Embraer Legacy 450/500 operators should be aware of corrosion issues in HTF TRUs coated with CA8000 on the TRU doors and beams of the inner washed gas path surfaces.  

Honeywell has introduced the Mapaero coating as an improved protective coating applied to the gas path surfaces of the TRU.

• SIL AS907 Thrust Reverser Unit (TRU) – MAPAERO Overview: New Service Information Letter issued from HW changing the top coat from the old CA8000 material to the Mapaero XS420 Black Top Coat
• Repair Scheme no 433 Rev D: TR inspection and repair process, this is the current revision updating the paint from CA8000 to the Mapaero topcoat
• GKN-TV-19182 Issue 3 – 3rd Sept-20_sign_28Sep20: Letter from GKN for instructions to obtain a Technical Variance and Fly-On if repair cannot be completed during current MX event

Operators should be aware that the Mapaero XS420 Black Top Coat has a long lead time and should plan ahead if addressing this repair outside of the 60-month inspection.   Expect a lead time of 3 weeks to complete permanent repair which includes TR bucket R&R, removal of corrosion, measurements/NDT and repainting of TR buckets.