Captain's Sleep Inertia Caused Mangalore Crash: Report
New Delhi, Apr 21: The report of the crash of the Air India Express aircraft at Mangalore on May 22, 2010, that was made public by the government on Wednesday, has stated that while the
New Delhi, Apr 21: The report of the crash of the Air India Express aircraft at Mangalore on May 22, 2010, that was made public by the government on Wednesday, has stated that while the Serbian-born foreign pilot Capt. Z. Glusica had slept for one hour and 40 minutes of the flight that could have led to sleep inertia, the (Indian) co-pilot H.S. Ahluwalia, who had complained earlier about another foreign pilot, did not try to wake up the pilot “probably due to such feelings”, reports Asian Age.
Both the pilots died in the crash which claimed more than 150 lives.
“During investigation, it came to light that First Officer (co-pilot) Ahluwalia had complained in writing about one foreign pilot to the management of Air India Express.
"Possibly, due to such feelings, the First Officer did not try to wake up the captain who was sleeping.
" It is evident from the Cockpit Voice Recorder that there had been practically no conversation between the two pilots for a prolonged period, made worse by the captain having slept for a considerable period,” the report states.
The report concludes that the cause of the crash was the pilot's (Capt. Glusica's) failure to discontinue the unstabilised approach and his persistence in continuing with the landing despite three calls from the co-pilot to “go around”.
The report also mentions that Capt. Glusica had “somewhat forced” co-pilot Ahluwalia to give an “affirmative” call despite the fact that the aircraft was not correctly positioned on the ILS Glide Path.
The report also cites several pilots as saying that Capt. Glusica was assertive and would display an attitude of “I am right”.
The report also said that the faulty landing of the pilot can be “attributed to fatigue, sleep inertia and the phenomenon of ‘get over with it'”.
The report also mentions that Capt. Glusica was counselled for an earlier “hard landing” in 2009 which had reportedly upset him.
The inquiry committee has recommended that Air India Express should carry out a detailed check into the background of foreign pilots in the future and also ensure 100 per cent preflight medical checks.
It has also recommended establishment of an independent Indian Civil Aviation Safety Board.
The report has blamed both the pilots for failing to carry out the required Descent Preparation Checks prior to descent in violation of the standard operating procedure.
The report also states that while the co-pilot gave repeated “go-around calls”, he did not take over the controls to actually discontinue the ill-fated approach.
Following are excerpts from the last-minute Cockpit Voice Recorder conversations seconds before the crash:
Co-pilot (6:03:35): It's too high!
(6:03:42): Runway straight down.
Captain (6:03:43): Oh my God Okay
Co-pilot (06:03:54): Go around?
Captain (06:03:56): wrong loc.. localizer
Co-pilot (06:04:06): Go around
(06:04:07): Captain
(06:04:12): Un-stabilised
(06:04:38): Go around Captain
(06:04:44): We don't have runway left
Captain (06:04:54): Oh my God
(06:04:59): awwww. Big One!
(06:05:00): Ohhhh
At this point, 6:05:00 am on May 22, 2010, the Cockpit Voice Recorder (CVR) went blank, reports The Indian Express.
The Captain, soon after touchdown, attempted to take off again against air safety norms and failed.
Few minutes later, Air India Express IX 812 overshot the tabletop runway at Mangalore's Bajpe airport, its right wing hit a concrete structure supporting the antennae, crashed into the boundary fence and fell into the gorge below.
The final investigation report has held the Captain's failure to execute a safe landing as ‘the direct cause of accident'.
The report, which has been accepted by the government, said Captain Zlatko Glusica, who was in command during take-off from Dubai and landing at Mangalore, carried on with the “unstabilised approach” during landing and ignored both the first officer's (HS Ahluwalia) three calls to ‘go around' and several warnings to ‘PULL UP' and ‘SINK RATE' from the Enhanced Ground Proximity Warning System (EGPWS).
Being at an altitude much higher than mandatory, the aircraft lost considerable runway length during descent, left with little to brake.
EGPWS alerts the pilots in case the aircraft is in danger of flying into the ground or an obstacle. Unstabilised approach means the aircraft did not follow the prescribed speed, descent rate or vertical/lateral flight path parameters at the time of landing.
Despite adequate rest period prior to the flight for him and the co-pilot, the Captain was found sleeping for the first one hour and forty minutes out of the total two-hour and five minutes recorded on the Cockpit Voice Recorder (CVR), the report said.
“As a result of relatively short period of time between his awakening and the approach, it possibly led to impaired judgement,” the report said.
The “sleep inertia” coincided with another phenomenon, often said to be a nightmare for pilots, Window of Circadian Low (WOCL) which refers to the period between 2 am and 5.59 am, when body temperature, alertness and ability to be awake is lowest.
The report observed that a mandatory pre-flight medical check was not conducted for the flight crew before they departed from Mangalore.
However, the report ruled out intoxication or self-administered drugs by the flight crew.
Another contributory factor, as per the report, was the incorrect landing instructions received by the flight as the Mangalore Area Control Radar (MSSR) was out of order and a notice to this effect was given in advance to all flights operating into or out of the airport.
There was lack of communication between the flight crew, and the CVR recordings show that first officer was not assertive when he made a call for ‘go around', even though he had read incorrect parameters during landing.
He said to the Captain, “Radar not available, but I do not know what to do.”
Giving its recommendations, the court of inquiry — headed by Air Marshal (rtd) BN Gokhale—has said that Air India Express should be allowed to function as in independent organisation, and its training and flight safety should be accorded due priority.
It also noted the airline's simulator, on which training is conducted, suffers from maintenance problems and frequently breakdowns.
It has asked the AAI to avoid downward slopes near the runway, as was the case in Mangalore, and instead bring them to the same level as the runway surface, especially in tabletop runways.
The regulator, Directorate General of Civil Aviation (DGCA), should formulate guidelines on controlled rest in the cockpit, the report said.