Air Disasters: Dramatic black box flight recordings. Malcolm MacPherson

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      Indeed, there has been no major aircraft crash in the last seven years in the USA. That’s safety to bank on. Indeed, 2007 was a typically excellent year. With 4.65 billion air passengers travelling worldwide (769 million on aeroplanes based in the US), 965 people died of all causes in 136 incidents, which were 28 fewer than in 2006, with a 25 per cent decrease in fatalities (and none of these, in fact, included commercial aviation). In the United States 95 per cent of transportation fatalities occur on roads and highways. Waterways and railroad lines account for more fatalities than aviation, which weighs in at a mere 1 per cent of the total for all transportation—or roughly eighty times safer than travel on roads. The time can almost be foreseen when compilations similar to the one you are now reading won’t exist for lack of enough CVR transcripts to put between covers.

      Not surprisingly, the safety trends in the United Kingdom, according to the statistics offered by the Civil Aviation Authority (UK), have run closely in parallel with those in the US. While the number of passengers flying to, from or between UK airports more than quadrupled between 1980 and 2006, from 50 million to 210 million, safety has steadily improved to the point of near statistical perfection. In 2006, 185 million passengers arrived or departed the UK on international flights, while 25 million passengers travelled on domestic flights. And yet fatality rates were less than 1 billion passenger kilometres in all years since 1981 and less than 0.1 per billion since 1990. Within the UK, there was one fatality among airline (and air taxi) passengers reported since 2001 and five among airline crews; UK airlines flying outside the British Isles reported no passenger or crew fatalities between 2000 and 2006. (The reason you will find no UK CVR transcripts in this collection is because there have recently been no fatal accidents to record and transcribe, even if the Air Accidents Investigation Branch, part of the Department of Transport, published CVR transcripts or otherwise made them available to the general public.)

      The airline industry and government bureaucracies continue to work hard to keep flying safe, aware that fallible human beings will always be involved to create risks. Starting on this new book, I was curious to find out why airline fatalities started to decline, almost precipitously, around 1963. I found that by then the aviation industry had switched over from internal combustion engines to much simpler, and thus safer, jet engines. It was also then that the industry started to build redundancies into aeroplanes beyond just multiple engines. Redundancy, at its simplest level, catches failures. On a two-engine airliner, for instance, if one engine fails on takeoff, the aircraft design calls for the remaining engine to propel the entire weight of the aircraft by itself. Duplication was installed wherever possible.

      To this was soon added another safety innovation—the nearly obsessive maintenance of records with which to cross-reference minute and large mechanical and other aircraft failures to forestall other identical (or similar) failures. For instance, when United Airlines DC-10 Flight 232 crashed while attempting to land in Sioux City, Iowa, on 19 July 1989, the NTSB determined post haste that engine failure, and specifically the failure of a single disc in one of the aircraft’s three fanjet engines, had caused the crash. Discs in six engines had been forged from the same alloy ingot, and in a matter of days the other five aircraft with engine discs made from that ingot were identified and grounded, thus eliminating the possibility of a second or third engine failure. That kind of thoroughness is unparalleled.

      Over the years starting around 1963, pilot training improved as well. All cockpit crews today train in sophisticated, aircraft-specific simulators. Before simulator use, pilots necessarily acquired experience in the aircraft in real time, which clearly prevented exploration of the aircraft at the edge of its performance envelopes and beyond to see what would happen. Now, with simulators, pilots can crash aeroplanes over and over again while sitting inside a building. Not long ago, I flew ‘aboard’ a simulator of a Chinook military helicopter (MH-47) through an emergency crash/dive that had nearly killed everyone on board in Afghanistan a couple of years earlier. The helicopter pilot in Afghanistan was my pilot in the simulator at a US Army base, and such was the reality of the experience that even the simulator’s technical minders paled; with lights and horns blaring and the cockpit shaking and controls trembling, and, with mountainous Afghan terrain out of the front window, I did not feel that anything was being simulated. I walked away with the reassurance that cockpit crews are the best prepared and trained for any emergency ever.

      For decades cockpits were considered authoritarian domains. Like that of a captain on board a ship, the word of the captain in the cockpit was law. Crashes and other incidents occurred when the captain failed to listen to a warning from the co-pilot or first officer. Sometimes, first officers did not even bother to speak up when they saw trouble ahead. Slowly, from around the mid-1980s, cockpit crews began to move away from stratification and develop a new structure in which the cockpit ‘team’ became the ruling entity. First officers were encouraged to speak up and captains were instructed to pay attention to them, for the sake of everyone’s safety. Older pilots who felt uncomfortable in this more democratic setting were asked to resign. The atmosphere improved immeasurably and in terms of safety everyone benefited, including the captain.

      At the same time, a vast new array of technology emerged to assist cockpit crews. Technologies that monitor systems, navigate and effectively fly the aeroplane became commonplace in cockpits. And while these tools helped cockpit crews, the individual in the cockpit did not succumb to a natural inclination to rely on technology. Crews today are trained never to let the aeroplane be flown by computers against the pilot’s common sense and experience.

      The weak link in safety is man, but that link can also be a last hope.

      Taking safety an extra step into a realm where any unknown threat can be isolated and examined before an accident occurs, airlines today are making full use of a technology called Flight Operations Quality Assurance (FOQA), first developed in Europe (and known there as FDM or flight data management). FOQA uses flight data stored in quick-access recorders; the data are analyzed every dozen or so flights. Essentially, FOQA enables airlines to search the data for any events or trends that might signal a conflict with normal, or standard, operating procedures. It affords airlines a real-time audit of what’s going on. This can lead to changes that make flying safer. For example, United Airlines routinely examined FOQA data on its aircraft flying to Mexico City, where it noticed that oddly fast approaches to landing had the potential, at least, of causing runway overrun accidents. United wanted to know what was causing the faster approaches, and FOQA told them. Their aircraft were typically being told to turn early, before a designated intersection. That early turn put the aircraft higher—and thus faster—on the approach. Corrections were made and a potential problem was corrected before it actually arose.

      FOQA has also helped to eliminate costly maintenance problems. In one recent example pilots were reporting that they did not know why they were exceeding maximum speeds for deploying wing flaps. The airline analyzed the FOQA data on their aircraft. They reported to these pilots that their speeds were on average only 1 knot or less over maximum. If the airline had gone on the word of the pilots it would have had no other choice but to take the aircraft out of service and disassemble the wing. With FOQA, no such response was necessary and costs were avoided and money saved. Other savings were found through FOQA in gasoline conservation. Conserving only one gallon of AVGAS over a flight by reaching higher altitudes sooner can save an airline tens of millions of dollars a year.

      With the recent rapid growth of demand for airline services, new safety concerns will always occur in spite of efforts to anticipate them. One such current concern is called ‘runway incursion’.

      While concentrating on making air travel safer in the air than on the ground, airports today are experiencing serious congestion problems on runways and taxiways—specifically, incursions. ‘There are more planes but not more cement’, one person associated with analyzing the issue told me. Congestion leads to incursions, which can lead to crashes and fatalities on the ground. The rate of new incursions has alarmed the US Federal Aviation Administration (FAA) and other nations’ oversight groups. In response, СКАЧАТЬ