The much-hyped Category II Instrumental Landing System (ILS) at Calcutta airport is now awaiting a key software for installation.

?Installation of the Runway Visual Range (RVR) mid-runway is the most important project for us now,? Praveen Seth, regional executive director, eastern region, of the Airports Authority of India (AAI), said on Saturday.

Once installed, pilots will be able to take off and land in low visibility conditions, which will help reduce delays, especially during winter.

?The meteorological department of Calcutta airport is in the process of acquiring the software,? Seth said. He claimed that ILS will be commissioned before winter fogs set in.

The RVR is now set at both ends of the airport. ?In Category II ILS, the RVR will have to be set up mid-runway for better visibility for pilots,? said Rajendra Pal, airport director.

Now, pilots can land at a visibility of 550 m and can decide whether or not to land from a height of just 60 m, but with Category II, it will be reduced to 350 m and 30 m, respectively.

According to officers, a number of jobs had to be completed before RVR installation.

The main runway has been upgraded and Category II lights have been installed at the airport.

?There were several obstructions that had to be removed,? Seth said. Since aircraft can fly lower after Category II ILS installation, there were dangers of collision with some chimneys near the airport.

Some of the chimneys have been removed, while the heights of others were reduced. ?This was the basic restructuring work that had to be done before the final installation,? an officer said.

The Rs 18-crore installation involves setting up bright lights along the ?centre line of the runway?. But, Calcutta airport will do tomorrow what Delhi airport did yesterday.

The Category III-A facility is in place at Indira Gandhi International Airport, allowing pilots to land with a visibility clearance of only 200 m.

Several measures have been taken to spruce up Calcutta airport. Airport director Pal said last year, Rs 45 crore was spent on infrastructure development, highest for the airport since its inception.

The check-in area of the international terminal has been increased from 600 sq m to 1,800 sq m. The number of check-in counters at the terminal has gone up from 19 to 27. At the domestic terminal, too, the check-in area and counters have been increased.