sustained by either aircraft. No significant weather was reported by the Meteorological Watch Office at the time of the incident.
Investigation
The Bureau of Aircraft Safety Investigation (BASI) Pakistan investigated the serious incident in accordance with ICAO Annex 13. The investigation determined that the incident involved a TCAS-RA event between civil and military aircraft. No probable cause was explicitly stated in the available report.