Ignorance and forgetfulness blamed for Malaysia Airlines’ flight emergency

A report almost four years in the making has found a Malaysia Airlines’ flight from Brisbane came very close to being a major aviation disaster.

The covers used to protect the pitot probes on aircraft while parked at Brisbane Airport. Picture: ATSB

The Australian Transport Safety Bureau has found forgetfulness, ignorance and a lack of diligence all contributed to what was almost a major aviation disaster at Brisbane Airport nearly four years ago.

On July 18, 2018, a Malaysia Airlines’ flight took off with all the aircraft’s pitot probes covered, which meant the pilots had no information about the A330’s airspeed.

The detailed ATSB report revealed no fewer than four people failed to notice or remove covers on the three pitot probes due to ignorance, lack of diligence or forgetfulness.

The red covers were put in place on the aircraft by a support engineer during a three-hour turnaround, to protect the probes from being blocked by mud wasp nests which are a potential risk at the airport.

Despite informing Malaysia Airlines’ own engineer the covers were in place, no data entry was made in a technical log to support this and the support engineer then left to work on another aircraft.

“There were effectively five walk-around checks required between the aircraft’s arrival and its dispatch, four of which did or should have taken place during the period in which the pitot probe covers were fitted,” the report noted.

“These were the engineering maintenance walk-around inspection, flight crew walk-around,

engineering pre-departure walk-around inspection and dispatch walk-around.”

Two of the walk-arounds were not done at all, while the Malaysia Airlines’ engineer saw the covers but then forgot to mention them.

During the flight crew walk-around a torch was shone towards the pitot probes but the pilot apparently did not see the covers which the report found lacked “conspicuity”.

Despite the major oversight, the aircraft still took-off from Brisbane without any airspeed information.

The ATSB report put that down to limited or ineffective communication between the captain and first officer when speed flags appeared on the A330’s primary flight displays.

“While independently trying to diagnose a rare and unfamiliar problem during takeoff, the flight crew experienced high cognitive workload, time pressure, and stress,” said the report. “This reduced their capacity to effectively interpret the situation and make a decision early enough to safely reject the takeoff.”

The flight climbed to an altitude of 11,000-feet as the pilots made urgent calls to Air Traffic Control and went through unreliable speed indication procedures.

These actions triggered the back up speed scale (BUSS), an optional feature on A330s that allowed the pilots to keep the aircraft flying safely in the absence of airspeed data.

The BUSS and assistance from ATC, eventually saw the flight return to Brisbane and make an overweight landing resulting in some damage to the aircraft.

None of the 215 passengers and 14 crew were injured.

ATSB chief commissioner Angus Mitchell said the various elements of the incident led to the agency undertaking one of its most substantive and complex investigations in recent years.

“The investigation illustrates how a range of individually straightforward factors can combine to nullify multiple critical safety barriers,” Mr Mitchell said.

A number of safety actions were undertaken by the various groups involved in the incident, from Airbus and Malaysia Airlines to the ground handling company Menzies.

The report said Malaysia Airlines now required the placement of a placard on the flight deck as a visual alert that pilot probe covers were in place.

“Airbus meanwhile has implemented additional flight crew training standards about unreliable airspeed on takeoff, added guidance on the importance of airspeed monitoring on takeoff and has begun a review of airspeed indications in A330 and other aircraft types.”