The danger of airport walls

By Capt. G A Fernando MBA

gafplane@sltnet.lk

Former Chief Pilot B737-200, Air Lanka

Former Member CAASL Accident Investigation Team

Former Crew Resource Management (CRM) Facilitator Singapore Airlines

Designated Flight Operations Inspector CAASL.

President, Aircraft Owners and Operators Association Sri Lanka

On the night of 7th August, 2020, Captain Deepak Vasanth Sathe and First Officer, Akhilesh Kumar, were approaching land at the Calicut International Airport, during heavy monsoonal rain, in a Boeing 737-800 aircraft, operated by Air India Express. The aircraft, registered as VT-AXH, was carrying out a repatriation flight IX-1344 from Dubai. Capt. Sathe was an ex-Indian Air Force pilot.

It is too early to know what exactly happened. Under bad weather conditions, such as this, the pilots will attempt to fly solely with reference to instruments, with little or no outside visual clues. The flight deck lights will be dimmed. Only one pilot is allowed to handle the controls and is designated as the ‘Pilot Flying’ (PF) and the other one is designated as the ‘Pilot Monitoring’ (PM). Their heads (and eyes) will be inside the flight deck, monitoring the flight and radio navigation instruments, with the Autopilot(s) on, to about 1000 feet, above the airport altitude, where the PM will announce “1000 feet” while looking inside, will now also start to look outside for visual clues with the windscreen wipers switched on. The PF must acknowledge that call. At a 100 feet, above a specified minimum altitude, depending on the airport and the type of instrument approach carried out, the PM will announce again loudly “Hundred above” The PF must acknowledge with a “Roger”. If the PF doesn’t do so at 1000ft or 100 ft, the PM will announce for the second time  If there is no response, then it is assumed that PF is incapacitated in some way, and the PM will ‘abort’ the landing approach and carry out a go around. Once at a safe altitude he will ensure that the auto pilot is on and check on the wellbeing of the handling pilot.

As can be seen from the above, it is a matter of close teamwork, standard call outs and procedures that enable pilots to land in bad weather. It is reported that the operating crew of Flight IX-1344 initially approached the runway (2845 meters/9330 feet long), from the opposite (East) side. They had initiated a ‘go- around’ at an altitude of 2700feet, which was well above the minimum altitude that they were allowed to descend to. We can assume that there was bad weather picked up on their Airborne weather Radar Display on their proposed approach path, which was unacceptable and may have opted to come on the less cloudy and rainy landing approach from the direction they did, even with a compromising tail wind of 10 to 15 knots. (a judgment call). Monsoon weather comes in cells of cloud and rain. Looking at their cockpit Radar display, pilots can easily analyse and decide on the better side to approach a runway from.

The last bit of the landing approach is critical after the ‘Hundred above’ call by the PM who will declare whether he has the runway lights in sight. At the minimum authorised altitude, PM will announce “minimums runway in sight” or “minimums, no contact” which will mean that the PF will have to go around. On this stormy night, the fact that they continued the approach and landed on the runway, successfully, showed that they had sufficient visual cues through the wind screen between the sweeps of the wipers, which create a major distracting, racket. In extreme conditions, the Flying Pilot will have about 1 mile (30 seconds) to decide whether it is safe to continue with the landing. There will be less time than that if the approach is downwind. They would have practiced approaches like this, many times in the B737 Simulator, to the satisfaction of an Indian Civil Aviation Authority Examiner.

Then comes a host of other problems. Is the beginning of runway (Threshold) crossing height correct? Ideally, it should be around 60 feet. Any height above that would mean that the aircraft would be touching down further into the runway than the recommended 1000 ft to 1500 ft, from the start. It again is a judgment call by the Captain. It was reported that the Calicut Air Traffic Control Officer saw the B737 -800 touching down quite deep. Even at this point the crew could have gone around if they felt uneasy. The pilots are trained to trust that ‘empty, something-is -not –quite- right’ feeling. After the touchdown, the Flight Crew will have to depend on the stopping devices (Reverse Thrust, Wing Spoilers and Wheel brakes) of the aircraft to bring the aircraft to a stop. Once these devices are applied, the Flight Crew will be committed to stay on ground.  Did they all work effectively? It was reported that there was standing water on the runway. It was also reported that the runway surface wasn’t ‘grooved’, to improve traction and drain the water.  Was the aircraft subjected to Hydroplaning? Hydroplaning is when a layer of water gets between the tyres and the runway surface resulting in no traction and stopping power. In fact it was reported that a survivor felt the aircraft accelerate after a few seco

nds on ground after touchdown. Jet aircraft of today are equipped with antiskid devices, but for that to work the wheels must spin first. So what is recommended to the pilots is to touch down firmly to dispel the thin layer of water between the tyres and the runway surface and let the auto brakes commence the braking action. However, if braking manually, initially the pilot must go easy on the brakes and progressively use maximum braking (foot pedal pressure). It is also reported that the engines were shut down. Did such action make the reverse thrust from the engines unavailable for stopping? The pilots could have used maximum reverse thrust till the aircraft came to a stop. (In some B 737 models pilots could even use reverse thrust to reverse from the parking stand without the aid of a tractor.) They could have even ‘cooked’ the engines by exceeding operating temperatures if necessary to save lives. The safety experts say that with reference to Flight Operations, the Captain should himself, (his own ability) know his crew,(How well did the Captain know his First Officer?), know his aircraft, (B737-800), know his mission (Flying passengers safely from Dubai to Calicut), and above all, factors that continuously evaluate the risks.(Rain, down- wind, should I continue the approach? wet runway, can I stop, safely?)

