Karachi-Muhammad Ali Jinnah-Quaid-e-Azam

The investigation therefore, concludes that:
- Some internal malfunction of the Propeller Governor Part No. 8210-410 Serial No. 2490719 was the cause of experienced uncommanded auto feather. However, exact cause of the occurrence could not be determined.
- Continuing take off below V1 speed (104kts) after encountering engine malfunction and after takeoff raising flaps below recommended height (400ft AGL) lead to decrease in lift and unsustainability of flight.

The accident took place due to:
- Cockpit crew landing the aircraft through unstabilized approach (high ground speed and incorrect flight path).
- Low sink rate of left main landing gear (LMLG) as it touched down and probable presence of (more than the specified limits) play in the linkages of shimmy damper mechanism. This situation led to torsional vibrations / breakage of shimmy damper after touchdown. The resultant torsional excitation experienced by the LMLG due to free pivoting of wheels (along vertical axis) caused collapse of LMLG.
- The RMLG collapsed due to overload as the aircraft moved on unprepared surface.

It was determined that the left main gear partially collapsed after it suffered a bird strike (rapacious) on approach.

Factors Leading to the Accident:
- The aircraft accident took place as a result of combination of various factors which directly and indirectly contributed towards the causation of accident. The primary causes of accident include, ineffective management of the basic flight parameters such as airspeed, altitude, descent rate attitude, as well as thrust management. The contributory factors include the crew’s decision to continue the flight through significant changing winds associated with the prevailing weather conditions and the lack of experience of the crew to the airplane’s automated flight deck.
- The reasons of ineffective management of the automated flight deck also include Bhoja Air’s incorrect induction of cockpit crew having experience of semi automated aircraft, inadequate cockpit crew simulator training and absence of organizational cockpit crew professional competence and monitoring system.
- The incorrect decision to continue for the destination and not diverting to the alternate aerodrome despite the presence of squall line and very small gaps observed by the Captain between the active weather cells is also considered a contributory factor in causation of the accident.
- The operator’s Ops Manual (CAA Pakistan approved) clearly states to avoid active weather cells by 5 to 10 nm which was violated by the cockpit crew is also considered a contributory factor in causation of the accident.
- FO possessed average professional competence level and was due for his six monthly recurrent simulator training for Boeing 737-200 aircraft (equipped with a semi-automated flight deck). Bhoja Air requested an extension for his recurrent simulator training on 07th March, 2012. As per the existing laid down procedures of CAA Pakistan, two months extension was granted for recurrent simulator training on 09th March, 2012. The extension was granted for Boeing 737-200 aircraft, whereas the newly inducted Boeing 737-236A aircraft was equipped with automated flight deck. It is important to note that Bhoja Air did not know this vital piece of information till their cockpit crew went for simulator training to South Africa. This critical information regarding automation of the newly inducted Boeing 737-236A was not available with Flight Standard Directorate CAA, Pakistan as the information was not provided by the Bhoja Air Management.
- Therefore it is observed that due to the ignorance of Bhoja Air Management and CAA Pakistan, the said extension in respect of FO for simulator training was initially requested by former and subsequently approved by the latter. This resulted in absence of variance type training conformance of FO because of which he did not contribute positively in recovering the aircraft out of unsafe set of conditions primarily due to lack of automation knowledge, proper training and relying on captain to take remedial actions. This is also considered as one of the contributory factors in causation of accident.
- The Captain’s airline flying experience on semi automated flight deck aircraft and his selection for automated aircraft without subsequent training and monitoring to enhance his professional competence and skill, is one of the factors in causation of the accident.
- None of the cockpit crew member challenged the decision of each other to continue for the destination despite violation of Ops Manual instructions which is against the essence of CRM training.
- After experiencing the extremely adverse weather conditions, the cockpit crew neither knew nor carried out the Boeing recommended QRH and FCOM / Ops Manual procedures to handle the abnormal set of conditions / situations due to non availability of customized Boeing documents for Boeing 737-236A (advanced version of Boeing 737-200 series).

Finalization:
- The ineffective automated flight deck management in extreme adverse weather conditions by cockpit crew caused the accident. The ineffective automated flight deck management was due to various factors including; incorrect selection of cockpit crew on account of their inadequate flying experience, training and competence level for Boeing 737-236A (advanced version of Boeing 737-200 series), absence of formal simulator training in respect of FO for handling an automated flight deck, non-existence of cockpit crew professional competence / skill level monitoring system at operator level (Bhoja Air).
- The cockpit crew incorrect decision to continue the flight for destination and non- adherence to Boeing recommended QRH and FCOM remedial actions / procedures due to non-availability of customized aircraft documents (at Bhoja Air) for Boeing 737-236A (advanced version of Boeing 737-200 series) contributed towards the causation of accident. The inability of CAA Pakistan to ensure automated flight deck variance type training and monitoring requirements primarily due to incorrect information provided by the Bhoja Air Management was also a contributory factor in causation of the accident.

