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SAFE SKIES

Indian aviation’s clouded vision

Photos: Tomas Cubero, Captain A. Ranganathan.

Crucial minutes: A U.S. Airways flight taking off in torrential rain in Costa Rica; (below) the view from the cockpit 12 noon on a stormy day.

The modern Indian fairytale will read: “Once upon a time there lived a man called Mahatma Gandhi. On January 30 and October 2 every year, our leaders will think of him. Gandhi lived and died for Satayameva Jayete. He believed in trust and despi sed greed. In July 2008, our politicians destroyed the meaning of trust. And recently, greed destroyed the meaning of Satyam. During the past few years Indian aviation flew high and God has been very kind in spite of several serious failings. We all live happily ever after”. Like Humpty Dumpty, trust and truth lies shattered and can all the king’s horses and all the king’s men put credibility together again? The day is not far of before God loses his patience. He may, like all the Indians clamouring for action, decide that “enough is enough”.

Standard & Poor is the world’s foremost provider of independent credit rating, indices and risk evaluation. But, the poor safety standards maintained by our aviation system are not likely to get anything but an unsafe rating. When one evaluates the risk perception, it may not be a surprise if God turns a blind eye. The International Civil Aviation Organisation (ICAO) has set the norms that civil aviation goes by. In the ICAO Annexes, Standards are mandatory and Recommendations are left to the discretion of a country to implement them.

The monsoons are just a few months away. The time is right to reflect on July and November of 2005. On July 31 of that year, an Air India 747 overshot while landing on a runway that was contaminated with slush and the authorities opened a runway for operation when it was in an unsafe condition. During the deluge in November 2005 at Chennai, a private airlines flight landed on the flooded runway in tail wind conditions. The pilot should not have attempted the approach in dangerous conditions. Fortune favoured both flights. In 2008, the mandatory runway maintenance schedules were bypassed in major airports. Mumbai and Kolkata runways had not carried out rubber removal as per the ICAO schedules. Commercial considerations for the airport and airline owners superseded safety requirements. The regulator was a silent spectator!

Aviation is a very precise subject. An error of a few millimetres or seconds can make a difference between safety and accidents. Safety studies over the years have identified the measures required to make aviation safe. Design of aircraft and their instrumentations have taken human factors into consideration. Modern aircrafts can be flown to very precise figures — speeds, heights, profiles etc. An aircraft landing or taking off has to be flown to the accurate numbers. They are travelling at nearly 175 feet per second and a delay of a few seconds in the reaction of the pilots can make a difference in the safe conduct of the flight.

Every take-off or landing is based on the correct and accurate information being given to the pilots. The distance that the aircraft is going to cover during these manoeuvres is calculated by the pilot because he believes that the numbers given to him are true — the weight of the aircraft for the flight given to him by the ground staff, the runway and weather conditions given by the Air Traffic Control based on the inputs received by them. Procedures and rules have been evolved taking the dynamic nature of the flying. While a margin is inbuilt for calculations of take-off and landing due to the dynamic nature, the margins for runway conditions reporting are vague and this has often been the factor in accidents in adverse weather.

In tropical conditions like what we encounter in India, rain is the major factor. Operating flights in heavy rain emphasises the importance of numbers and runway conditions. Flight manuals mandate the numbers to be flown by the pilots. The performance Regulations restricts the precise weight of the aircraft allowable for a particular condition and allowances are made for human factor errors. For example, when a runway is reported to be “Wet”, operational calculations are based on the amount of water being less than 3mm on the runway surface. When it exceeds that figure, the condition is based on what is termed as “Contaminated or Slippery”. When the amount of water exceeds 13mm on the runway surface, take-off and landing are not permitted.

The data given by the manufacturers for take-of and landing distances are based on the numbers flown by extremely experienced test pilots. The distance data obtained from the test flights are multiplied by a figure of 1.67 to allow for human factor errors — the experience levels and the flying skills of average pilot. This figure applies when the runway conditions are DRY. When the runway is reported wet, this corrected figure is multiplied by 1.15 to allow for additional safety margin. Hence, a dry runway figure is multiplied by 1.92 times to cater for a landing on wet runway, almost double. Thus, an aircraft which requires 3,000 feet of runway to stop in dry conditions will require 6,000 feet of runway when it is wet. When the conditions are contaminated or slippery, the required distance is far higher.

The data for wet runway is based on precise actions by the test pilot. A perfect landing at 1,000 feet from the beginning of the runway at a precise speed, an immediate application of brakes within ONE second and deployment of Thrust Reversers and Spoilers within TWO seconds of touchdown. Spoilers are the panels which move up on top of the wing to increase the drag and put all the weight on the wheels to improve braking action. The average pilot is unlikely to match these numbers. The margin of 1.92 is calculated to cater for the performance of an average pilot.

