AN-32 was flying from Chennai to Port Blair when it went missing. The aircraft has 29 people on board.

Highlights The aircraft went missing on July 22nd after it took off from Chennai.

Officials say plane may have plunged from an altitude of 23,000 feet.

The last call from the aircraft was around 16 minutes after take-off.

Union defence minister Manohar Parrikar on Friday told parliament that India has sought help from US to check if their satellites captured any signals from the missing AN-32 aircraft , while noting there was very little possibility that sabotage played any role.Giving clarifications on the missing aircraft in the Rajya Sabha, the minister said he was "disturbed" at the aircraft's sudden disappearance, and even experts are "puzzled"."I am also disturbed at such a sudden disappearance. I spoke with many air chiefs, other senior air force personnel, they also are puzzled by the sudden disappearance," he said.Assuring the house that the aircraft had "adequate lifetime", Mr Parrikar also said that maximum efforts are being made to reduce accidents and also that any aircraft not fit for flying was not flown.He said that this aircraft "was almost at the end of the range of passive radar. In effect in another 10 minute it would have crossed the limit of the passive radar and there is an area around 150-200 nautical miles where there is no radar coverage either from Chennai or Port Blair ."He also said that the aircraft had undergone its first overhaul, and had already flown for 179 hours after that. The pilot had flown for over 500 hours on the route."So it is not that something new was happened," he said."Only thing which was recorded was because of a cumulonimbus cloud which normally no aviator will like to enter into because it is a very charged and heavy cloud... they (pilots) said we are deviating to right," Mr Parrikar said, adding that this happened 7-8 minutes before the plane went off radar."At the time of coming down it actually tilted to the left and descended very fast from 23,000 feet in few seconds. Then it disappeared from the radar."Two things happened, it was at the age of radar signal where you don't get very active radar signal, you just keep track of it. There is no SOS, no transmission at any frequency, it just disappeared... That is the worrying part," he said.He also said that no signal from the emergency beacon locator has been tracked, but added that that it was "difficult that it will be actually activated" if the aircraft dives inside water."In the earlier Coast Guard case (Dornier crash) also, it had not activated," he said.The defence minister also said there was very little chance of a sabotage."I can't speculate... we are searching for it but I can say only this much, though we are checking all angles, the possibility of a sabotage is comparatively very less."They have standard operating procedure, all passengers were from defence forces."About search operations, he said US has been contacted for any information from their satellites."We did not get even a single signal. We are now contacting US, if their satellites have picked signals," he said, but added that a satellite may not have picked signals because of thick cloud cover, and it also depends on whether a satellite was crossing the area at the time.He added that so far, 505 hours of air sorties have been undertake and 23 different items were noticed.Of the 23 inputs, there were 17 visual sightings and six transmissions.Indian survey ships are searching the seabed, and submarine Sindhudhwaj, which had finally located the crashed Dornier, is carrying out an underwater search."Round the clock air surveillance is being maintained. There are 10 Navy ships in the area. The depth of water is 3,300 to 4,000 meters. Special vessels have also been summoned," he said.The minister added that he was personally monitoring the whole operation, and he was getting updates every few hours.