Airport operator Delhi International Airport Limited (DIAL) on Tuesday said in a statement that investigations carried out by the four-member committee are still on and the committee has sought time till October 15 to complete its report and suggest remedial measures.

Sources within the inquiry committee have said the extension has been sought because DIAL is yet to provide a detailed report on the structure and design of T1D and the kind of material used in construction.

Initial investigations, however, have revealed the roof had structural faults, sources said.

A day before the deluge, the bolts on the roof had been unscrewed for some repair work and were not fixed properly. This made it easy for the winds to blow away a few panels of the roof, sources said.

On August 21, flight operations at IGI Airport had to be shut for nearly two hours after a heavy downpour for nearly 30 minutes. There was flooding in the new terminal 1D because the ceiling leaked at several places and a part of the roof near Gate 14 had crashed.

On August 22, DIAL had set up a four-member committee to look into the matter. The committee was also expected to suggest remedial action and submit its report in four weeks.

The committee comprised of RSSLN Bhaskarudu, Independent Director (DIAL); P Seth, nominee of the Airports Authority of India; P S Nair, CEO (DIAL) and Prof (Dr) Meher Prasad, Structural Engineering Expert from IIT Chennai.

The expert committee is also being assisted in its investigations by Hafeez Contractor (Architect), M/s BL Kashyap & Sons (construction contractor), M/s Tata Blue Scope (roofing contractors) and M/s Tata Consulting Engineers (Project Managers).

In the aftermath of the incident, Hafeez Contractor had said the building’s roof was not designed to take such a heavy winds, “which were almost tornado-like for 15 minutes” on August 21. “We need to rework the roof design now for a higher wind load,” Contractor had said.

“Investigations so far have revealed that the roof had structural flaws,” the source said.