A few months ago flights took off one after another to Delhi from Chennai airport as it usually happens during peak hour. Everything hinted at a perfect and uneventful flight for the pilots - the weather in the national capital was clear, there was no congestion near the airport and the airport was functioning well.
But, as the flights started their descend to Delhi, air traffic control informed that the airport is closed for a VIP movement and they have to divert. It was mayhem on air as many did not have enough fuel to circle around or to divert. Some managed to find space in Chandigarh, others went all the way to Jaipur while a few others frantically asked for a priority landing in Delhi itself.
Such scenes can be a thing of the past as Airports Authority of India (AAI) is planning to introduce a new system by which planes will not be allowed to take off if there is congestion at destination airports. And there will be several pre-determined alternatives , including timely warning if an emergency develops midway.
Air Traffic Flow Management is looked upon as the next big thing in an array of modernization programmes AAI is implementing at Chennai airport in a bid to make flying hassle-free for passengers and airlines.
The new system allows all major airports and airlines to share data on weather and flight movements across the country in real time so that air traffic controllers and pilots can plan journey efficiently.
"Flow management is going to be the next thing that we are going to take up at Chennai. This will avoid delays on air. Flights will be delayed on the ground if there is any problem at the destination airport. Interfaces of airlines, air traffic control centres and others will be networked across the country so that air traffic flow can be managed smoothly," said regional executive director southern region D Devaraj.
Flow management comes close on the heels of two other upgradations -- the performance-based navigation system that sets routes for landing and take-offs , and the air traffic control automation integrated radar that eliminates blind spots. These have made flying above 2,500 feet hassle-free across southern skies.
Now, air traffic flow management would bring together communication channels and interface of airports, radar, airlines and met department so that collaborative decisions could be taken to make flying safer and efficient, said Devaraj .
Air traffic control automation and networking of radar are a pre-requisite for flow management. Chennai flight information region covering the whole of south and oceanic space have implemented it recently. Delhi and Mumbai are going to integrate their radar very soon.
Once this is completed next year, the flow management systems installed at regions - Chennai, Mumbai, Delhi, Kolkata - will be connected to a flow management control centre most probably in Delhi. This centre will be networked with all interfaces of airlines, airports, air traffic control , meteorological departments across the country.
"The desired flight path and flight level and their availability would be easily known to the airline and the air traffic controllers on a particular air route when flow management is activated. If a particular level is not available , the system will prompt an alternative. This will help the pilot save fuel by avoiding air traffic congestion, weather turbulence and other problems," said a senior official of AAI.
It is estimated that flow management at six metro airports is expected to reduce air and ground delays by 2,387 hours in a year and a fuel saving of dollar nine million for airlines, says a preliminary study conducted by AAI.
In the initial stages the flow management will mostly benefit international flights that use EMARSH (Europe, Middle East, Asia and Himalayan Structure) routes. Soon it will be opened up for domestic flights also.
"It will be easy to include domestic flights into the ambit of the flow management when the system starts functioning," said an official. Majority of the international routes are aligned in the west east direction of the country and flights often face problems in maintaining vertical separation because of traffic congestion when they fly over Indian air space. When flow management is ready it will also help AAI provide same vertical separation throughout the same flight route.