NEW DELHI: Get ready for some massive delays at IGI Airport this winter. The instrument landing system (ILS) on the main runway (28/10) was downgraded from CAT-III to CAT-II a few months ago, meaning that it can now support operations only in visibility up to 350m instead of 50m. On Wednesday, the Airports Authority of India (AAI) attempted re-calibration of ILS but failed and now officials are worried that it may not be possible to rectify the problem during this winter.
This means IGI, with an average aircraft movement of 60-65 per hour, will be left with only one runway to handle flights when visibility dips below 350m. The airport witnesses an average of 85-100 hours of below 350m visibility between December and January. In 2010-11, it saw 105 hours of below 350m visibility between November 18 and March 3.
The new runway, which is CAT-III compliant, is prone to getting fogged much before the other two runways and also usually witnesses zero visibility before the other runways are affected. Both the main and secondary runways can support operations only in CAT-II conditions that is 350m or above. The other major problem will be faced by the low-cost carriers that would have to taxi about 40 minutes to get from terminal 1D to the runway.
"We initially thought that the new cargo complex, which has a metallic facade, was interfering with ILS signals. The airport management Delhi International Airport (P) Ltd (DIAL) undertook a massive exercise to cover the building with plywood but that attempt has failed. It has made little difference to the signals and we were unable to upgrade the main runway to CAT-III. The problem is that with little time left for the fog season to start, we are not even sure what the problem is," said a senior official.
DIAL has even called in the ILS manufacturers but sources reported that they, too, were unable to zero in on the culprit. "Company officials have said it is not the cargo complex that is the problem but again have no idea what is. In that situation how do we even look for a solution? If we are required to change ILS, it will take time and the work cannot be undertaken during the fog months," said a source.
The Met department has said dense fog is expected between December 20 and February 20 but there are chances of a couple of spells of dense fog anytime from end-November. "Visibility has already started falling at the airport and once winter starts, we can expect fog in varying degrees," said R K Jenamani, director in charge, IGI Met.
This means IGI, with an average aircraft movement of 60-65 per hour, will be left with only one runway to handle flights when visibility dips below 350m. The airport witnesses an average of 85-100 hours of below 350m visibility between December and January. In 2010-11, it saw 105 hours of below 350m visibility between November 18 and March 3.
The new runway, which is CAT-III compliant, is prone to getting fogged much before the other two runways and also usually witnesses zero visibility before the other runways are affected. Both the main and secondary runways can support operations only in CAT-II conditions that is 350m or above. The other major problem will be faced by the low-cost carriers that would have to taxi about 40 minutes to get from terminal 1D to the runway.
"We initially thought that the new cargo complex, which has a metallic facade, was interfering with ILS signals. The airport management Delhi International Airport (P) Ltd (DIAL) undertook a massive exercise to cover the building with plywood but that attempt has failed. It has made little difference to the signals and we were unable to upgrade the main runway to CAT-III. The problem is that with little time left for the fog season to start, we are not even sure what the problem is," said a senior official.
DIAL has even called in the ILS manufacturers but sources reported that they, too, were unable to zero in on the culprit. "Company officials have said it is not the cargo complex that is the problem but again have no idea what is. In that situation how do we even look for a solution? If we are required to change ILS, it will take time and the work cannot be undertaken during the fog months," said a source.
The Met department has said dense fog is expected between December 20 and February 20 but there are chances of a couple of spells of dense fog anytime from end-November. "Visibility has already started falling at the airport and once winter starts, we can expect fog in varying degrees," said R K Jenamani, director in charge, IGI Met.
No comments:
Post a Comment