Worldwide airline fatal accidents in the first six months of 2013 maintained the all-time best figure of nine, while the number of fatalities involved has set a new low at 58.
Such a short period has limited statistical significance in its own right, especially since safety has become so good that the numbers are tiny, but in comparison with the same period in each year for the last decade, the trend shows that an established gradual improvement is being maintained. Last year's total of nine fatal accidents matched the decade low and compared with 12 in the same period in 2011.
Accidents included in this survey cover all airline operations, whether passenger or cargo, scheduled or charter, on revenue service or positioning flights. A complete non-fatal listing is not attempted, as there are enormous numbers of minor incidents, so it just includes accidents or incidents that are significant in their own right or illustrate a trend or phenomenon - like runway excursion, the most common accident type.
The very low fatalities figure this year so far will probably prove to be a matter of chance. The first six months of last year was more typical, with 338 casualties in the period. The low figure results from the fact that none of the passenger aircraft that crashed happened to be large, and they were carrying small passenger loads. Nevertheless, crash survivability in modern hulls continues to be a favourable factor. The Lion Air Boeing 737-800 that crashed into the sea short of the runway at Denpasar in Indonesia saw injuries among its seven crew and 101 passengers, but no fatalities (see accident list). Another demonstration of remarkable survivability took place in earl July - just outside the period under study - when the tail of an Asiana Boeing 777-200ER approaching San Francisco airport hit the sea wall short of runway 28L. This caused separation of the entire empennage, but 304 of the 307 people on board the aircraft survived the subsequent crash and fire.
In general terms, the more serious accidents this year so far follow an established pattern: most of them happen to small operators in developing economies. However, the USA has departed from that precedent this year with three fatal accidents to N-registered aircraft operating as freighters. One involved a National Air Cargo Boeing 747-400F, lost just after taking off from Bagram air base in Afghanistan. The event was caught on camera, showing a spectacular and distressing total loss of control before the aircraft fell to earth and exploded. The cause is unknown yet, but the inevitable speculation surrounding the event suggests centre of gravity problems. The aircraft was carrying a load bound for the USA.
Unusually, there were no fatal accidents involving regional or commuter airline passenger turboprop operations, but five cargo turboprops crashed fatally, and the majority of the listed non-fatal accidents involved turboprop-powered aircraft. In fact, there were only two jets in the entire fatal accidents listing - a Bombardier CRJ200 during winter operations in Kazakhstan, and the National Air Cargo 747F.
SUMMARY OF OFFICIAL ACCIDENT REPORTS PUBLISHED IN JANUARY-JUNE 2013
A 21 October 2009 Boeing 707 freighter crash at Sharjah, United Arab Emirates, resulted from aggravated crew mishandling of the aircraft following the separation of engine cowls from the No 4 power unit soon after take-off from runway 30, according to the UAE General Civil Aviation Authority. All six crew died in the accident. The 40-year-old aircraft (ST-AKW), operated by Sudanese carrier Azza Air Transport, did not have any working flight recorders, so the GCAA investigation used radar information and tower voice recordings plus witness reports. When the cowls - which had not been properly fastened - separated, they cut a cable providing data to the No 4 power unit's EPR (engine pressure ratio) gauge, leading the crew to conclude - incorrectly - that there had been an engine failure. The crew requested a return after "losing No 4 engine", but they did not compensate for the extra drag from the unclad engine, and the right wing dropped. The crew increased the right bank well beyond the 15˚ limit for the aircraft's initial climb configuration, probably in an attempt to return for landing. The pilot flying increased power and attempted to pitch up, but the GCAA said this probably caused an accelerated stall, and the right wing dropped further. The aircraft eventually developed approximately 90˚ right bank and dived into the ground. Radar data suggests the maximum height reached was 380ft (116m), and the maximum groundspeed was 149kt (276km/h). The authority noted that the condition of the aircraft and engines demonstrated the application of substandard maintenance techniques, but analysis ruled out the operation of asymmetric reverse thrust as a factor in the accident.
Russian investigator MAK said the pilots of a Petropavlovsk-Kamchatsky Aviation Enterprise Antonov An-28 involved in a controlled-flight-into-terrain accident on 12 September 2012 had alcohol in their bloodstream, and that the aircraft should have had a terrain awareness and warning system rather than a simple ground-proximity warning system. The crew carried out what was supposed to be a let-down, according to the published non-directional beacon approach to runway 11 at its destination of Palana, but they provided air traffic control with an incorrect position and made up their own "arbitrary" approach procedure, during which the aircraft hit high ground, killing the crew of two and eight of the 12 passengers.
There have been three accidents affecting AVIC Xian MA60 turboprops in 2013 so far, one involving Indonesian domestic carrier Merpati Nusantara Airlines and two involving Myanmar Airways. Indonesia has declared that it is carrying out an audit into operations of the Chinese-manufactured twin turboprops in Indonesia, and says it intends to ground the aircraft in stages for inspection when the operational audit is complete. Merpati is the only Indonesian operator of MA60s.
The Australian Transport Safety Board's report on the Qantas QF32 accident involving an Airbus A380 uncontained engine failure south of Singapore in November 2010 included a primary recommendation that the certification regulations concerning uncontained engine failure be reviewed, because the turbine disk failure in the Rolls-Royce Trent engine caused greater damage than had previously been seen or predicted. Other recommendations about manufacturing quality control at R-R and the robustness of oil and fuel feed tubes on similar engines from all the manufacturers have largely already been carried out, said the ATSB. Generally, it was satisfied with the way the A380's electronic centralised aircraft monitor presented information to the crews in a complex, multiple-failure scenario, judging this to be "manageable" by the crew.
Nigeria's Accident Investigation Bureau (AIB) has recently released a clutch of accident reports, some of which were well overdue by normal standards. The first involved the Bellview Airlines Boeing 737-300 that crashed while climbing out from Lagos on 22 October 2005. The report said the aircraft had so many defects it was not fit for flight and should not have been dispatched. For reasons that are unclear, the AIB was not able to recover the aircraft's recorders, so the cause of the accident is not fully understood. Both pilots' records of flying hours and training history were found to be unreliable. After take-off from runway 18L at Lagos they turned right to head for Abuja, and were asked to report passing FL130. That was the last contact, and there was no emergency call.
At Lagos, Nigeria, on 7 September 2006, a heavily laden DHL Boeing 727F made an approach in a heavy squall with 600m visibility. It was flying 30kt faster than its approach reference speed, landed halfway along runway 18L and overran it, destroying the ILS localiser antenna. The crew were not injured.
At Abuja, Nigeria, on 29 October 2006, an ADC Airlines Boeing 737-200 crashed almost immediately after take-off. The AIB report says that during taxiing, an approaching rainstorm was creating gusty conditions and the crew would have been well advised to delay departure until the storm had passed.At take-off, the aircraft rotated at 133kt, 5kt less than the correct speed. Some 6s after the gear had been retracted, the windshear warning alert was triggered as the airspeed dropped by 25kt to around 137kt because the headwind had rapidly changed direction to become a tailwind. The crew initially made a nose-down elevator input, but then quickly commanded a pitch-up to about 30-35˚ nose up, inducing a stall. The investigation concluded that the aircraft had sufficient energy to have survived the windshear if the crew had handled it skilfully.