Ajit Pawar death: AAIB seeks ‘special support’ to retrieve CVR data of Learjet 45 jet

THe Aircraft stroke investigating Bureau (AAIB) on tues said it is conducting a “ elaborated” investigating and has sought “special support” to retrieve data from the cockpit voice recorder (CVR) of the Learjet 45 jet that crashed in Baramati on January 28, killing five people, including Maharashtra deputy chief minister Ajit Pawar.In the Learjet 45, the black box is located near the tail section of the aircraft.In what was its second attempt to land, the jet that was owned by Delhi-based VSR Aviation, went down in flames at 8.44am. According to the civil aviation ministry, air traffic control observed flames near the threshold of runway 11 as the wreckage fell to the left of the table-top tarmac.In a statement issued on Tuesday, the AAIB said, “The AAIB is carrying out a detailed investigation into the accident involving Learjet 45 aircraft VT-SSK, strictly in accordance with the Aircraft (Investigation of Accidents and Incidents) Rules, 2017 and the international standards and recommended practices of ICAO Annex 13.”It said the aircraft was equipped with two independent flight recorders. “Both recorders were exposed to intense heat for a prolonged period during the accident and sustained fire damage,” the agency said.The bureau stated that the Digital Flight Data Recorder (DFDR), manufactured by L3-Communications, has been successfully downloaded at the AAIB Flight Recorder Laboratory.However, it said the Cockpit Voice Recorder (CVR), manufactured by Honeywell, is undergoing detailed technical examination. “Assistance has been sought from the accredited representative of the state of manufacture for specialised support in data retrieval,” it said.A black box is usually orange in colour and records critical flight parameters and cockpit conversations and is central to reconstructing the sequence of events leading to an accident. The devices that record flight data and cockpit audio are housed in reinforced casings designed to withstand extreme impact and intense fire.This comes a day after HT had on Monday reported that the black box was understood to have suffered extensive damage and that the possibility of it being sent abroad could not be ruled out.“The AAIB is diligently following all prescribed technical and procedural protocols to ensure a comprehensive, objective and evidence-based investigation. The Bureau remains fully committed to transparency and will share further information at the appropriate stage of the investigation,” the statement said.Explaining about black box units and its importance in a crash, an industry expert said, “Earlier, most aircraft had independent Cockpit Voice Recorders (CVR) and Digital Flight Data Recorders (DFDR), often supplied by different manufacturers. Integration of both into a single unit is a relatively newer development seen in some aircraft types. Even today, many aircraft continue to operate with separate systems, which seems so in the crashed jet too.”“As far as data retrieval is concerned, manufacturers such as Honeywell have highly sophisticated equipment to extract information, even from recorders that have sustained fire damage. These devices are designed to withstand extreme impact and fire, but prolonged exposure to intense heat can sometimes affect them,” he added.Another expert requesting anonymity said, “If the investigating authority is unable to fully extract the data in India, or considers it technically risky, the original equipment manufacturer (OEM) may be involved. This could mean sending a technical team to assist at the investigation lab under supervision, or, in some cases, taking the recorder to the manufacturer’s facility abroad where more advanced tools are available. In either case, the process remains under the supervision of the investigating authority.”“The solid-state DFDR is designed to withstand severe impact, fire, crash forces and even partial destruction. In most cases, the data remains intact and maintains its integrity. The DFDR records 88 separate parameters, which are typically sufficient to help pinpoint the exact cause of a crash. It is crucial to establish the facts of the accident and incorporate necessary safety systems and measures to make VIP travel safer,” Mark D Martin, founder of Martin Consultancy said.