No Mayday or distress call from the pilot of the Trans Bharat Aviation helicopter was recorded before it crashed near Sthan Marwari in Uttarakhand on Friday, investigators probing the incident have told The Indian Express. The crash killed the pilot and five passengers.The absence of any distress communication, along with eyewitness accounts and videos showing the helicopter’s descent, raises the possibility that something happened suddenly, leaving the pilot with little time to alert other aircraft, an official familiar with the ongoing investigation told The Indian Express on condition of anonymity.“Some aviation experts suggest there might have been a mid-air collision – a bird or a drone – though we are still figuring it out,” he said.The official added that the manner in which the helicopter fell did not appear consistent with an engine failure.Read | As Uttarakhand chopper crash probe widens, focus on flights that took off before and afterThe Chamoli district administration’s initial Action Taken Report had attributed the incident to adverse weather conditions in the Hathi Parvat area, where the helicopter reportedly crashed while descending towards a lower altitude. The IMD had issued an orange alert for Chamoli on October 30, warning of thunderstorms, lightning, hail and gusty winds of 40-50 kmph in isolated areas.However, the official said, “There was no communication about poor visibility or any issue that this particular pilot faced. Otherwise, some issue would have been raised over the RT (radio telephony).” Wreckage of the helicopter in Chamoli, Uttarakhand, on Friday. (ANI)As The Indian Express had earlier reported, another helicopter took off from Badrinath just eight minutes after the Trans Bharat aircraft. It landed safely at its destination. Yet another helicopter departed nearly an hour later, while two flights that had flown before the crashed aircraft also completed their journeys safely.Story continues below this adThe timing and sequence of these flights are among the aspects being examined as part of the investigation.The official said pilots of other helicopters operating in the area have shared their versions with authorities. None reported receiving a distress call or hearing any communication about poor visibility or other operational difficulties over radio telephony (RT).Read | Helicopter operators threaten to suspend Char Dham services over co-pilot ruleThe Trans Bharat Aviation helicopter had departed from Dehradun at 12.20 pm on Friday and landed at Badrinath at 1.11 pm. After picking up five passengers, it crashed while returning to Dehradun.Flight operations in the Badrinath Valley were suspended between 9 am and noon on Friday due to inclement weather, but resumed after conditions improved.Story continues below this ad SDRF personnel prepare to conduct a rescue operation in Uttarkashi. (Image source: SDRF)Camera behind pilot’s seat being searched forThe official said there was no black box in the single-engine helicopter. Investigators are instead trying to recover a camera usually installed behind the pilot’s seat, which could offer clues about the final moments.“The team is active on the ground trying to find the camera. It’s difficult terrain. It’s getting difficult to find the camera. But yes, our priority is to find it anyhow,” he said.Also Read | Why are so many helicopters crashing in Uttarakhand? The risks explainedThe investigation team is also questioning eyewitnesses who saw the helicopter descending before it crashed and consulting aviation experts. The Aircraft Accident Investigation Bureau (AAIB) is probing the accident.Story continues below this ad“Everything is under investigation. Maybe if we get some more clues, more evidence, we’ll be in a better position to conclude something,” the official said.Charter helicopter services suspended for remainder of seasonMeanwhile, charter helicopter services for the Char Dham Yatra have been suspended for the remainder of this season following a meeting between helicopter operators and the Directorate General of Civil Aviation (DGCA) on Monday.The meeting came after 11 helicopter operators wrote to the authorities opposing the DGCA’s decision to make two pilots mandatory for charter helicopter operations for the remainder of the ongoing pilgrimage season.Story continues below this ad SDRF personnel prepare to conduct a rescue operation in Uttarkashi. (Image source: SDRF)The operators raised concerns that the requirement would make it financially unviable for them to continue operations, particularly with only a week left in this year’s yatra.“They raised a few concerns that this might not be financially viable for them to continue the chopper services. And considering that only one week is left in the Char Dham Yatra for this year, they requested DGCA to re-look at this decision,” CEO of UCADA Prateek Jain told The Indian ExpressHe added that deliberations would continue and a final decision on the twin-pilot requirement would be taken before the commencement of next year’s yatra. “For now, we’ve all agreed to call off the charter services for Char Dham Yatra for this season,” he said.Passengers who had already booked charter services have been informed that they would receive refunds, the official added.Story continues below this adThe DGCA had made a co-pilot mandatory for charter helicopter operations after Friday’s crash. The decision had prompted the 11 operators to raise objections over its financial implications.