While pilots generally know that weather information is five minutes old, the actual age can be much older, the National Transportation Safety Board said in a safety alert. That "could mean the difference between life and death" in rapidly changing weather conditions, said NTSB Chairwoman Deborah A.P. Hersman.
The problem affects thousands of general aviation aircraft, ranging from small two-seat aircraft to large corporate jets, which use Next Generation Radar, or NEXRAD, systems. It does not impact large commercial jetliners, which use other weather-monitoring systems.
Old weather information may have played a role in at least two fatal crashes in recent years, the NTSB said.
In March of 2010, a med-evac helicopter crashed in Tennessee when the pilot tried to beat a storm back to his home base. And in December of 2011, a Piper PA-32 suffered an in-flight breakup in stormy weather near Bryan, Texas.
In each case, the NTSB said, the pilots may have misinterpreted a time stamp on the weather monitor. The time stamps indicated the one-minute time interval used to create the image, and not the actual age of the data used to create the image.