The Hindu Business Line : When pilots qualify for sainthood

The saintly soul, Mother Theresa, is yet to be ordained as a saint. Her followers have to establish that she saved lives by performing miracles. Pilots, on the other hand, do not have to undergo this ordeal. Thanks to the media, both electronic and print, they seem to have already fulfilled the main requirement for sainthood!

Everyday, a couple of air-misses takes place over the skies of Mumbai or Delhi. And every other day, an aircraft has a bird strike. Sometimes, a well-known politician, famous cricketer or popular Bollywood personality is on board. And, lo and behold, a miracle takes place. They have a “miraculous” escape, scream the headlines. Every time a bird-strike or an air-miss takes place, at least 300 lives are involved. Unfortunately, saving these lives does not count as a “miracle” deed!

Bird control standards

The new International Civil Aviation Organisation Standards and Recommended Practices (SARPS) on airport bird/wildlife control became effective from November 2003. This standard seeks to identify those areas where universally applicable practices can be identified, and suggests levels of airfield habitat management, bird control equipment, manpower, etc. that an airport should put in place if it is to effectively manage the bird-strike risk to aircraft.

It is envisaged that these standards will inform airport managers, national regulators, the insurance industry, lawyers, etc., about what they should expect to see invested in bird/wildlife control at an airport. Airports with unusually high bird/wildlife strike risk are expected to, in the opinion of International Bird Strike Committee (IBSC), implement certain procedures and standards, irrespective of the movement frequency or type of aircraft involved.

Airports should conduct an inventory of bird attracting sites within the ICAO-defined 13-km bird circle, paying particular attention to sites close to the airfield and the approach and departure corridors. A basic risk assessment should be carried out to determine whether the movement patterns of birds/wildlife attracted to these sites means that they cause, or may cause, a risk to air traffic.

If this is the case, options for bird management at the site(s) concerned should be developed and a more detailed risk assessment performed to determine if it is possible and/or cost-effective to implement management processes at the site(s) concerned. This process should be repeated annually to identify new sites or changes in the risk levels at existing sites.

Where national laws permit, airports or airport authorities should seek to have an input into planning decisions and land use practices within the 13-km bird circle for any development that may attract significant numbers of hazardous birds/wildlife.

Such developments should be subjected to a similar risk assessment process as described above and changes sought, or the proposal opposed, if a significant increase in bird-strike risk is likely to result.

Political will

ICAO or IBSC may have standards and recommendations. But do we have the political will to implement the 13-km radius sterile area. Can we get rid of all the open garbage dumps or slaughter-houses? In these days of vote-bank politics, the Airport Authority of India has yet to clear the Dharavi slums in Mumbai. There is much talk of security risks and harassment of passengers boarding a flight. All it takes is a bird-strike conducive situation at one of these locations to bring down an aircraft.

One of the requirements for bird-control is to maintain the runway and taxiway surrounding areas clear of tall grass or vegetation. The maintenance is found wanting on most occasions. Every year, during the monsoon and post-monsoon season, birds flock to the airport area due to the abundance of grass. This, in turn, brings its share of several insects and reptiles, which form the main feed for the birds. In one of the major international airports, a bird’s nest was located right next to the runway. It took several compelling notes to get rid of the nest.

Most bird-strikes take place during the take-off and initial climb phase of the flight. This is the stage when the aircraft accelerates rapidly. The bird recognises an approaching aircraft and bases its escape manoeuvre based on its judgement of the aircraft path. Unfortunately, the bird cannot calculate the acceleration rate of the aircraft. This, often results in a bird strike.

Matter of judgment

The second reason is abrupt movement. The bird may even judge the path right and carry out its escape manoeuvre. But if the pilot decides to make his own manoeuvre at a very low level, the bird is caught napping. The third reason is the large engine air intake of modern jets. All these fan jets have a very large field of suction. The bird may not be able to judge this and gets sucked into the engine.

Experience is the only way a pilot can learn how to avoid a bird strike. A clear understanding of bird behaviour is required. Birds, when close to the ground, most often climb to get out of the path of an intruder.

Unfortunately, most pilots tend to try and climb over the bird and this results in the birds getting sucked into the engines. It takes a lot of initiative to keep the profile a little lower to duck under the bird, when height permits. The natural airflow over the wings will blow the bird away, keeping it away from the engines mounted under the wings.

The near misses

Air-misses take place mainly because the overcrowded skies force aircraft to be in close proximity. If all the radar controllers are qualified and all the pilots followed instructions strictly, the chance of a near-miss is remote.

All modern aircraft are fitted with “TCAS” (Traffic Collision Avoidance System). These are on-board computers connected to “Mode-S transponders”. When two aircraft are closing in on each other, the transponders talk to each other and calculate the closure rate. A “Traffic Advisory” is given out, both aurally and visually. The pilots are expected to look out and identify the conflicting traffic and make the necessary avoidance manoeuvre.

If the advisory is ignored or a wrong path is taken by either of the two aircrafts, the TCAS gives out what is called a “Resolution Advisory”. This comes out as a RED visual warning accompanied by an aural warning, giving out a clear instruction for a manoeuvre in the vertical plane.

The computer instructs the pilot to Climb or Descend, and a visual indication is positioned on the primary flight display. All that a pilot has to do is to follow these instructions implicitly.

At times, a pilot thinks he knows better, like what happened between a Jet Airways and an Indian Airlines flight a few years back, and they have a ‘miraculous’ escape! When a pilot ignores the TCAS instructions and follows an ATC instruction, like what happened to the aircraft over the Swiss control, a mid-air collision is the result. Traffic avoidance, go-around manoeuvres, engine failure, etc., are normal manoeuvres that highly trained pilots are expected to carry out.

A professional pilot is also trained to bring an aircraft down safely, even when an engine is severely damaged or it separates from the aircraft and falls off the wings. All modern passenger aircraft are built and certified to fly with several system failures.

If this trend of calling all these normal exercises a “miracle” continues, very soon the prefix of a pilot may change from “Captain” to “Saint”!

(The author is an airline pilot with 19,000 hours experience, and specialises in accident-prevention studies.)