EASA SIB NM-13-19
Hawker Beechcraft 400, 400A and 400T Aeroplanes — Airfoil Anti/De-ice System
Summary
Special Airworthiness Information Bulletin SAIB: NM-13-19 is an FAA informational bulletin addressing an airworthiness concern with the Metal Oxide Semiconductor Field Effect Transistor (MOSFET) contactors used in the horizontal stabilizer de-ice system on Hawker Beechcraft 400, 400A, and 400T aeroplanes. The affected aircraft include Hawker 400 models with serial numbers RJ-1 through RJ-65, Hawker 400A models with serial numbers RK-1 through RK-379, and Hawker 400T models with serial numbers TX-1 through TX-13. This bulletin provides guidance on inspection and replacement procedures for the MOSFET contactors to prevent overheating and failure.
What Changed
This bulletin introduces awareness of a potential failure mode where the MOSFET contactor in the horizontal stabilizer de-ice system can develop an internal short causing overheating and inoperative de-ice function. It references Hawker Beechcraft Service Bulletin SB 30-4073 and Kit 128-3065 for inspection and replacement guidelines. No mandatory airworthiness directive is issued, but recommended procedures and preflight checks are highlighted.
Why It Matters
This information is important for operators and maintenance personnel to ensure the horizontal stabilizer de-ice system functions correctly, preventing potential in-flight icing hazards. Early detection and replacement of faulty MOSFET contactors reduce the risk of system failure and heat damage. Compliance with the recommended service bulletin enhances flight safety and operational reliability without imposing regulatory mandates.
What To Do
Owners and operators of affected Hawker Beechcraft 400 series aircraft should follow the inspection and replacement guidelines outlined in Service Bulletin SB 30-4073 and Kit 128-3065 issued by Hawker Beechcraft. They should also perform the preflight procedures to verify proper system operation and adhere to emergency procedures in the flight manual if the "H STAB ICE FAIL" annunciation occurs. There is no specified compliance deadline, but timely action is advised.