Eleven long years have elapsed, but the instrument landing system (ILS) is yet to be upgraded to the category-2 at three international airports in Bangladesh, insiders said.
The reluctance of the Civil Aviation Authority of Bangladesh (CAAB) has thus caused financial losses to the airlines and also adding to passengers' sufferings.
Industry insiders said the CAAB made a move to install backup power supply systems at the airports in 2007.
Domestic operators have repeatedly called for implementing the low-cost project aimed at enhancing visibility during winter, but to no avail.
They have expressed concerns with the approach of winter that usually lasts four to six months.
As far as the ILS-1 approach is concerned, large airliners of Biman take risks to land at Hazrat Shahjalal, Shah Amanat and Osmani airports because of poor visibility in winter mornings.
In most cases, foreign carriers go back to the Bangkok airport or pilots fly the air craft in the sky for hours, burning tonnes of jet fuel.
Besides, passengers become panic as they cannot land on schedule while the airlines have to provide them with food and necessary services at a different airport.
Talking to the FE, many people in the aviation circles said the CAAB was interested only in big projects.
Upgrading the airports to the ILS-2 category is a low-priority project to them as it involves small funds, they alleged.
The ILS approach is related to safety. The Sylhet and Chattogram airports even do not have the capacity to handle disrupted flights.
The CAAB spends on so many unproductive projects like 150 staff quarters at the Osmani airport, walkway around it and other unnecessary components.
But surprisingly, no person is available at the control tower when necessary.
For ILS-1, aviation experts said, an aircraft requires 2,000-2,800 metres of visibility to land which is quite difficult during foggy weather.
If the airports are upgraded to the ILS-2, visibility can be 600-1,200 metres, which is quite comfortable for the pilots, they mentioned.
The experts said the airports have approach light, runway light and approach aid for both aircraft and ground handling operators for safe landing during winter.
But there is no backup power supply that will be active within a fraction of a second. This small piece of work has been remaining pending with the CAAB year after year, they observed.
Three things are necessary for ILS-2 to enhance visibility during foggy weather -- main power supply, backup generator and instant power supply (IPS) to be active within a fraction of a second.
But any IPS is yet to be installed at the airports.
During winter, airport sources said, flights get disrupted due to fog. Flights start landing one after another from 11:00am to 1:00pm, creating chaos at the airports.
Even 16 aircraft land during the time, making it tough to handle them with six boarding bridges and eight arrival luggage belts.
About 26 foreign aircraft and four domestic carriers, including Biman and many unscheduled chartered planes, land at the Hazrat Shahjalal Airport daily.
When asked, Biman Bangladesh Airlines general manager Shakil Meraj said the most important thing for an aircraft is safe landing and take-off.
The airports needed the ILS-2 approach for safe landing, he told the FE.
"CAAB must enhance its capacity to implement various necessary projects considering the growth of the country's aviation sector," he said.
NOVOAIR managing director Mofizur Rahman said, "The operating costs of the airlines increase as well as passenger sufferings due to the ILS-1 approach at the major airports."
"Everything is there to upgrade the airports. It only needs some initiatives by CAAB," he added.
Experts said a Boeing-777 burns 15 tonnes of fuel in one hour while it is six tonnes for a Boeing-737.
The problem of holding an aircraft in the sky for one and a half hours to two hours sometimes makes Biman pilots land taking risk instead of burning fuel.
But pilots of foreign carriers, especially the Middle-Eastern ones, do not take risks and land at nearby airports like Bangkok avoiding Kolkata.
Dismissing allegations of operators and experts, CAAB member (operations and planning) Air Cdre M Mostafizur Rahman said the percentage of aircraft which cannot land due to fog is very insignificant.
Besides, millions of flights are cancelled due to snowfall globally, meaning there is no control over the weather, he added.
About passenger sufferings and schedule disruptions, Mr Rahman said if the airports can handle the present situation, there is no problem.
"We can't upgrade the Dhaka airport overnight. Every airport lacks capacity. The situation will continue until construction of the third terminal," he said.
Mr Rahman, however, said the process of upgrading the airport to the category-2 is underway.
A team working on it submitted the final study report regarding the project, he uttered.
A plan of action would be prepared soon, he added.
The CAAB member outright denied the allegations of delays in implementing multiple projects.
He said CAAB implements every project following due procedure and rules of the government which may take time.
But experts said the issues of passenger infrastructure and operational infrastructure is totally different.
The CAAB had no authority to delay a project for 11 years, they noted.
