Fewer Runway Excursions in 2009

The 2009 picture of fatal accidents in worldwide commercial aviation showed no overall improvement from 2008, but in one important category, there was good news. Runway excursion accidents — targeted by the Flight Safety Foundation Runway Safety Initiative and the Runway Excursion Risk Reduction Toolkit — were fewer, according to newly released data from Boeing Commercial Airplanes.¹

Twelve of the 62 total accidents, or 19 percent, were overruns or veer-offs, both classified as runway excursions.² Of the 53 accidents in 2008, 16 — 30 percent — were runway excursions. In 2007, the Boeing data included 10 excursions, 26 percent of the 38 total accidents.

One of the 2009 excursion accidents involved fatalities, compared with three in 2008. Some of the latest excursions involved equipment failures rather than faulty takeoffs or approaches. One excursion resulted from the inability to fully extend the left main landing gear; another, right main landing gear failure and collapse; a third, engine thrust-­reverser failure and uncoordinated thrust.

Four of the 2009 excursions, one-third, were classified as major accidents, a category that partially overlaps with the fatal accident category.³ Six of the excursions in 2008 — 38 percent — were major accidents.

The 37 approach and landing accidents (ALAs) accounted for 60 percent of the 2009 total, compared with 31 — 58 percent — in 2008 and 23 — 61 percent — in 2007. Although ALAs as a percentage of the total number of accidents have not changed by more than three percentage points in the past three years, their consequences were less severe in 2009. Four of the ALAs in 2009, or 11 percent, involved fatalities. The corresponding percentages for 2008 and 2007 were 19 percent and 22 percent, respectively.

Most of Boeing’s data in its annual accident summaries concern the most recent year plus the previous nine years, thus offering a chance to compare successive 10-year periods. For example, the 2008 report included 1999 through 2008 numbers; the 2009 report comprises 2000 through 2009. In 2000–2009, the fatal accident rate for scheduled commercial passenger operations was 0.42 per million departures, compared with 0.45 in 1999–2008 and 0.50 in 1998–2007.

The 10-year period beginning in 2000 included 301 accidents in passenger operations, a 6 percent increase over the 283 in 1999–2008 and a 5 percent increase above the 286 in the 1998–2007 stretch. The increases in the latest 10 years included both scheduled operations and charter flights, 6 percent and 17 percent respectively. Accidents in cargo operations increased in the most recent period from 79 to 81, or by 3 percent.

Fatal accidents in 2000–2009 numbered 72, 5 percent fewer than the 76 in the previous period and 8 percent fewer than in the 78 in 1998–2007. The 69 fatal accidents in scheduled service compared with 74 in the previous period, a 7 percent improvement. The number of fatal charter accidents held steady at three.

There were 4,942 on-board fatalities from 2000 to 2009, compared with 4,670 from 1999 to 2008, a 6 percent difference. That included an increase in fatalities during scheduled operations from 4,666 to 4,938. There were four fatalities in charter operations in both periods.

Among all the accidents in 2000–2009, 23 percent involved fatalities. The corresponding ratio for 1999–2008 and 1998–2007 was 25 percent. The fatal-accident proportion from 1959–2009, comprising most of the years of passenger-jet service, was 35 percent.

Among the 304 nonfatal accidents in the latest 10-year period, 292 — 96 percent — involved either hull loss or substantial damage.⁴ A smaller proportion — 85 percent — of fatal accidents involved hull loss or substantial damage. The comparable numbers for 1999–2008 were 97 percent and 86 percent, respectively.

Boeing tabulated fatalities according to the U.S. Commercial Aviation Safety Team/International Civil Aviation Organization (CAST/ICAO) standard taxonomy.⁵ “Loss of control in flight” (LOC-I) and “controlled flight into terrain” (CFIT) continued to be involved in the greatest number of fatalities in the most recent 10 years. However, loss of control on-board fatalities were 1.8 to 2.0 times higher than CFIT fatalities in the most recent 10-year periods. In 2000–2009, there were 1,759 LOC-I on-board fatalities and 961 CFIT fatalities. For 1999–2008, the numbers were 1,926 and 961, respectively; for 1998–2007, 1,984 and 1,137 respectively.

The combined category “runway excursion — landing” plus “abnormal runway contact” plus “undershoot/overshoot” resulted in 606 on-board fatalities in the 2000–2009 period, an increase of 49 percent over the 408 in 1999–2008. In the “system component failure — non‑powerplant” category, the latest 10-year period had 314 on-board fatalities, or 26 percent fewer than the 426 in the previous 10-year period. There was a surge of “unknown or undetermined” accident on-board fatalities, from 120 in 1999–2008 to 504 in 2000–2009.

Notes

1. Boeing Commercial Airplanes. Statistical Summary of Airplane Accidents: Worldwide Operations, 1959–2009. Available via the Internet at www.skybrary.aero/bookshelf/books/2725.pdf.
2. The data are limited to commercial jet airplanes over 60,000 lb (27,216 kg) maximum gross weight. Airplanes manufactured in the Soviet Union or Commonwealth of Independent States are excluded because of the lack of operational data.

   An airplane accident is defined as “an occurrence associated with the operation of an airplane that takes place between the time any person boards the airplane with the intention of flight and such time as all such persons have disembarked, in which death or serious injury results from being in the airplane; direct contact with the airplane or anything attached thereto; or direct exposure to jet blast; the airplane sustains substantial damage; or the airplane is missing or completely inaccessible.” Occurrences involving test flights or resulting from hostile action such as sabotage or hijacking are excluded.

3. Boeing defines a major accident as one in which any of three conditions is met: the airplane was destroyed; there were multiple fatalities; or there was one fatality and the airplane was substantially damaged. Flight Safety Foundation supports the use of this term to designate the most severe accident category in preference to the traditional term hull loss, which the Foundation believes is more significant for insurance actuarial purposes than as a measure of risk.
4. Substantial damage is “damage or failure which adversely affects the structural strength, performance or flight characteristics of the airplane, and which would normally require major repair or replacement of the affected component.”
5. The taxonomy is described at www.intlaviationstandards.org.

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