In adverse weather conditions, speeds are likely to vary due to wind conditions and also the flying skill of the pilot. Every knot of additional speed (approximately 2 kmph) means that the aircraft is likely to cover an extra 175 feet. The extra speed would also result in a touch down later than the calculated point as the aircraft will float over the surface. During an approach in heavy rain, the visual illusions due to the film of water on the windscreen, in spite of the powerful wipers that aircrafts have, can play an additional part in judgment errors. The fatigue factor of the pilot comes into play when you consider the precise numbers that are required for take off and landing in rain. Unfortunately, the regulators and airline owners do not take this into consideration when rules are violated or misused. Moreover, the runway conditions during rain are mostly reported as “Wet” while, in reality, the conditions are flooded during a heavy downpour. The pilot takes off or lands in the belief that the depth of water is only 3mm !

For safe operations, the ICAO has mandated that the standards mentioned in Annex 14 are complied with. The runway surface condition is the key to safe operations. The maintenance schedule is clearly stated in the ICAO Annex 14 and related documents. The equipment to be used for validation with the ICAO documents are also clearly mentioned. No deviation is permitted as per the standards.

The Airports Authority of India, the guardians of our airports, fail to understand the requirement to follow the ICAO documents. They seem to follow the 2002 Indian Roads Congress report! The report has said rubberising Indian roads would provide better grip for tyres and avoid skidding of vehicles besides having other benefits such as longer road life and less maintenance expenses. It ensures at least 50 per cent more service life than normal bitumen on the roads. Runways are not roads. Rubber on the runway is dangerous, especially when wet. It has to be removed regularly and the friction coefficient of the runway has to be done as per ICAO Annex 14 standards. AAI has failed on this front.

The condition of the tyres is important for traction. A bald tyre is dangerous, both for aircrafts and cars, when the conditions are wet. However, for the requirement of runway friction testing in wet conditions, a smooth tyre is what ICAO requires. Several experts have pointed this out to AAI and the DGCA. The green pages of Annex 14, the bible for runways, clearly states that fact. Grooved tyres are used only for testing on snow covered runways. In India, we do not come across this condition except in the Himalayan region airports. All operations stop in those airports when they are covered in snow. Yet, based on a manufacturer’s recommendation, AAI uses grooved tyres whose test results inflate the friction value and is not approved for validation with the ICAO Annex 14 tables. The regulator remains a silent spectator in this serious lapse, as well.

After a spate of runway overrun accidents worldwide during the last three years, new regulations and procedures have been instituted in the international scene. We are yet to implement any of those recommendations or procedures in India. The regulator and the airlines merely go through the motion of adverse weather operations training. The procedures are to be completed during the simulator training. The training and proficiency check profiles are so long that it is impossible to complete a majority of the required exercises. Crew who have not really experienced flying in monsoon conditions in the type of aircraft they fly, are pushed into the scene.

Safety information is shared and disseminated world wide. We learn by sharing knowledge and experience. That is the only way safety can be enhanced. Gone are the days when punitive action against human errors were taken. In today’s aviation world, the emphasis is on how to mitigate and prevent a recurrence. In 2000, the Flight Safety Foundation (FSF) along with a host of safety experts, introduced the ALAR (Approach and Landing Accident Reduction ) project. The objective of the project was to reduce accidents by 50 per cent in five years. A Toolkit was distributed worldwide to spread the message.

The FSF is in the process of reviewing and modifying the ALAR toolkit with lessons learnt from recent accidents and incidents. In India, we started the ALAR project in right earnest in 2001. An adverse weather operation training kit was brought out as part of the project. Our work was appreciated worldwide. As it happens in India to any progressive project, it has died a natural death. Only time will tell if our aviation will have a fairytale ending or a tragedy in the coming monsoons.

Safety studies have established that the majority of the landing accidents have happened at night or when carrying out what is called a non-precision approaches. During periods of heavy rain, day becomes night! All the images used along with this article are taken in the time between 1200 noon and 2.30 in the afternoon. The image from Costa Rica shows the water depth is definitely many times 3mm! Pilots fly in the belief and trust that the runway conditions reported to them are accurate. Most of the time their judgment and skill helps. But, at times, like a Russian roulette, the unlucky one gets the bullet.

The DGCA and AAI have to get their act together on runway safety. As the marketing wizard Jay Abraham said “An amazing thing, the human brain. Capable of understanding incredibly complex and intricate concepts. Yet at times unable to recognise the obvious and simple”. An accident is staring in your face. It seems obvious to everyone except to people who run those organisations. Will the Gods decide that enough is enough?

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