PIA AT42 at Gilgit on Jul 20th 2019, runway excursion on landing

Last Update: December 12, 2024 / 17:39:22 GMT/Zulu time

Bookmark this article

Incident Facts

Date of incident
Jul 20, 2019

Classification
Accident

Cause
Runway excursion on landing

Airline
PIA Pakistan International Airlines

Flight number
PK-605

Departure
Islamabad, Pakistan

Destination
Gilgit, Pakistan

Aircraft Registration
AP-BHP

Aircraft Type
ATR ATR-42

ICAO Type Designator
AT42

A PIA Pakistan International Airlines Avions de Transport Regional ATR-42-500, registration AP-BHP performing flight PK-605 from Islamabad to Gilgit (Pakistan) with 53 people on board, landed on Gilgit's runway 25 but overran the end of the runway and subsequencly skidded sidewards off the runway coming to a stop past the end of the runway with the right main gear collapsed. There were no injuries, the aircraft sustained substantial damage to right main gear, right wing and right engine.

No weather data are available (weather looks clear and dry from passenger video however).

The airline reported the crew skillfully regained control of the aircraft after the ATR skidded off the paved surface of the runway to some minor extent during landing.

Pakistan's Accident Investigation have opened an investigation.

On Jul 26th 2019 Pakistan's Authorities reported the occurrence has been rated a serious incident, an investigation has been opened by the accident investigation (unclear whether this refers to Pakistan's Safety Investigation Board SIB or not). While landing on runway 25 the aircraft slipped and performed a longitudinal exit. The aircraft came to a stop 41 feet past the end of runway 25. There were no injuries, the level of damage is still unknown.

On Dec 12th 2024 Pakistan's SIB released their final report concluding the probable causes of the accident were:

Primary Causes:

- Involuntary Runway Excursion (RE) due intentional high-speed Approach and Landing by PF.

- Failure to adhere to SOPs.

- Lack of situational awareness and anticipation resulting in inadequate decision making.

Contributing Factors:

- Lack of assertiveness by PM.

- Inadequate application of Crew Resource Management (CRM).

The SIB released following findings:

