The state's top bureaucrat said the Cockpit Voice Recorder (CVR) or 'black box' recovered from the wreckage was yet to be decoded. 'Some media reports that the pilots spoke to the ATC staff in Hindi are baseless because the material in black box is yet to be decoded,' he said.

He said the necessary checking of the chopper was done before flying. 'Pilots also spoke to the meteorological office. The pilots had undergone medical checkups before flying. The anti-sabotage checking was also done. It all took 20 minutes and the chief minister spent the time going through some files,' he said.

Reddy said Bell 430 was one of the best helicopters and there was no room for any doubts on its airworthiness. He said the government would not stop using such helicopters. 'Some helicopters of the Indian Air Force also crashed but the air force did not stop using them,' he said.

YSR, as the late chief minister was popularly known, his special secretary, chief security officer and two pilots were killed Sep 2, an hour after he took off from Hyderabad for Chittoor district to launch a mass contact programme.

The helicopter crashed in bad weather minutes after it lost contact with ATC around 9.12 a.m. The charred bodies of the victims with the wreckage found 24 hours later after one of the biggest searches in India's aviation history involving IAF helicopters, fighter aircrafts like Sukhois and special aircraft of the Indian Space Research Organisation (ISRO).