V Ayyappan | TNN
Nov 27, 2009:
Chennai: Less than two months after it was introduced at the Chennai Air Traffic Control, the state-of-the-art Performance Based Navigation System was disabled for 24 hours from Wednesday evening, following the failure of a radar component. This rendered the secondary radar that monitors aircraft movement beyond 60 miles dysfunctional. The PBN system works on predetermined air routes for landing, take-off and mid-air locations for holding aircraft.
The snag delayed several flights from 30 minutes to an hour during peak hours till the radar was restored on Thursday evening. Sources said that Calibrated Performance Maintenance Equipment (CPME), which indicates that the radar is functioning and the data it displays is accurate and reliable, stopped working.
Though blips were seen on the air traffic control screens, there was no way to find out whether the altitude, speed and location of the aircraft displayed were accurate in the absence of CPME. The approach radar used for guiding departures and arrivals worked well.
As the CPME did not revive even after repeated attempts of repair, the AAI airlifted a spare equipment from Mangalore and installed it by around 6.30 pm on Thursday, said an AAI official. Flights were delayed because controllers were not able to effectively monitor air space over Bangalore and Hyderabad airports where a majority of air routes intersect at different levels.
Controllers had to work as if the radar was not available at all. They called up pilots to get their location. “Controllers were not able to provide high level for many aircraft because flights landings and take-offs in Hyderabad and Bangalore often cross air routes from Chennai. These intersecting air routes are located beyond 60 miles from the city and are in the coverage area of the secondary radar,” said a pilot.
The snag at Chennai airport also led to minor delays in other airports as well because requests were relayed to other airports to delay departures to prevent bunching of aircraft. Air traffic controllers could not use areas defined as holding points for aircraft and the feeder routes that were defined for landing and take off at Chennai airport.
Sources said the equipment that failed was more than 10 years old and the airport did not have a standby though all major airports have two CPMEs.
“The airport had two CPMEs sometime ago. But, one stopped working. It was never replaced. The airport was using the remaining one without a standby for so long. If it was replaced, AAI would not have had to scout for spares,” said a source. The AAI is planning to install two state-of-the-art radar and automate air traffic control system by the end of the year. RADAR FAILURES
Both radar have failed thrice in
January, 2009 They failed again in May, 2009 In September, 2009 workers dug up and snapped cables
Radar have failed because of tech snags several times since July 2008
Chennai airport does not have standby radar so aircraft schedules get affected every time a radar fails
AAI is planning to install two radar by the end of the year
No comments:
Post a Comment