Flight History
On 15 February 2018, Pakistan International Airlines flight PIA 585, an ATR 42-500 aircraft registered AP-BHP, departed Dera Ghazi Khan Airport at 04:10 UTC for a scheduled passenger flight to Jinnah International Airport (JIAP), Karachi. The en route flight was uneventful. Meanwhile, a formation of Pakistan Air Force (PAF) aircraft, three F-16s with call sign TIGER-1, were operating from Bholari to Bholari and returning from Masroor Training Area.
Communications and Traffic Information
At 05:22:21, TIGER-1 attempted to contact Karachi Approach but received no response. At 05:22:35, PIA 585 contacted Karachi Approach, who identified the aircraft and advised maintaining Flight Level (FL) 100 due to military traffic moving from right to left and maintaining FL80. PIA 585 acknowledged and indicated they had the traffic on TCAS. At 05:22:53, TIGER-1 again contacted Karachi Approach, reporting FL80. Karachi Approach instructed TIGER-1 to report ready for descent.
At 05:24:24, PIA 585 requested descent. Karachi Approach informed them of conflicting traffic at 2 o'clock, 13 nautical miles (NM), maintaining FL80, and advised PIA 585 to expect descent in about two minutes. PIA 585 acknowledged.
Radar Display Information
Karachi Approach radar depicted the following:
- At 05:25:29, PIA 585 was on a bearing of 082° to TIGER-1, range 5.8 NM, showing FL100 descending. Two of the three military aircraft showed FL77 and FL79 ascending.
- At 05:25:45, PIA 585 was on a bearing of 095°, range 3.6 NM, showing climb to FL101 ascending. Two military aircraft showed FL77 and FL75 descending.
- At 05:25:53, PIA 585 was on a bearing of 116°, range 2.45 NM, showing climb to FL102 ascending. Two military aircraft showed FL75 and FL76.
TCAS Resolution Advisory and Outcome
At 05:26:17, PIA 585 reported a Traffic Alert and Collision Avoidance System Resolution Advisory (TCAS-RA). Karachi Approach informed PIA 585 that the traffic had crossed behind them and later confirmed TIGER-1 was at FL50. At 05:27:27, Karachi Approach cleared PIA 585 for an ILS approach to runway 25L and descent to 3,000 feet on QNH. The flight then proceeded uneventfully and landed safely at Karachi at 05:38:00.
No injuries to crew or passengers were reported, and no damage to the aircraft occurred. All navigation and communication facilities were fully functional during the flight, and no significant weather was reported.