Showing posts with label GBAS. Show all posts
Showing posts with label GBAS. Show all posts

Getting Mumbai, Delhi, and Bangalore, off the world's most delayed airports list

My post The world's most delayed and most punctual airports, seems to have ignited a media frenzy within India.

Times of India carried snippets from the article Sunday 11th January, which became a national story, and was picked up later that morning by the TV networks.

A lot of Bangalore Aviation readers have been asking me questions relating to the article.

Why are Mumbai and Delhi airports at the top of the list of delayed flight arrivals?

It is actually very simple. At both airports the number of flights arriving per hour exceeds the capacity of the runways. At Mumbai, there are two runways, but they cross each other in an X shape. There are also limitations of taxiways, but, I will not go into such a high level of detail.

Bottom line, the capacity of Mumbai airport is 30 landings per hour, but with a little juggling and using the crossing runway, the Mumbai Air Traffic Control (ATC) is able to push the number up to 36 per hour. But the demand is even higher.

It's a similar situation with Delhi airport, which inaugurated a new third runway, plagued with problems. Drainage, non-functional aeronautical aids, and to top it off, some faceless bureaucrat, probably encouraged by a narcissist politician, allowed a 40 feet (4 storey) tall statue of Lord Shiva along the path of the runway. Now the new runway cannot be used by the Airbus A380, the very aircraft it was specifically built for, till that statue is removed. And we all know, how very impossible that is, in a religiously charged India.

Add to this excess demand and weather. Fog in Delhi, and rains in Mumbai. The system is so over-capacity that it provides the ATC absolutely no room to manoeuvre during bad weather, and flights get even more delayed.

If Mumbai and Delhi are at the top of the list for delayed arrivals, why are they not at the top of the list for delayed departures?

The clock gets reset to the revised departure time, due to the late arrival of the incoming aircraft. The departure time is measured when the airplane doors are closed. Airlines get their passengers on board, close the doors, and then wait for taxi clearance. Due to the traffic jam in the skies, you will find that your aircraft will taxi, and then wait in line, for a long time, to take-off.

Why is Bengaluru International Airport (BIA) at rank 4 in the Top 5 list of most delayed arrivals? Is it not an efficient airport?

BIA is an efficient airport, no doubt. I suspect three reasons. One is thrust on to BIA, one is temporary, and one needs to be addressed.

One, and this is the biggest reason, as the airport spokesperson said, Bangalore's dependence on trunk routes. i.e. Bangalore-Mumbai, Bangalore-Delhi, and more especially after the increase in fares, which dropped the bottom out of regional flights. Flights from Mumbai and Delhi, may leave their gate/stand on time, but get delayed in take-off. So the blame lands up on Bangalore's door-step for the late arrival. It is unfair.

Two, last year, when the new airport opened, there was massive disruption for about a month. I suspect this brought down the overall performance of Bangalore. On the positive side, everyone at BIA have been working very hard, and the kinks have been solved. I suspect Bangalore will be off the list in 2009.

Third, and I have highlighted it in my original post, is weather. Bangalore suffers from fog, between 15th November to 15th February, typically between 3AM and 8:30AM. 6AM to 10AM is peak period, and the fog impacts the performance of arriving and departing aircraft. While fog is limited to a short period in the year, the disruptions are significant enough, to lower the overall annual performance.

The Instrument Landing System at BIA, has been installed incorrectly. Despite being CAT-II capable, which will permit operations in poorer visibility conditions, the equipment is forced to function at CAT-I level. (For a better understanding of CAT levels please read this Wikipedia article).

How, the Airports Authority of India (AAI), which is responsible for the equipment, and has installed over a hundred ILS systems, managed this blunder, is beyond me. Repairs of the installation were to have been carried out during the first six months of operations, i.e. by end November 2008, but given the delays this winter season, they obviously have not.

What is the solution?

We all want to fly during the peak hours of 6AM and 10AM and 5PM and 7PM.

While domestic traffic has declined, the demand during peak hours is sharper. Now that the economy is in the tank, we want to reduce our costs and try and complete all our work in a day trip, or at least not waste the working hours, flying.

Mumbai and Delhi are still way too overloaded, especially during the peak period.

With overall reduction in air traffic and shrinking incomes, there is pressure from the private airport operators MIAL and DIAL, on the ATC to accommodate more flights, as they scramble to earn more income. I cannot fault them. They are in business for profit, not charity, but this adds to the problem.

This economic connection, is the single path to solutions.

