NATIONAL 2 -[GORKHA PENSIONS (Spotlight Weekly)]

Ready, Get Set

Civil Aviation authority needs to do a lot of homework before it is actually able to utilize the RADAR facility

By A CORRESPONDENT

Some two years back officials responsible for air safety toasted cheers with a reason. More than four decades after civil aviation began in Nepalese skies, the only international airport (Tribhuvan International Airport) finally had Aerodrome and Secondary Surveillance Radar installed in its neighborhood.

Situated nearby TIA, at Sanothimi, Bhaktapur, the project --named TIA Modernization Project RADAR Installation -- began in July 28, 1994 with the objective of installing terminal Radar System at TIA for air safety in and around the international airport.

Having completed the constructional works of the buildings and the necessary equipment installation, the TIA established a separate "approach control" unit to guide inbound and outbound air traffic. The unit was first lumped together with "area control" and "aerodrome control" services -- all three services were provided by the control tower alone in the past.

Installed under the Japanese grant assistance of 1.7 billion Rupees, the RADAR facility was handed over to the government in 1998.

Then, little did the Civil Aviation Authority of Nepal know that much remained to be done before the RADAR could be made fully functional.

One hitch obstructing the smooth function of RADAR has been the state of the aircraft operated by private companies. Aviation experts claim that many private aircraft do not have a device called transponder that reads the signals emitted by RADAR and replies them.

Which means Air Traffic Controllers at the TIA can only see the aircraft on their RADAR scobe but cannot communicate with the pilots flying the aircraft.

Supposing that an aircraft is flying quite low and is in danger to collide against a mountain, the RADAR system is supposed to locate the altitude of the aircraft and make the pilot aware of his position so that he could avert the possible accident.

But when the said aircraft does not have a transponder, its pilot cannot communicate to the Air Traffic Controllers. "So many private airlines are yet to install the transponder in the aircraft," say tourism experts. "And as long as that does not happen the RADAR cannot enhance the safety of such aircraft."

And there is yet another reason why the ASR/SSR RADAR has not been able to function smoothly. Though the installed ASR/SSR RADAR has the range of 60 to 200 nautical miles -- meaning it can locate an aircraft flying in the sky of the Indian city of Varanasi -- at present the system cannot locate aircraft flying outside the valley and below the altitude of the mountains surrounding it.

Reason? The signals emitted by the RADAR gets obstructed by the surrounding mountains and thus do not reach the aircraft flying out side the valley.

Which means, most of the domestic aircraft cannot be located by the RADAR while they are out of the mountain rim around the valley. These mountains are on average 9000 feet high while aircraft in domestic route fly as low as 6,000 feet.

"Therefore, there are difficulties for the RADAR to guide in and out the aircraft from the valley," says Pradip Nath Sharma, Chief of TIA Modernization Project.

Does that mean, the TIA will always have to be a risky airport? No, if only there is a back-up facility for the ASR/SSR RADAR, say experts. They claim if only yet another SSR is installed atop one of the high mountains around Kathmandu, the ASR/SSR RADAR will be able to operate at its maximum capacity.

Mountain Phulchowki has been identified as a feasible site for the installation of the backup RADAR. And the new project will cost around 18 million US Dollars, according to CAAN officials.

Besides the back-up facility, what CAAN needs to do is tighten the screw of private companies and make them install the required equipment in the aircraft so that they could benefit from the RADAR facility.

At a time when Nepal has been witnessing increased number of air crashes and accidents every year, air safety does matter a lot.