Calicut Crash – More Questions than Answers Remain

More than one month has elapsed since the tragic accident involving an Air India Express Boeing 737 NG aircraft that crashed while landing in inclement weather in Calicut. However, instead of answers, more questions about the crash remain.

Air India Express flight IX-1344 flying from Dubai to Calicut carrying 191 passengers, skidded off a tabletop runway, fell into a gorge and suffered catastrophic damage, or what is termed as ‘Hull Loss’ in aviation terms. Twenty passengers, including the two pilots, lost their lives.

Click the link below to watch a video that gives an accurate account of the accident. Video Courtesy – DW

No Preliminary Finding Report

Fortunately for the investigation, the ‘Black Box’, which comprises of the DFDR (Digital Flight Data Recorder) and the CVR (Cockpit Voice Recorder) were recovered undamaged from the debris. Analysis of these is fairly simple process for a technically qualified person. It was expected that the AAIB would come out with an official preliminary finding report, or statement soon after the accident.

However, no formal statement has been issued by the AAIB or the Probe Panel, leaving the door open for speculative analysis by unqualified ‘chair-borne’ experts on social media and even poorly qualified journalists.

Instead of acting with restraint and patience, many were eager to do their own analysis, and categorize the accident prematurely. The Director General of Civil Aviation himself suggested that it was probably a case of ‘Pilot Error’ even before the probe panel was set up. The statement was extremely unfortunate.

To read a post on a clarion call to reform the DGCA, CLICK HERE

Many senior pilots articulated their angst at this. Do read one such post which urges all to ‘Not Blame the Pilot Just Yet’, CLICK HERE

Formation of the Probe Panel

On August 13, a five-member panel was set up to probe the accident, headed by Captain SS Chahar, a former examiner on Boeing 737 NG. His team members include Mr Ved Prakash (Operations Expert), Mr Mukul Bhardwaj (Senior Aircraft Maintenance Engineer of B737), Group Captain YS Dahiya (Aviation Medicine Expert), and Mr Jasbir Singh Larhga (Deputy Director AAIB).

What was surprising was that the panel had only one member from the Aircraft Accident Investigation Bureau. The AAIB was set up primarily to carry out investigations in aircraft accidents, on similar lines of the NTSB in the USA.

The AAIB has a regular workforce of seven safety personnel and an independent panel of 23 pilots and cockpit crew, 12 engineers, four aviation operation experts, two experts each for aviation psychology and aerodrome and one expert each as In-Flight Safety personnel and air safety investigator. These 46 experts, that comprise of the AAIB were empanelled in October 2018.

Before the formation of AAIB on July 30, 2012, the DGCA used to investigate all the air accidents. However, a committee formed by the government in the 1990s, under the Chairmanship of Air Marshal JK Seth, stated that the DGCA couldn’t be a prosecutor, a jury and judge in a case against its own. International air safety norm also, to which India is a signatory, mandates the separation of investigation and regulation.

Human Factors

In the opinion of our contributors, an accident cannot be seen in isolation as a result of one causal factor. A catastrophic accident is a result of the a large number of variables all failing simultaneously, and thus aligning the ‘Holes in the Cheese’ (For more on this concept that was first conceptualized by James Reason, CLICK HERE)

Check out the following links to read the best books on Human Factors in Aviation

To read an opinion on whether it is acceptable to blame the pilots when they are not present to defend themselves, CLICK HERE

Calicut Runway and Environment

What must be investigated thoroughly is the environment in which the accident has occurred. The following points about the airfield merit thought:-

Calicut is a tabletop runway, close to the coastline. One may be able to understand a tabletop runway in a hill station, but right next to the coastline, why should a runway be located on a tabletop?

• Because of being a tabletop runway, there is no possibility to extend the runway length. Or maybe there is no political will to do so. Earlier plans to extend the runway ran into hurdles on account of the state government not being able to allocate additional land to AAI (Airport Authority of India). There are steep falls on both runway ends. The runway sides, called the ‘Runway Shoulders’ are also nonstandard width.
• Why cannot the runway be extended? To know more, CLICK HERE
• Due to the topography, approaches with Autoland (Landings carried out solely with Autopilot with no pilot inputs) are not recommended. Autoland approaches require the reliability of the radio altimeter which measures aircraft height over terrain and feeds it to the Autoland system.
• There were no (RESA) Runway End Safety Areas in Calicut earlier. (see image above) However, when RESA became mandatory at all airfields as per ICAO guidelines, the existing runway usable length was reduced to carve out a Runway End Safety Area. Thus, the runway usable length reduced from about 9300 ft to 8700ft. This was also not as per the mandated length and width. RESA is supposed to be at least 90m in length and at least twice the Runway Graded Width strip of 75m.
• The runway is not flat but has significant down-slope towards both sides with the highest point being close to the runway midpoint.
• There are no centerline lights on the runway that can help the pilot keep the aircraft in the center of the runway when landing in heavy rain or bad visibility. Runway centerline lights are a boon for pilots and mandatory to carry out Low Visibility Operations.
• The (ILS) Instrument Landing System was till recently only available on one runway end. But now is available for both runway ends. However, pilots have frequently complained of Glide Slope Fluctuations and inaccuracies while landing.
• As per many pilots, the Calicut runway surface is extremely uneven, and bouncy with rubber deposits on both the runway ends. This is significant as wheel lock and slipping tendencies (technically called Aquaplaning) tend to get aggravated in such conditions.

Meteorological Forecast

When all these environmental factors are combined with inclement weather, a recipe for disaster is already brewing. It is no secret that Calicut experiences extreme monsoon conditions.

There was heavy rain in Calicut at the time of the accident and the weather had been inclement for the last few days. Standing water on the Runway in case of a heavy downpour increases the chances of Aquaplaning. This is probably the core issue in the accident which has accentuated the deficiencies already present at the airfield. The probe panel must deliberate on the prevalent weather and the time of the crash.

The meteorological forecast which the pilots receive when they prepare their plan to land as compared to the actual weather is another story altogether. The accuracy of these forecasts is suspect at most times and pilots have to decide on / or revise their landing plans only when they come close to the airfield and assess the weather conditions on their own.

As per many senior pilots who have landed at Calicut, this is a routine occurrence.

Endnote

In the opinion of InformedAviator, a thorough look needs to be taken at the runway and airfield environment at Calicut. The probe panel needs to come out with a preliminary finding report, to keep a check on speculative analysis by unqualified and self styled experts.

What do you think about the accident? Please leave a comment and let us know.