KATHMANDU: A recent maintenance-related incident involving an Airbus 320 aircraft of the Nepal Airlines Corporation has once again exposed the gross negligence in NAC’s maintenance practices and shoddy safety culture even when it comes to the upkeep of the state-of-the-art aircraft. An engineer, licensed by Civil Aviation Authority of Nepal, by his actions, had wilfully imperilled the safety of passengers of future flights. According to a highly placed source at the NAC,  instead of pushing the auxiliary power unit button on the overhead panel of the aircraft, KB Thapa, who is also the former director of the NAC’s Engineering Department ‘mistakenly’ engaged the oxygen mask deployment switch while conducting the regular maintenance checks on A-320 Sagarmatha aircraft on January 29. The action resulted in the unintended deployment of oxygen masks in the cabin, the source added. It has also been revealed that engineer Thapa had then attempted to hastily stow away the deployed oxygen masks in their receptacles in an act of cover-up and deliberately withheld reporting the details in the aircraft maintenance logbook, as required by civil aviation regulations. The oxygen masks are safety equipment meant to provide emergency oxygen supply to the cabin occupants if the aircraft witnesses an onboard fire or de-pressurisation. Airbus-authorised procedures have to be followed in the proper stowing of the oxygen masks if deployed. The flight crew of the aircraft which flew to New Delhi the same evening noticed the release of oxygen masks during its return leg to Kathmandu. The captain then had reported the NAC authorities about the incident. “Another engineer who tried to manually deploy the masks from the aircraft after its arrival at the TIA again failed to release over 15 masks,” the source added. When contacted by this daily, engineer Thapa also admitted that he committed a ‘minor’ mistake. He also said that following the Sunday incident, the NAC’s Quality Assurance and Flight Safety Department issued a circular to all concerned for properly reporting such incidents in the coming days.