The cause of the occurrence was uncontained failure of the 2nd stage disk of LP compressor of Engine # 4 due to fatigue fracture which resulted in in-flight fire and damage to adjacent areas of right wing / flaps to an extent that flight could not be sustained.
The use of mishap engine beyond its manufacturer’s assigned life without assessment and life enhancement by the manufacturer was the cause of its uncontained fatigue failure.

Detailed investigation and analyses of the examinable evidence confirmed that the aircraft had developed some problem with its Engine No.2 (Right) immediately after takeoff which was observed by the cockpit crew as propeller feathering on its own. No concrete evidence could be found which would have led to the engine’s propeller malfunction as observed. The only probable cause of propeller feathering on its own could be the wear & tear of the beta valve leading to beta system malfunction. However, this anomaly at the most could have led to the non availability of one engine and making a safe landing with a single engine since the aircraft was capable of landing with a single engine operation. Some of the actions by the cockpit crew before takeoff and subsequent to the observed anomaly in the Engine No.2 were not according to the QRH / FCOM which aggravated the situation and resulted into the catastrophic accident.
The following factors contributed to the accident:
The aircraft accident took place as a result of combination of various factors which directly and indirectly contributed towards the causation of accident.
The primary cause of accident includes, inappropriate skill level of Captain to handle abnormal operation of engine No 2 just after takeoff, failure of cockpit crew to raise the landing gears after experiencing the engine anomaly, execution of remedial actions by FO before the attainment of minimum safe altitude of 400 ft AGL resulted in non conformance and non compliance of cockpit crew to OEM recommended procedures to handle such situations.
The lack of situational awareness and CRM failure directly contributed towards ineffective management of the flight deck by the cockpit crew.
The contributory factors include inadequate cockpit crew simulator training monitoring mechanism both at operator and CAA Pakistan levels in respect of correlation of previous / current performance and skill level of cockpit crew during the simulator training sessions along with absence of conduct of recurrent / refresher simulator training between two annual simulator checks in accordance with ICAO Annex-6 guidelines and CAA Pakistan (applicable ANOs) requirements for specific type of aircraft in a year.

- Weather conditions indicated rain, poor visibility and low clouds in and around the airport. The information regarding prevalent weather and the required type of approach on arrival was in the knowledge of aircrew.
- Though aircrew Captain was fit to undertake the flight on the mishap day, yet his portrayed behavior and efficiency was observed to have deteriorated with the inclement weather at BBIAP Islamabad.
- The chain of events leading to the accident in fact started with the commencement of flight, where Captain was heard to be confusing BBIAP Islamabad with JIAP Karachi while planning FMS, and Khanpur Lake (Wah) with Kahuta area during holding pattern. This state continued when Captain of the mishap flight violated the prescribed Circling Approach procedure for RWY-12; by descending below MDA (i.e 2,300 ft instead of maintaining 2,510 ft), losing visual contact with the airfield and instead resorting to fly the non-standard self created PBD based approach, thus transgressing out of protected airspace of maximum of 4.3 NM into Margallas and finally collided with the hills.
- Aircrew Captain not only clearly violated the prescribed procedures for circling approach but also did not at all adhere to FCOM procedures of displaying reaction / response to timely and continuous terrain and pull up warnings (21 times in 70 seconds) – despite these very loud, continuous and executive commands, the Captain failed to register the urgency of the situation and did not respond in kind (break off / pull off).
- F/O simply remained a passive bystander in the cockpit and did not participate as an effective team member failing to supplement / compliment or to correct the errors of his captain assertively in line with the teachings of CRM due to Captain’s behavior in the flight.
- At the crucial juncture both the ATC and the Radar controllers were preoccupied with bad weather and the traffic; the air traffic controller having lost visual contact with the aircraft got worried and sought Radar help on the land line (the ATC does not have a Radar scope); the radar controller having cleared aircraft to change frequency to ATC, got busy with the following traffic. Having been alerted by the ATC, the Radar controller shifted focus to the mishap aircraft – seeing the aircraft very close to NFZ he asked the ATCO (on land line) to ask the aircraft to immediately turn left, which was transmitted. Sensing the gravity of the situation and on seeing the aircraft still heading towards the hills, the Radar controller asked the ATCO on land line “Confirm he has visual contact with the ground. If not, then ask him to immediately climb, and make him execute missed approach”. The ATCO in quick succession asked the Captain if he had contact with the
airfield – on receiving no reply from aircrew the ATCO on Radars prompting asked if he had contact with the ground. Aircrew announced visual contact with the ground which put ATS at ease.
Ensuing discussion and mutual situational update (on land line) continued and, in fact, the ATC call “message from Radar immediately turn left” was though transmitted, but by the time the call got transmitted, the aircraft had crashed at the same time.
- The accident was primarily caused by the aircrew who violated all established procedures for a visual approach for RWY-12 and ignored several calls by ATS Controllers and EGPWS system warnings (21) related to approaching rising terrain and PULL UP.

The Pakistan board of investigations determined that the probable cause of this accident was a structural failure due to overload. The aircraft weight was 7,183 lbs at the time of the accident as the maximum load as mentioned in the operational manual is 6,300 lbs, which means 883 pounds above max gross weight. It is believed that during climbout, the tail and stabilizers detached due to overload conditions.