- PIA flight PIA 605 aircraft Reg. No. AP-BHP was a scheduled passenger flight from IIAP, Islamabad to Gilgit Airport.
- The aircrew was qualified, medically fit, current, and experienced for flying the aircraft to Gilgit.
- There was no reported abnormality in the aircraft, particularly any defect related to aircraft performance during Landing Roll.
- The aircraft loading was at 24.7% CG which was within limits with a TOGW of 18,600 kg.
- Weather at Gilgit was reported to be fair with no significant weather.
- Ground operations were uneventful.
- The Captain was PF while FO was PM for the flight.
- After Take-off AP was engaged at 260 ft RA.
- Upon crossing 1,900 ft RA, VS mode was engaged contrary to FCOM procedures. VS target was initially +400 ft/min which was increased to +1,700 ft/min and then +2,000 ft/min causing the Pitch attitude to increase to 15º and speed to reduce to 130 kt as opposed to standard climb speed of 160 kt.
- VS mode remained engaged till TOC.
- Crossing 13,200 ft, VS target was reduced to +700 ft/min, then + 600 ft/min and finally +500 ft/min; however, this still resulted in speed reduction to 178 kt.
- The cruise was done at FL165.
- During cruise, the minimum RA height was recorded to be 2,636 ft; however, this is acceptable as per PIA SOPs for Northern Area flights where minimum separation of 2,000 ft is mandatory due to mountains.
- For Approach to Gilgit Airport, Captain initiated descent with VS target at -600 ft / min.
- Captain elected to descend for Approach to the airport at higher than normal speeds reaching up to approximately 245 kt CAS rather than maintaining the standard descent speed of 200 kt CAS as per PIA SOPs.
- The anomaly in descent parameters was indicated to the Captain by the FO. However, the Captain did not take any corrective action and the FO did not make any further attempts to point out any discrepancies to the Captain.
- At 10.1 NM from R/W threshold, once crossing 7,630 ft AMSL, the EGPWS triggered an alarm for 17 s while the RA height varied between 3,000 to 3,500 ft AGL, however the Captain did not take any corrective actions. This alarm was triggered due to terrain but could have been avoided if the aircraft was maintaining correct speed as per SOPs.
- The aircraft levelled off at 2,000 ft AGL and the throttles were retarded to FI position where they remained till Landing.
- The speed reduced from 240 kt to 200 kt.
- Descent was resumed after disengaging AP.
- Crossing 700 ft RA, throttles were set to CL OVERRIDE position to increase drag.
- At 513 ft RA, the EGPWS alert was again triggered due to high ROD of 1,200 ft / min without any corrective action taken by the Captain.
- During base leg, the Captain announced increase in tail wind; surface wind at the time was reported to be calm but gusts were present. The maximum tail wind at touchdown was 4-5 kt.
- Due to higher altitude, the TAS of the aircraft was also quite high and with no attempt to reduce speed, the CAS could not reduce sufficiently for the aircraft to be brought to Landing configuration due which the aircraft flew base leg in clean configuration as opposed to the normal procedure of configuring the aircraft for Landing prior to base leg.
- During base leg, Captain asked the opinion of the FO regarding a 360° turn in the valley to reduce speed for attaining Landing configuration.
- The FO was apprehensive of making a 360° turn because in his opinion, the speed was too high for such a manoeuvre inside the valley. Moreover, he had no prior training or experience of such a manoeuvre in such a situation.
- Since the Captain had not paid heed to the FO’s observations previously and also because of the experience, seniority and instructor status of the Captain, the FO did not voice any opinion but left the decision to Captain.
- Captain, on not hearing any opinion from the FO, decided to continue with the Approach.
- At 488 ft RA and speed 184 kt, “Too Low Gear” warning sounded due to incorrect aircraft configuration. The same warning was again repeated after 6 s at 500 ft RA; however, no action was taken by the Captain.
- Captain initiated the base turn; however, it was not an academic pattern as the aircraft headed for R/W threshold at an angle of 10°-15° from R/W heading, instead of describing a circular arc.
- On initiation of base turn, 15° Flaps were selected at 175 kt (speed for 15° flap lowering: 180 kt) and at a height of 491 ft AGL.
- Immediately after selecting Flaps, L/G lever was selected to Down position at 442 ft AGL and at a speed of 174 kt, 0.57 NM from R/W whereas the speed for lowering L/G is 170 kt.
- EGPWS warning triggered without any reaction from the Captain as aircraft crossed 500 ft AGL with gears still not down and locked.
- The Flaps came down to 15° position at 257 ft AGL.
- At a height of 230 ft AGL, the aircraft was put in a bank to align with the R/W for Landing.
- The gears attained down & locked position once the aircraft was rolling out in line with R/W 25 at a height of approximately 50 ft AGL and speed 162-163 kt.
- Just short of entering R/W threshold, EGPWS warning of “Too low terrain” was triggered at 55 ft AGL and ROD 800 ft / min without any action taken by the Captain.
- The aircraft was still in bank once entering R/W and straightened out on R/W heading at approximately 30 ft AGL.
- At no time during base turn or finals did Captain attempt a Go-Around.
- Full Flaps could not be selected as the speeds were too high once the aircraft entered R/W at 160 kt.
- Due to high speed, the aircraft tendency was to float for longer distance; however, Captain made the aircraft touchdown approximately 2,000 ft down the R/W at 150 kt CAS (GS: 170 kt) with 3,400 ft of R/W length remaining to stop the aircraft.
- Despite the higher Landing speed (more than 115 kt GS), Captain did not use Thrust Reversal and applied only brakes to stop the aircraft. The throttles were initially retarded to reverse but then placed just below GI position.
- Due to higher aircraft momentum as a result of higher speed, the brake application was insufficient to stop the aircraft on the R/W.
- To avoid going off the R/W, the Captain veered the aircraft to the right at 75 kt and then attempted to turn the aircraft anti-clockwise at 56 kt GS while advancing right throttle.
- Due to centrifugal forces at high speed, the aircraft could not be controlled and departed from the R/W surface.
- The unpaved ground added further stresses onto the MLG.
- As the Captain was attempting to turn the aircraft anti-clockwise while it was being pulled radially outwards, the Right MLG was already being stressed towards the outer side. Coupled with further stress from the unpaved ground, it ultimately collapsed.
- Due to the collapse of Right MLG, the aircraft suffered major structural damage.
- At this time, the engines were also running and the right engine suffered major damage once the propeller hit the ground.
- As the aircraft came to a stop Captain shut down the engines and then shut down all systems.
- Captain instructed the Cabin Crew to maintain stations as it was felt that there is no further immediate cause for alarm requiring immediate evacuation.
- All the passengers were subsequently evacuated safely from the aircraft.
- Post accident investigation revealed that the Captain was in habit of making high speed approaches and had done so on numerous occasions but without any undesirable consequences.
- The Captain had never been cautioned or reprimanded for violation of SOPs prior to the accident.
- FDA analysis and debrief was a neglected area at PIA as FDA debrief constituted only 5% of the total number of flights undertaken by PIA.
- Supervision of FDA debriefs by PCAA was also neglected and was not ensured despite PCAA being responsible for supervision of safety practices by PIA.
- As a result of the damage sustained to the aircraft during the occurrence, PIA took the decision for permanent retirement and de-registration of the aircraft.