New Delhi, Dec 10 (IANS): Air India and US aircraft major Boeing have started to upgrade software and components on the national carriers' fleet of 787 Boeing Dreamliner aircraft, Minister of State for Civil Aviation K.C. Venugopal said Tuesday.

Venugopal informed the Rajya Sabha that a modification package has been prepared by Boeing for Air India's 787 Dreamliner aircraft.

"The modification is being sequentially carried out on each of the Dreamliner aircraft during a 10-day maintenance grounding with effect from Dec 1, 2013," he said.

According to Air India, the Dreamliners would be modified on a one-by-one basis and that the majority of the fleet will be in service.

Earlier, aircraft maker Boeing said its technologically advanced 787 is a safe aircraft and the company is keeping a watch over every problem faced by the plane.

The reliability issue on 787s has been in the news following incidents like a large belly panel of an Air India's 787 falling off as the plane landed at Bangalore airport on October 12.

Currently, aviation regulator Directorate General of Civil Aviation (DGCA) along with Air India and Boeing have been probing the incident.

As Boeing's most modern aircraft has been facing many problems, in January 2013 the DGCA grounded all Air India's 787 aircraft after a US Federal Aviation Administration directive to stop operations of all such planes delivered so far to various airlines.

After nearly four months and modification to the aircraft's batteries, the DGCA allowed the plane to be operated again.

Air India booked 27 Boeing 787s in a mega-deal in 2006. It currently has 10 planes. All the aircraft are expected to be delivered by 2016.

The deliveries of the aircraft were delayed due to certain design and production issues. The aircraft were scheduled to be delivered from September 2008 to October 2011.