Cause of Aarey chopper crash not known: report

Clutch failure had forced pilots to attempt landing in 2016

An investigation into a helicopter crash during an emergency landing near Royal Palms in Aarey that claimed three lives in December 2016, has not been able to conclude what caused the clutch failure that forced the pilots to attempt landing, during which it fell to its right, leading to a fire and casualties.

The report, submitted by the Aircraft Accident Investigation Board (AAIB) to the Union Ministry of Civil Aviation in December 2017, was only made public over the weekend. The 1992-make helicopter, belonging to city-based Aman Avation and Aerospace Solutions was a Robinson R44 Astro model originally owned by Pawan Hans. It operated out of Juhu and was used for joy rides.

Second joy ride

On the day of the accident, the helicopter was on its second joy ride of the morning. The first sortie was uneventful. As per the 45-page investigation report, the pilot contacted the Juhu Air Traffic Control (ATC) when it was over Powai. As per the technician who was on board the helicopter, the passengers were shown Powai lake, Vihar Lake and Film City before turning to return to for Juhu Airport.

Lone survivor

The technician, the lone survivor, was looking outside the cockpit when he felt some reduction in the Revolutions Per Minute, the report said. This forced him to immediately look inside the cockpit but he did not observe any of the caution or warning lights glowing.

Simultaneously, while at an altitude of approximately 500 feet above ground level, the pilot informed the ATC that he was making a forced landing in Powai due clutch failure. As per the tape transcript, the pilot in his communication to the ATC said, “Forced landing in Powai, Clutch in is failure”.

The technician further said the pilot tried to land on level ground, but saw some children playing there and decided to land beside the ground. However, during this process, the helicopter kept losing height and hit a bunch of trees ahead of the field. The helicopter finally impacted the ground between the bunch of trees, and caught fire soon after.

Local people took the technician to the left out of the helicopter. The pilot and the two passengers rescued by local people had received serious injuries. The police arrived at the site after receiving a message from the local people, and all four persons were admitted to the nearby hospital. The pilot was declared dead at hospital, and the passengers, also critical, succumbed to their injuries.

As per the report, the cockpit and its instruments were destroyed. According to the findings, the accident occurred as the helicopter toppled to its right during the final impact with the ground, when the pilot in command was carrying out a forced landing (autorotative landing as required by the Pilots Operating Handbook) due to reported clutch failure. The report said, “The exact cause of the clutch failure could not be established.”

The report also noted that clutch Circuit Breaker located under the co-pilot’s seat and is required to be red collared (though was not done on the subject helicopter) for ease of identification so that the co-pilot be able to pull it out by feel without physically looking at it. This was found to be not pulled out by the pilot probably because it is very difficult for the pilot to do so at low altitude where reaction time is less.