Write 8 pages thesis on the topic air accident investigation branch. On June 10, 1990, a BAC 1-11 aircraft British Airways Flight 5390 left the Birmingham International Airport and headed for Malaga with eighty-one passengers on board, as well as two flight crew and four cabin crew members. On reaching 17,300 feet, the windscreen was blown off, leading to the pilot almost being sucked out of the plane. The officers carrying out the investigation identified the immediate cause of the accident to be the fastening of the replacement windscreen with wrong-sized bolts. Engineering factors were most to blame for the accident of BA flight 5390. First, the wrong bolts were used for the securing of the windscreen, with most of the bolts being of the incorrect diameter. The technical engineers failed to uphold various moral-ethical issues as defined in the IPENZ code of conduct, as will be discussed further in the paper. The paper also makes several recommendations after coming to the conclusion that engineering factors were most to blame for the accident. These recommendations should help in avoiding any further accidents.Maintenance of aircraft is an essential part of the aviation system that lends its support to the global aviation industry. With the increasing growth of air traffic, coupled with the stringent needs of commercial schedules, and the increased demands it imposes on the utilization of aircraft, the pressure on maintenance operations regarding on-time performance will go on escalating. This is forecasted to create more windows of opportunity for the occurrence of human error and the eventual breakdown of the systems safety net. Human error in the maintenance of aircraft has become a common causal factor in various air carrier accidents. Unless the industry takes these accidents seriously and learns from them, breakdowns at the maintenance level will occur on a regular basis. Important facts, from a human factors perspective, have been discovered during investigations into these occurrences. The need to follow established procedures of maintenance by all is emphasized. The paper will attempt to determine who was at fault for the accident. .