Flying Seasons

Surfing for Safety Stats

December 1, 2007

A mountain of data all for a mouse click

For the past 12 months we've been reviewing the seasonal challenges that pilots face throughout the course of a year. We've reviewed slippery runways, icing conditions, turbulence, crosswind landings, maintenance issues related to airplane inactivity, pilot currency, thunderstorms, density altitude, bird/deer/bull/elk strikes, and inadvertent—or perhaps intentional—flights into instrument meteorological conditions when pilots were unprepared for the risks they faced. It was a solid review of the major weather-related safety issues that all pilots must confront.

Each article opened the educational window a little wider on each of the seasonal risks. Accidents involving structural icing, we learned, were relatively rare, with a mere two fatal accidents in 2006. But the pilots in both those accidents had lots of piloting time and experience in complex airplanes. As for turbulence, we read about one lucky pilot who encountered extreme turbulence while flying his Mooney, lost control in instrument conditions, plunged 10,000 feet in an uncontrolled descent, then pulled 12 Gs in a spar-bending recovery. And when it comes to crosswinds, it's not just student pilots who have trouble; we read how a FedEx DC-10 captain landed so hard in a botched crosswind landing that the landing gear collapsed and a fire broke out.

In an affirmation of the advice to learn from others' mistakes, the articles drew heavily upon a valuable source of accident records—the AOPA Air Safety Foundation's accident database. This database, which uses information from the NTSB, is available online via the "AOPA Air Safety Foundation" link at the top of AOPA's home page. Clicking that link lets you access several popular sites: an accident database, popular database searches, featured accidents, the annual Nall Report on general aviation accidents, special reports, and accident statistics.

Although quite comprehensive, these databases are very easy to navigate. They're much more accessible than the NTSB's own online accident database.

Our authors' methods of accessing accident data involve searching the database directly. On the AOPA Air Safety Foundation page, click the "Accident Analysis" link on the left side. On the Accident Analysis page, click the "ASF Accident Database" link. On the resulting page, click the "Search the ASF Accident Database!" link, and you're ready to define the parameters of your search. The search can be tailored by various information categories.

For my article on icing accidents I selected "Specific Date Range" in the Date Range drop-down list and entered January 1, 2006, and December 31, 2006, in the Start Date and End Date fields. I then selected "Factory Built" in the Type field; chose "All Makes," "All Models," "All States;" selected "Fatal" from the Highest Injury drop-down list; selected "All Types of Flight" in the Flight field; and selected "All" in the Basic Weather and Light Conditions fields. Finally, I selected "Structural Icing" in the Keyword field. Then I selected "15" in the Results Per Page field. Now go ahead, you try it. You'll see the two accidents I referred to in the article: a Cirrus SR20 in Colorado, and a Cessna 421 in Washington.

To read more complete NTSB summaries of the accidents, click the links in the NTSB Number column. The full reports, complete with probable causes, pop up for you to read or print. In some cases, however, full reports aren't yet available, so complete information and probable causes do not appear. (It can take up to two years for the NTSB to come out with an official probable cause.) Instead, you see preliminary reports, or more complete factual reports as the investigations get under way.

Those wanting quicker searches can click the "Popular Database Searches" link on the Accident Analysis page and select from the listings of broad accident categories then presented, including Stall/Spin accidents and Instructional Accidents, among others.

The AOPA ASF accident database starts in 1983 and continues to the present, so there's a lot of material available for the clicking. It's all free, and it's yet another of the many ASF accident awareness tools posted online.

E-mail the author at tom.horne@aopa.org.