Were the pilots aware of their precarious situation? (ie) that they were going to overrun this runway. If so, at what point of time did they realise that they will be unable to stop. Only the recovered black boxes (Cockpit Voice Recorder and Flight Data Recorder) will be able to shed some light to the accident investigators. One thing we know for sure. The aircraft went down a slope and impacted a solid perimeter wall, killing both pilots and passengers. The force of the impact broke the aircraft in two.

Here is what one rescuer said “Most challenging was to bring out the two pilots. They were both found in an unconscious state. Because of the impact of the crash, the cockpit cabin got separated from the rest of the aircraft and had rammed the perimeter wall of the airport. The speed of the plane must have been very high because the cockpit cabin got stuck into the wall. Luckily, we found a JCB machine on the main road across the wall. It was used to demolish a portion of the wall. The firefighters and medical staff then used equipment to cut open the body of the aircraft to pull out the two pilots. Their rescue alone took close to an hour.

Their bodies were badly damaged. Both of them were rushed to the hospital without any delay,”

Most developed countries have perimeter fences instead of solid airport walls to prevent this sort of unfortunate accidents.

India is an exception. The Indian airport authorities are forced to have walls to prevent encroachment of cattle and the community who tend to use the airport premises as public open air toilets! In airports, like Mumbai, men and women, from the slums, in the vicinity, climb over the walls every morning, to do what they have to do, on the airport side. The walls act as a deterrent but create a safety hazard. On the morning of 12th October ’2018 a Boeing 737, departing Triruchinapoly, Kerala, India, for Dubai, UAE, hit the perimeter wall on departure, but was miraculously saved.

Every year, during the monsoon time, runway overruns and other occurrences, in India, are frequent. This year, there were six occurrences in India alone. On 29th April 2020, SpiceJet Boeing 737- 800 in a place called Shirdi; 30th June’2020, in Mangalore. Air India Express; 30th June, another smaller SpiceJet DH dash 8 in Surat; 1st July 2020, a SpiceJet Boeing 737-800 overran the runway, in Mumbai; 1st July ’2020, there was  a hard landing of Air India Express B737.-800 in Calicut; 2nd July 2020, another SpiceJet almost veered off the runway, running over some runway edge lights. In Kolkata. The last being the fatal accident B 737-800, on August 7th 2020.

The weather, in the Western Coast of Sri Lanka, is Identical to that of Kerala, during the South West Monsoon. There is a similar safety hazard, at the Galle Road end, of the Ratmalana Airport. The wall was introduced by the SLAF, during the time of war, to prevent public peering into the airport which posed a greater risk than losing an aircraft with passengers on an overrun (excursion) and the subsequent impact with the concrete wall. Since the situation has now changed, the SLAF has no problem if the wall is removed. An essential part of ‘Safety Management’ is learning from accidents committed by other Operators. Runway over runs in intense rain, don’t only happen to others but could occur in our own back yard. For over eight years this writer, and many others, have been trying to convince the authorities that this solid Concrete wall is an accident waiting to happen and should be replaced by a fence, as in other airports of the world in keeping with international safety standards. Unfortunately, there are three ‘co-owners’ of the concrete wall. The Civil Aviation Authority Sri Lanka (CAASL), Airport and Aviation Ltd, Sri Lanka (AASL) and the Sri Lanka Air Force (SLAF). This was pointed out as an unnecessary hazard to air operations at many Policy Development Meetings at Temple Trees. The SLAF said they had no objection for its removal (since the 30-year war was over). Although the AASL was standing by for its removal, the CAASL was ‘foot dragging’

After the B 737 incident in Triruchinapoly, India, 27 very Senior Pilot Instructors and Designated Flight Operations Inspectors (totalling flying experience of 330,500 flying hours) forwarded an appeal to the then Director General of the CAA requesting him to remove the wall as it created a definite safety hazard to operations at the Ratmalana.

Later, on a further appeal by the Aircraft Owners and Operators Association, Sri Lanka, the New Director General of the Civil Aviation Authority declared that he has no objection for the replacement of the solid wall with a fence. The AASL is now proceeding to check with the Ministry of Defence (MOD) again for concurrence. The merry-go-round continues. The advertisements on the said wall may be the problem as millions of Rupees have changed hands. Thus putting a price tag on air safety.

It seems strange that in a country where the authorities have removed the walls of Police Stations without hesitation, we are unable to remove this hazardous wall. Are we waiting for a fatal accident to happen in our neck of the woods?

“IF YOU THINK THAT SAFETY IS EXPENSIVE, TRY HAVING AN ACCIDENT”

— Jerome Lederer Flight Safety Foundation