Biman Bangladesh Airlines Limited

AD 2011-02-07 asks for repetitive vibration survey at 350 cycle interval. To us this requirement is very much harsh for operators like Biman Bangladesh Airlines Limited. Because 1. Biman continuously monitors engine vibration level by using Airborne Vibration Monitoring system. Most of the accidents/incidents that caused AD 2011-02-07 to be issued were occurred on aircrafts that has no Airborne Vibration Monitoring system. 2. Biman performs Engine Condition Trend Monitoring by using SAGE program. Biman constantly monitors engine core and fan vibration, fuel flow, EGT, N2, oil temperature and oil pressure. 3. Besides repetitive vibration survey using external equipment is not economic for Biman. Because Biman has to take loan the equipment every time at high price. And purchasing such equipment for old DC10-30 fleet will be a great financial border. In this circumstance, Biman’s proposes to waive the requirement for repetitive vibration surrey for operators who has Airborne Vibration Monitoring system and performs Engine Condition Trend Monitoring.