“The investigators have reportedly heard the voice of a third person in the cockpit of the Airblue jetliner,” a source close to the investigation told Dawn on condition of anonymity.
The voice has been extracted from the Cockpit Voice Recorder, according to the source, and the investigators were looking into various possibilities and aspects.
The CVR, which is part of the ‘Black Box’, is a flight recorder used to document the audio environment in the cockpit of an aircraft. In order to record and document the audio environment, microphones are installed in the pilots’ headsets and in the roof of the cockpit.
The source said that the data of communication between the control tower and the pilot were available with the investigators. Dawn has also learnt that the pilot and control tower communicated with each other for two minutes and 25 seconds.
Two teams are currently investigating the air crash in which 152 people were killed. One of them is headed by Air Commodore Khawaja Abdul Majeed, president of the Civil Aviation Authority’s Safety Investigation Board. It is focussing on human factors, possibility of technical fault and weather conditions.
The second team, headed by Federal Investigation Agency Director General Zafarullah Khan, has been assigned the task of investigating the possibility of ‘sabotage’.
The source said that investigators were trying to determine why the aircraft drifted five nautical miles away from its original route. “The late pilot was very experienced and professional with thousands of flying hours under his belt; hence the fact that the plane strayed five nautical miles from the original route is also a cause for concern for investigators,” he said. The source said that six investigators were yet to hold a joint meeting.
When asked if there was a third voice in the audio recording of the cockpit, CAA director general Air Commodore (retd) Junaid Amin told Dawn: “I am not aware of the presence of a third person in the cockpit… you cannot judge from the audio whether there was a third person….”
No fault in Airblue aircraft
An analysis of the Black Box of the ill-fated Airblue aircraft which crashed on July 28 has revealed that it had no technical fault at the time of the accident.
In intimation to A-320 operators across the world, Airbus said there was no need to update the procedures or make fresh recommendations after the ED 202 crash because all flight systems were working normally before the aircraft slammed into the fog-covered mountains.
All 152 passengers on board were killed.
The advisory was based on a preliminary analysis of flight data recorder and cockpit voice recorder by Bureau d’Enquetes et d’Analyses.
A final outcome of the investigation may take months, but preliminary investigations have set the direction for the probe.
According to aviation experts, the Airbus communication implies that technical malfunctioning has been effectively ruled out as the cause of the incident and it is up to the investigation team constituted by the Civil Aviation Authority to determine if the crash occurred because of pilot error, bad weather, control tower fault or any other factor.
The cockpit voice recording readouts have also revealed that the pilots belatedly realised that they were flying into terrain. The first officer of the flight was heard screaming “Sir, pull up, pull up” moments before the crash.
This revelation has been supported by the findings of local investigators which show that before hitting the mountains the aircraft had climbed from 2,600 feet to 3,100 feet. The aircraft was circling for Runway 12, where it was to attempt visual landing.
Sources privy to the investigations believe the pilot got panicked after realising that he was flying into the terrain and had turned the autopilot ‘heading bug’ to the left at more than 180 degrees.
The aircraft, experts say, takes the shortest possible route in such situation and instead of turning left moved towards right.
Why did the aircraft go so close to the hills? Several explanations are being dished out, but the most commonly heard of in the aviation circles say that the pilot while circling for Runway 12 was on Flight Management Computer, but instead of following the prescribed route he had probably created a ‘visual circuit using place bearing distance waypoints’ that put him in the wrong place.
Insertion of place bearing distance waypoints is strictly prohibited by aircraft manufacturers because the Airbus FMC does not have a ‘fix page’ capability, wherein a defined distance can be superimposed on the existing route.
The standard instructions are that any route that is not supported by a ground navigational aid should not be used.
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