The AOPA Air Safety Foundation warned on March 24 that it is “too soon to be making guesses about the cause of Sunday’s accident in Montana,” saying investigators are still in the data collection phase, which is only the first in a long series of steps toward determining a cause.
“It’s important to remember that, except for the extremely rare single-point catastrophic failure, aviation accidents are almost invariably the result of a chain of events and decisions,” said Air Safety Foundation President Bruce Landsberg. “The National Transportation Safety Board is extremely good at accident reconstruction, but it will take months to find, and then unravel, all the links in this accident’s chain.”
National Transportation Safety Board aviation investigations follow “a predictable arc,” he said. First, investigators collect all available information. They speak to any available witnesses, retrieve data on the weather at the time and location of the accident, and learn what they can about the pilot and his or her experience level. In high profile accidents such as Sunday’s, investigators may hold briefings to discuss the information they have collected, which is then collated into a preliminary report.
“The briefings and the preliminary report are nothing more – or less – than a listing of the facts collected,” Landsberg said. “They give no relative weight to any of the facts, nor do they draw any conclusions about possible causes.”
Following the preliminary investigation, NTSB staff members begin a painstaking review of all available evidence. They work with stakeholders such as the aircraft’s manufacturer, to draw on outside expertise. At the end of that exhaustive process, usually six to twelve months after the accident, the staff issues a factual report. The report is given to the Board members themselves, who then determine the probable cause of the accident.
“It is the policy of the Air Safety Foundation and the Aircraft Owners and Pilots Association not to comment on a specific accident until the NTSB has issued at least its factual report, and preferably its final report, but we will discuss general information about a type of aircraft or operation,” Landsberg concluded. “Given the complexity of most accidents, we believe that it’s the only prudent approach, and urge others to do the same.”