Washington (CNN) -- Is a 50% jump in errors by air traffic controllers evidence of a dangerous, mistake-prone work force?
Or is it evidence that a new reporting system, which ultimately may make flying safer, is working?
The Department of Transportation's inspector general says he will try to find out.
At the request of Congress, the Office of Inspector General said it is launching an investigation into the increase in "operational errors" -- the term used when a controller fails to maintain safe distances between planes.
According to Federal Aviation Administration statistics, the number of errors has increased by more than 50% in fiscal 2010.
The FAA contends the increase is mostly due to a new reporting system known as the Air Traffic Safety Action Program. The voluntary system allows controllers to report errors without fear of punishment under most circumstances. Advocates say the system helps the FAA learn of errors, recognize trends and address them.
The FAA also recently implemented the System Loss of Standard Separation Index, designed to identify incidents where there is a loss of separation between aircraft.
The inspector general said it is auditing both programs at the request of Congress