Diwali Gift

Last night while returning from Kolkata, Hiro and I without discussing with each other felt an apprehension when we heard a feeble voice on the PA system from the cockpit of Jetlite flight S2 364 on our return to Bangalore. We were not sure whether it was the pilot or the co-pilot we heard. It was an otherwise uneventful flight; it took off on the dot and commenced its decent into Bangalore exactly 20 minutes prior to touchdown. I noticed the pilot making a correction in the flight path just before touchdown and that caused some unknown anxiety and before we knew what was happening, the plane landed on all its wheels with a massive thud. Every passenger must have let off a shriek or a scream involuntarily. It made quite a few jump off their seats, so hard was the landing.

I quickly thanked my engineering fraternity for having designed the fuselage and the hydraulic wheel suspension strong enough to take such a massive impact from a careless nincompoop of a trainee pilot. It was so strong that the pilot did not have to either fire the retro or apply the mechanical brakes. It lost all its power and speed in that instant of impact. On a very warm day, with the runway getting heated by continuous sunlight, the temperatures can reach dangerous levels. Had this kind of landing taken place on a hot afternoon, say in Jaipur or nearer home at Madurai, the tyres would have probably burst.

Obviously nothing like that happened, the very fact that I am writing this piece kind off endorses that all was well in the end. The co pilot must have been shaken too and tried to turn this to humor when he said that it was a bad landing not because of a trainee, but because Jetlite wanted to give a cracker of a landing as a gift on the eve of Diwali. With our heart in our hands, it sure was a Diwali gift, to our families, though!

One interesting fact is the speed at which the aircraft makes contact with the runway during touchdown. The velocity of approach can sometimes reach about 300 km/hour, and a great impact in the horizontal direction is imposed on tyres of the wheels. This impact is referred to as an accelerating impact. Upon landing, the surface of a tyre of a wheel sometimes melts to raise smoke.

The black tyre marks that you see on the head of the runway are nothing but molten tyre material which sticks onto the runway. This tyre material sticking to the surface can be dangerous as it can make other landing aircraft to slip on its surface, especially on a very hot afternoon or when it rains.

If you recall, in the recent past a Concorde caught fire while taking off and crashed. Investigation revealed that the wheels collided with a metal piece lying on the runway causing the tyre to burst and a broken part smashed into the fuel tank, thus starting a fire. Engineers are now working on a suspension system that will prevent a tyre from bursting even when it collides with an object on the runway.

While commercial aero planes are considered path breaking in the list of mankind’s inventions, the amount of carbon dioxide it releases into the atmosphere is phenomenal. On an average, aircraft emission accounts for 3% of carbon dioxide emissions; the most significant greenhouse gas. This figure is likely to reach a whopping 5% in the next decade.

Another interesting fact for those of you with a scientific bent, a 1.5 degree increase in the average day time temperature, because of global warming will thin the air to such an extent that the runway would be required to be extended by 17 to 20% for the aircraft to get the float to lift off. This means new runways will have to be built longer and existing ones extended with more fuel being burnt to get the float to lift off. It is indeed a vicious cycle. One can imagine the painful changes in design that this will entail. Most airports are built within city limits where no further expansion is possible and some like in New York and Hong Kong are built on the edge of the sea. There will be a time in the not so distant future when Airlines would settle for smaller payload aircrafts and carry less of cargo.

Back home, fire crackers lit during Diwali can be a source of air pollution as these emit toxic gases besides carbon dioxide. 95% of the crackers come from a town called Sivakasi in Tamil Nadu and this is a Rs. 1,600 Crore business. There is very little authentic research done on how much effect the crackers have on global warming, but it certainly leaves thick smog in the air and with the pre-winter chill, the plume tends to hang low for a long time making it terrible for all those who suffer from lung related diseases. What can be certainly avoided is the loud decibel level cracker bombs that can even cause an increase in BP and deafness. It is a good feeling when I hear the younger generation wanting to stay away from bursting these crackers and wanting to go green. We all must take an equal responsibility…Planet Earth is not ours to stake a claim…we have merely borrowed this from our children.

A relatively harmless but effective way is to light up the house with diyas, giving the dwelling a bright and elegant look. Celebrating Diwali is all about heralding triumph over evil, light over darkness and knowledge over ignorance. It is a time to reinforce friendship, unite society and bring the family closer. It was a pleasant surprise to see Barack Obama, recently conferred with the Nobel Prize for Peace, lighting the ceremonial lamp at the White House amidst the chanting of Vedic Mantras. Not to be left behind, Brown in UK, likewise participated in a similar function at London ushering an era of brotherhood through intelligent use of religion.

Cheers and Wish you all a very Happy Diwali.