The Hindu Explains | What’s a ‘tabletop airport’ and what number of are there in India?


How can ‘tabletop’ airports be safer? Might the overrun at Kozhikode airport be averted? What are the measures that must be in place?

The story to date: On August 7, a Boeing 737 of Air India Specific (the low value subsidiary of nationwide service Air India) on a particular ‘Vande Bharat’ repatriation flight from Dubai to Kozhikode overshot the runway. There have been ‘174 passengers, 10 infants, 2 pilots and four cabin crew on board’. In what was its second try, flight IX-1344 touched down on runway 10 of Calicut Worldwide Airport at 7.40 p.m., went previous the runway finish and security space, and fell right into a valley. The fuselage break up within the influence. Each pilots misplaced their lives; there have been casualties and accidents of various levels amongst passengers. There was no fireplace on board. The Digital Flight Knowledge Recorder and Cockpit Voice Recorder have been recovered. The accident has as soon as once more turned the highlight on operations to what are known as ‘tabletop airports’ in India.

What’s a ‘tabletop airport’ and what number of are there in India?

Because the identify suggests, it’s an airport situated and constructed on high of a plateau or hilly floor, with one or each ends of the runway overlooking a drop. The airports within the nation which might depend as “tabletops”, are specifically Lengpui (Mizoram), Shimla and Kullu (Himachal Pradesh), Pakyong (Sikkim), Mangaluru (Karnataka), Kozhikode and Kannur (each Kerala).

Kozhikode airplane crash | Dying toll hits 18, probe begins

A retired aviation official says there isn’t a such time period as a ‘tabletop airport’ in any Worldwide Civil Aviation Organisation (ICAO) technical doc. However India’s statutory aviation physique, the Directorate Normal of Civil Aviation (DGCA), refers to those airports on this method by means of highlighting security measures throughout operations to those runways. The official provides that there usually are not many variations between a ‘regular’ airport and a ‘tabletop’ airport.

Why are these airports drawing consideration now?

Whereas there have been some aviation incidents at these airports, it was the accident in Mangaluru on Could 22, 2010, that highlighted operational dangers. Right here, an Air India Specific flight once more, from Dubai to Mangaluru, overran the runway whereas touchdown on runway 24. Flight IX-812 hit an antenna after which went down a steep embankment after which there was a fireplace. Of the 160 passengers and 6 crew, 158 misplaced their lives. The case centered consideration on the character of operations to such airports, particularly their shorter runways.

Kozhikode has two runways of two,700 metres in size. It was 2,860 metres however ‘shortened’ to accommodate a security function known as RESA, or Runway Finish Security Space (of 240 metres), which is a way “to restrict the implications when there’s an plane overrun throughout touchdown, a rejected take-off, and even undershoots the touchdown space”. In “tabletop” airport operations, the ICAO says a RESA of 90 metres is necessary, whereas 240 metres is recommendatory. The runways are Instrument Touchdown System (ILS) CAT 1 enabled and the airport has a spread of visible aids which embrace easy strategy lighting. As well as, all obstacles are lit. Each runways have Required Navigation Efficiency strategy.

Additionally learn | 2011 report flagged unsafe situations at Calicut airport

The retired official says there have been Code E plane (primarily based on wingspan) operations to Kozhikode airport. Kannur and Mangaluru too have had widebody plane operations. The most important plane at Kozhikode (and at any tabletop airport to date) has been Air India’s 423-seater Boeing ‘jumbo’ 747, working on the Kozhikode-Jeddah sector.

What have been the suggestions made after the Mangaluru crash?

In its report on the crash, the courtroom of Air Marshal B.N. Gokhale, former Vice-Chief of Air Workers, Indian Air Pressure (and its crew of aviation knowledgeable assessors) made a sequence of suggestions in a 191-page doc of October 2010. These have been addressed to the airline operator (Air India and Air India Specific). To the Airports Authority of India, it identified points like “avoidance of the downward slope within the overshoot space notably on ‘tabletop’ runways; the necessity for a floor arresting system for plane — such a facility is maintained at nearly all airfields of the Indian Air Pressure’; a visible reference system to alert the pilot (whereas touchdown) of the remaining distance to be lined; location of the ATC tower, strategy and space radars; the function of the Rescue and Hearth Preventing service, aerodrome danger evaluation and, lastly, suggestions for the DGCA.

Kozhikode airplane crash | A number of security suggestions have been heeded, says DGCA Chief Arun Kumar

Is there any ICAO doc on operations?

The retired official says there’s an ICAO doc 9981 for airports, which additionally serves as a suggestion for compatibility research of the operation of bigger plane in a relatively smaller aerodrome. The difficulty of progress versus aviation providers is a worldwide challenge requiring the event of small aerodromes for using larger plane in a secure method, particularly as demand for air providers grows from present airports. On this doc, the weather to be assessed embrace aerodrome infrastructure and its floor dealing with capabilities, and aeroplane traits. Every aspect is assessed technically to see whether or not these are suitable for brand spanking new kinds of plane proposed to be operated in such aerodromes. Thereafter, a correct security evaluation is finished to evaluate the danger related to the operation of upper class of plane. Danger mitigation measures are steered so as to carry these dangers inside “tolerable limits”. Such a compatibility research and security evaluation report shall be scrutinised by the regulatory aviation authorities and if discovered passable, the no objection certificates for operation of such increased class plane is issued.

When a necessity was felt to improve providers at Kozhikode, the airport undertook a runway recarpeting and strengthening train between 2015 and 2017.

