The National Air Transportation Association (NATA) is distributing free diesel exhaust fluid (DEF) decals as the association continues to highlight the need for proper training and handling of the substance that has been involved in jet-A contamination incidents and led to in-flight emergencies. The decals are intended to clearly label DEF storage containers to reduce the possibility of mistaking DEF for other liquids such as fuel-system icing inhibitors.
NATA created a free DEF contamination prevention training course after a 2017 contamination incident. But this past spring another incident of DEF contamination was believed to have caused the loss of power in the engines of two Cessna Citations. These incidents spurred the NTSB to issue a safety alert on the dangers of DEF contamination and prompted NATA to reiterate the need for training on DEF use and handling. “FBOs and aircraft operators must be diligent in ensuring that staffs are not only properly trained, but that company policies and procedures used to prevent DEF contamination are being followed,” NATA said.
DEF is required for newer on- and off-road diesel-powered vehicles, making it more prevalent on airfields as refueling trucks are replaced. When combined with jet-A, DEF forms crystalline deposits in aircraft fuel systems.