The first part of the solution lies with the Directorate General for Civil Aviation (DGCA). It is time they woke up from their slumber, audit the airports, and allocate the maximum number of flights per hour. Any airport scheduling more flights than capacity pays a hefty fine, and is open to punitive law suits from delayed passengers for permitting flights greater than capacity.

To help the airports demand the needed reductions from the airlines, the second part of the solution lies in changing the system of flight slot allocations. India follows a system of "historic rights", i.e. once an airline gets a slot, then they continue to get that slot, till such time they revoke it. Which no airline ever does. Move to system of performance based allocation :
  • If a flight gets delayed, they loose their place in the queue. Similar to an appointment at the doctor, wait for the next appointment to open up, rather than delaying everyone in the queue behind you.
  • Mr. Airline you want a premium landing or take-off slot, pay a premium for it. Hey, but that is unfair to the low cost airlines ? Sorry, but life is not fair.
The airlines can recover the premiums they pay for the slot, from the passengers as a higher fare. They used to charge Rs. 150 ~ Rs. 300 "congestion surcharge", in any case. We passengers who are flying during peak hours, are already paying for them benefit.

Third, and this is partly under way, optimise the air traffic control system. Implement Gagan and the GBAS systems fast. Encourage airlines to use Performance Based Navigation (PBN), and reward those who do.

In the mean time, force the air traffic controllers and pilots to perform efficiently. Right now, the system calls for a two minute separation or 5 nautical miles (10km). World over airports function with a 90 second separation, some even at 60 seconds. A 25 per cent reduction in separation from 120 seconds to 90 seconds at the major airports, will result in a 50 per cent increase in capacity from 30 movements to 45 movements.

Pilots don't react fast enough in the sky, SPIN 'EM. They can land nice and easy sometime before the day is out. Foreign pilots cannot speak English fluently, DE-CERTIFY 'EM. They can fly in less congestion countries. Controllers cannot cope, TRANSFER 'EM. Let them go to nice and easy Jabalpur, Guwahati, or one of the smaller airports in India.

We risk a future similar to La Guardia airport, where the US Department of Transportation is forcing slot reductions, since the system cannot cope any more.

It is time for some radical solutions to this creaking system.
Read more »

Air travel control systems modernised at major airports

According to a PIB release, at a recent parliamentary session of the Rajya Sabha, Minister for Civil Aviation, Praful Patel informed that major work in modernisation of Air Traffic Control System (ATCs) has been undertaken at Delhi, Mumbai, Chennai, Kolkata, Hyderabad, Trivandrum, Mangalore, Bangalore, Nagpur, Ahmedabad, Varanasi and Guwahati.

The expenditure incurred by Airports Authority of India (AAI) on the modernisation of the Communication, Navigation and Surveillance and Air Traffic Management systems (CNS / ATM) during the last three years is as follows: (Rs. 5 Cr. = 1 Million)
  • for the year 2005-06, Rs 118.20 crores;
  • for the year 2006-07, Rs 66.15 crores;
  • for the year 2007-08, Rs 200.71 crores.
After the installation of modern navigational/landing aids, increase in the handling capacity of airspace and airport, enhanced safety, reduction in delays in flight, saving of fuel and thus minimisation of adverse affect on environment, have been observed. Other benefits accrued include uninterrupted operation of flights through airports during the periods of poor visibility, monitoring of aircraft movements in avoiding over-flying over the restricted and prohibited areas and more effective and efficient monitoring of runways during periods of poor visibility.

Patel informed that Monopulse Secondary Surveillance Radars (MSSRs) have been installed at Delhi, Mumbai, Chennai, Kolkata, Trivandrum, Guwahati, Nagpur, Mangalore, Ahmedabad, Bangalore, Hyderabad, Behrampur and Varanasi, by the AAI, at a cost of Rs 229 crore.

MSSR provides position, distance, call sign and altitude of the aircraft and data link between controller and pilot. It also provides seamless surveillance over territorial airspace by filling the radar coverage gaps for smooth and efficient air-traffic flow.

New Delhi, and Mumbai will be installing a GBAS navigation system similar to the one proposed at Newark Liberty airport, by 2010.
Read more »

Newark airport to test Satellite Navigation to reduce delays

Next Generation Ground Based Augmentation System (GBAS) to use global positioning data to pinpoint aircraft positions, rather than Old Generation radar

Newark Liberty International Airport will become the nation’s first major hub to test a new satellite navigation technology to help reduce flight delays, under an agreement approved today by the Port Authority’s board of commissioners.

The technology, called Ground Based Augmentation System (GBAS), will help reduce air-traffic control congestion at Newark Liberty by increasing navigational precision compared with traditional radar-based systems; i.e. planes using GBAS will be able to fly closer together and land more efficiently, without reducing safety.

