As per preliminary probe reports the radar appeared to have malfunctioned. This had led to problems in the twin-engine helicopter in landing at Kuchai in Saraikela-Kharsawan district, about 100 km from Ranchi.
Sources said after the Agusta AW 109 chopper failed to land at Kuchai, it went back to Ranchi's Birsa Munda Airport but again failed to land.
This led the pilots to "force it down", leading to the crash-landing at 1230 hours, they said, adding that the chopper turned turtle on hitting the ground causing injuries to Munda and others.
Aviation regulator Directorate General of Civil Aviation has already begun to probe the helicopter accident with its Assistant Director (air safety) Sanit Kumar as the investigating officer, Director General of Civil Aviation E K Bharat Bhushan had earlier told PTI.
All aspects of the accident, including the reported technical snag, are being investigated by the DGCA probe panel, official sources said.