The plane, with 3 crew members and 7 passengers, including the two senior Congress leaders, had taken off from Bangalore and was headed towards Delhi when the air pressure inside the cabin started to drop, forcing the pilot to make an emergency landing in Bhopal, according to the final investigation report by the Directorate General of Civil Aviation (DGCA).
The Falcon 2000 VT-HGL jet, manufactured by Dassault Aviation in 2006, was owned by Ashok Leyland and operated by Ashley Aviation.
In technical terms, it was the faulty pneumatic and electro-pneumatic outflow valve that led to the reduction in cabin pressure below required levels.
“M/s Ashley Aviation, Falcon 2000 aircraft VT-HGL, while operating a non-scheduled passenger flight from Bangalore (HAL) to Delhi, was involved in an emergency landing at Bhopal on 18.07.2023 due to pressurisation failure,” the DGCA report stated.
There were no injuries to any of the crew members or passengers on board the aircraft. All of them were found in good health, the report mentioned.
What causes pressurisation failure
Air pressure inside the aircraft decreases when the aircraft climbs to 10,000 feet above ground. To maintain the pressure, an air conditioning system pumps air inside the cabin to enable normal breathing for the occupants.
This air comes from the pneumatic system that sends pressurised and heated air into the aircraft as the outside temperature is at least minus 40 degrees Celsius. The system also releases air outside the cabin through the outflow valve to regulate cabin pressure and ensure normal breathing. Any leakage in the outflow valve can destabilise and reduce the cabin pressure, which is what happened in the July 2023 incident.
“Post-incident, both pneumatic and electro-pneumatic outflow valves were suspected to be faulty and were sent to M/s Dassault Aviation, France, for shop examination. The shop report confirmed that the valves were contaminated and a leak was found, making them out of order,” the DGCA report stated.
Not the first time
This particular aircraft, which was carrying Sonia Gandhi and Rahul Gandhi on board, has had a history of pneumatic outflow valve malfunctions. However, the DGCA report notes that only one incident (July 18, 2023) was a repetitive snag, as all others recurred after 50 hours of earlier occurrences.
In previous instances, the jet’s air pressure outflow valves were found faulty and replaced on March 3, 2023, September 7, 2022, September 30, 2019, and December 17, 2018.
Ashley Aviation had been instructed to carry out preventive maintenance to test the cabin pressure every 12 months or after 800 hours of flying.
(Edited by : Anand Singha)
First Published: Nov 18, 2024 5:28 PM IST
