CESSNA 550 Citation II — Airworthiness Directives

This document is a Safety Alert for Operators (SAFO) issued by the FAA, specifically addressing the issue of jet fuel contaminated with Diesel Exhaust Fluid (DEF). It serves to inform aircraft operators, Fixed-Base Operators (FBOs), and repair stations about incidents where aircraft were fueled with contaminated jet fuel, leading to operational malfunctions and emergency landings. The document details several case studies, including incidents involving Cessna Citation 550 aircraft, and provides recommendations for actions to mitigate risks associated with DEF contamination. The FAA emphasizes the importance of proper fueling procedures and the need for operators to communicate with fuel providers to prevent future contamination events.

• Cessna Citation 550 aircraft have experienced engine flameouts due to jet fuel contaminated with DEF.
• DEF is a urea-based chemical that should never come into contact with aviation fuel.
• Operators must discard any jet fuel suspected of being contaminated with DEF to prevent operational issues.
• Proper communication with fuel providers is essential to mitigate risks of fuel contamination.