Might security measures be higher when it comes to the bottom infrastructure?

Whereas RESA is in vogue, the time period EMAS has been tossed up, which is necessary in any respect worldwide airports in america. Known as Engineered Supplies Arrestor/Arresting System, it’s fabricated from engineered light-weight and crushable mobile cement/concrete.

Used on the runway ends, it acts as a security barrier and efficiently stops an plane overrun Its retarding impact will increase as one strikes away from the runway edge. In demonstrations within the West, it ensured good plane security. It should be famous that these are laid in simply replaceable blocks within the overrun space. The fabric is engineered particularly for the airport it’s for use, says the retired official. It’s stated to be perfect to be used in ‘tabletop’ airports. About 75m of EMAS can serve the aim of 240m of RESA with out inflicting any harm to the plane.

How are operations from a pilot’s perspective?

A senior airline commander, who can also be an teacher and examine pilot, says that in actuality, there isn’t a particular coaching that may be given for ‘desk high’ runways. Nonetheless, airways conduct route checks for brief runways. He says that one wants to grasp that the touchdown method and precautions taken are the identical for all runways besides that there isn’t a scope for error on quick and/or ‘tabletop’ runways. As plane accident information present, “runaway overshoots” (tour) happen as typically on non-‘tabletop’ runways. However in such circumstances, the plane, for apparent causes, has a significantly better chance of surviving. Nonetheless, an overrun by even just a few metres can flip catastrophic for ‘tabletop’ runway landings.

Throughout pilot coaching, the emphasis is on aiming for 1,000 ft from the start of the runway and touchdown throughout the landing zone. Pilots are additionally educated to execute a go round if they don’t make contact throughout the landing zone. Now, the senior commander says, there’s a whole lot of emphasis on this facet and pilots are requested to have this uppermost in thoughts whereas working on a brief or ‘tabletop’ runway . Additional, Crew Useful resource Administration is a compulsory coaching for all pilots following the suggestions made after the Mangaluru crash, which embrace classroom and simulator coaching. Right here, the senior commander says, emphasis is positioned on coaching the copilot to ask the commander to provoke a go round in case of an unstable strategy or if the plane has not touched down inside landing zone. She or he is even educated to take over as a final ditch measure in case the commander doesn’t heed the copilot’s security recommendation to provoke a go round. Aside from this, classroom coaching and simulator coaching are offered to elucidate numerous kinds of optical illusions together with these brought on by ‘tabletop’ runways. There’s a whole lot of coaching carried out on the simulator for touchdown in low visibility, heavy rain and winds. This occurs throughout preliminary induction coaching and each six months thereafter. Because the monsoon is a significant component in Indian aviation, monsoon coaching is given throughout preliminary command coaching earlier than launch. The senior commander provides that sure restrictions are positioned earlier than releasing the pilot in command for monsoon operations. Such complete coaching helps in any touchdown on any runway and may particularly be life saver in ‘tabletop’ operations. The DGCA has mandated a Monsoon Minimal Gear Listing so far as plane operations are involved. Right here it’s necessary that plane units utilized in braking or slowing resembling brakes and reversers are fully operational.

What’s the function of the air visitors management?

The ATC solely has jurisdiction to offer the pilots with climate situations together with visibility, rain and winds. The minimal visibility is already prescribed, says the senior commander. The ATC is not going to give clearance to begin strategy if visibility is beneath this minima, but when the visibility meets the necessities then the ATC can’t cease the pilot. The pilot commences strategy when visibility is inside minima and descends in direction of the runway to land. At some extent known as Determination Peak, or DH (usually round 200 ft) in case of ILS, and at some extent known as Minimal Descent Altitude, or MDA, in case of a non precision strategy, the pilot should concentrate on the runway surroundings so as to make a secure touchdown. If he has not, then he has to provoke a go round, circle and return for one more try at touchdown. Many a time, the runway can’t be seen even when reported visibility situations meet the necessities because the situations measurable on floor by the meteorological division usually are not the identical because the instantaneous situation on the strategy path. Solely a pilot can observe this.

So basically, after some extent, the ATC has a restricted function, says the senior commander.

If the declared visibility meets the prescribed minima, there’s nothing incorrect within the pilot making an attempt an strategy. However making an attempt to return in beneath DH and MDA, if the runway continues to be not seen is against the law, says the senior commander. No pilot does that, he provides.

One wants to grasp, he says, that in heavy rain, even when the runway is seen in time, generally on account of sudden burst of heavy rain throughout the ultimate landing, it is rather troublesome for the flight crew to positive tune their judgement of flare peak. This will even trigger a pilot to land past the landing zone. Lastly, he says, all airline corporations ask their pilots to divert in case of a thunderstorm and of their opinion if the climate is unsafe even when it meets the minima. But when there’s solely rain and no thunderstorm seen on plane radar then a pilot will try an strategy and take determination at DH/MDA.

What should Indian aviation do?

Aviation security knowledgeable Captain Mohan Ranganathan says India wants to maneuver away from the tradition the place, after each deadly incident, officers say runways will conform to ICAO requirements, the investigation will establish the accident trigger, and steps shall be taken to rectify the deficiencies. He says if the federal government is severe it must declare Kozhikode as a Code 3C airport, for under slender physique plane; ban landings on runway 10 throughout the monsoons; be sure that all runway situation requirements are enforced; guarantee strategy and touchdown accident coaching for pilots is enforced strictly and, lastly, be clear and safety-oriented and never take a look at industrial pursuits.

Supply hyperlink

Leave A Reply

Your email address will not be published.