As investigators get to grips with the difficult task of determining the cause of this weekend's crash of an Air India Express Boeing 737-800 in Mangalore, a potentially big question has begun to emerge over whether the runway configuration meets with the relevant international specifications, reports aviation expert Chris Yates.
The Boeing 737 overshot the airport's hilltop runway as it tried to land
Runway 06/24 is the second and newest of the runways at the airport. It was commissioned in May 2006 and enabled the airport to handle larger and longer range jet aircraft than the existing runway. It has an overall length of 2450m and also features Runway End Safety Areas (Resas) of 60m length each.
With the available Resa apparently somewhat below internationally accepted recommendations the question now emerging is whether this fact contributed to the disaster.
International Civil Aviation Organisation (ICAO) Annex 14 'Aerodrome' recommendations (revised in 1999) states that a Category 4 airport with runway length of 1800m or more should have a Resa of at least 240m to provide a safe stopping distance in the event of an aircraft overshooting its touchdown point.
Anecdotal evidence from pilots who have operated to and from Mangalore Airport suggest that a touchdown overshoot of anything up to 500m is a recipe for disaster given the lack of available safe-stopping distance.
Much detailed investigation needs to be completed before this issue can be identified as a contributing factor to the loss of this airliner and 158 lives.
Runway redesign often takes time, frequently requires planning permission, needs to take account of environmental issues and costs significant sums of money. Changes cannot come overnight. With many major airports having been built many years ago, they are constrained by the availability of land in the surrounding area.
1. The runway at Toronto Pearson airport was noted for its limited Resa facility. An Air France jet that careered off the end of the runway is understood to have landed in poor weather prompting both overshoot and lack of traction.
2. Norman Manley International Airport, Jamaica and (6) Wellington International, New Zealand, are built such that the sea is at each end of the runway.
3. London City in the Docklands is restricted to aircraft with Short Take Off and Landing (STOL) capability given both runway length and environmental issues.
4. Funchal airport on the island of Madeira is partly built on concrete pillars driven into the seabed, given that it is land constrained.
5. Lugano, Switzerland, is constrained by the mountain ranges around it, which limits airlines to operating only particular types of aircraft suited to such operating conditions.
If it is proven to be a contributory cause, then the Indian Directorate General of Civil Aviation (DGCA) and the Indian Airports Authority (IAA) will likely be taken to task over why construction of this second runway was allowed to go ahead without due attention being given to the ICAO recommended Resa.
The International Civil Aviation Organisation (ICAO) is the responsible United Nations (UN) agency with control and oversight of the global aviation industry. It sets the Standards, Recommended Practices and Procedures (Sarps) that airlines, airport operators and air traffic control providers must either abide by or strive to achieve.
Principal guidance is embodied within the Chicago Convention and various amendments. While almost all signatory nations abide by the standards generated by the agency, questions continue to be raised about nations taking note of recommendations and how well compliance is managed overall.
While the principal signatories do abide by and actively apply the recommendations generated by ICAO, some apply them in time-scales measured in years. Others simply ignore them.
The agency is often perceived as toothless given its inability to police and effectively sanction nations that do not meet the Sarps.
Fit for purpose
In a fast-evolving environment such as the aviation sector, regulation often remains well behind the curve in relation to demand.
Many of the major airports around the world were established in days gone by and operate within the physical limitations they were either given or dictated by topographical conditions.
When an Air France jet careered of the end of a runway at Toronto Pearson (Canada) airport in 2005, it reignited the RESA debate. Similarly, an accident involving an American Airlines jet which nearly ended up in the sea at Kingston airport in Jamaica in 2009 added more fuel to the debate.
Whether the Mangalore crash was exacerbated by a short Resa or otherwise, this question should remain an issue at the very top of the safety agenda.
The International Federation of Airline Pilot Associations (IFALPA) has long raised this warning flag and continues to call for an extension of Runway End Safety Areas (RESAs) to 300m for all Category 4 airports.
Some countries, including Austria and the US have chosen to make the IFALPA recommendation the minimum, but very many others need to follow suite.
ICAO standards, recommended practices and procedures (Sarps) relating to runways are determined according to runway length using the standard Runway Code categories. Code 1runways are less than 800 metres long, Code 2 runways are 800-1,199 metres long, Code 3 runways are 1,200-1,799 metres long and Code 4 Runways are 1,800 metres or more in length.