As many as 176 planes operated by non-scheduled and general aviation operators do not have flight data or cockpit voice recorders, the government told the Rajya Sabha on Monday. Under the norms, aircraft that have a take-off weight of less than 5,700 kilograms are required to mandatorily have CVRs only if they had received an airworthiness certificate on or after January 1, 2016. In a written reply, Minister of State for Civil Aviation Murlidhar Mohol said that a total 2,263 aircraft were registered and issued certificates of airworthiness (C of A) before January 1, 2016. "Aircraft operated by Non-Scheduled Operator's Permit (NSOP's) /General Aviation (GA) operators which are not equipped with Flight Data Recorder (FDR)/ Cockpit Voice Recorder (CVR) are 176," Mohol said. His reply was to a query on whether the government has data on the number of aircrafts without cockpit voice and flight data recorders. The nearly 40-year-old Beechcraft C90A aircraft that crashed in Jharkhand las