Such a program will benefit Newark Liberty, which has been plagued for years by congestion and has consistently ranked near the bottom of the nation’s busiest airports in terms of on-time arrivals.

The Port Authority has authorized an estimated $2.5 million to cover the costs and oversee a contract with Honeywell to buy, install and maintain the GBAS system. Honeywell is the only FAA-certified provider of the system.

Continental will invest approximately $1.1 million to outfit 15 planes with GBAS equipment and train pilots to use the system. The FAA has committed as much as $2.5 million to assess the technology and expand its use.

Port Authority Aviation Director William DeCota said
"Satellite navigation has tremendous accuracy and integrity for civil navigation, creating far more efficiency than radar in processing planes and they do not have the obstruction issues that radio waves [used by radar] have,"

"Right now full implementation of satellite navigation in the U.S. and elsewhere to meet future demands and avoid gridlock in the sky is a number of years away and dependent on the expenditure of billions of dollars by the FAA for technologies that will serve as its backbone,"
GBAS, however, is ready to be tested now. The system utilizes a series of antennas and receivers set around the airport’s grounds and a VHF “datalink” to navigational satellites, which communicate together on aircraft position. Sensors are used to bolster the accuracy, availability and reliability of the satellite signals. The technology is particularly beneficial in low visibility landing conditions.

India is already underway, implementing a similar, but Satellite based, system called GAGAN (GPS Aided Geo Augmented Navigation), which is due for completion in May 2011.
Read more »

Government approves GAGAN project to provide seamless navigation over India

The Centre for Asia Pacific Aviation reports that the Government of India has approved the Airports Authority of India (AAI) and Indian Space Reseach Organisation's (ISRO) proposal for the implementation of the GPS Aided Geo Augmented Navigation (GAGAN) project for seamless navigation over Indian airspace at an estimated cost of INR 7.74 Billion.

Ex-post facto approval has also been given to the amount of INR 1.48 Billion already spent in the first phase of the project. With GAGAN, India will be only the fourth country in the world to have a satellite based navigation system.

The management of airspace, a sovereign function, has been assigned to the AAI. The AAI presently uses ground based terrestrial navigation system for providing safe navigation over the Indian airspace. The ground based system has site limitations and range problems.

To overcome the limitations of ground based navigation systems, in 1993, the International Civil Aviation Organisation (ICAO) endorsed use of a Global Satellite Navigation System as a future Air Navigation System for Aviation. Following this, the AAI and ISRO entered into an MoU in 2001 for the implementation of the GAGAN project for seamless navigation over Indian airspace.

The United States has put in place a Global Positioning System (GPS) using 29 satellites at an altitude of 20,000 km orbit. However, the position accuracies required for precision approach and landing, for Civil Aviation, cannot be met by the core GPS constellation, due to the uncertainties in the position accuracies caused by Ionospheric delays, satellite ephemeris and clock errors. The constellation needs to be augmented to provide higher accuracy, reliability and integrity, with the help of a Space Based Augmentation System (SBAS).

In order to provide enhanced accuracies with integrity, reliability and continuity, it is essential to have an augmentation system capable of collecting data in two frequencies over the service area, separate these errors at the master control centre and communicate and correct message to the aviation user in the frequency as that of the core GPS.

To achieve this, an SBAS consisting of a geo-stationary space segment for the core constellation, a ground segment consisting of reference stations, the master control centre and an uplink earth station are required. The reference stations collect dual frequency data, which is communicated to the master control centre. At the master control centre, the errors are separated and the corrected navigation message is sent to the navigation transponder on board the geo stationary satellite, which translates it to the user GPS civil frequency. The GAGAN system proposes to augment the GPS data with the help of a geo stationary satellite to be launched by ISRO and the ground based infrastructure of reference stations, uplink earth stations and master control center created by the AAI.

The implementation of the GAGAN programme is being realized in two phases:
  • GAGAN TDS phase (Technology Demonstration System) - to develop and demonstrate the technological capability. This phase was successfully tested and completed in August 2007.
  • GAGAN FOP (Final Operation Phase) – to be implemented for operational use and to be certified by DGCA. This phase is expected to be completed by May 2011.
INR 1.48 Billion has already been spent in the TDS phase and the balance INR 6.26 Billion is to be spent in the FOP phase. Of this, the AAI contribution is expected to INR 5.96 Billion, from its internal resources, and ISRO’s contribution will be INR 1.78 Billion, from ISRO budget. The AAI has already spent INR 1 Billion and ISRO INR 480 million in the TDS phase.
Read more »