Summary
We propose to adopt a new airworthiness directive (AD) for certain Rolls-Royce Deutschland Ltd & Co KG (RRD) BR700-710A2-20 and BR700-710C4-11 turbofan engines. This proposed AD was prompted by reports of deterioration of the intumescent heat resistant paint system on the electronic engine controller (EEC) firebox assembly that was found to be beyond acceptable limits. This proposed AD would require replacement of affected EEC firebox assembly parts with improved parts, which have a more durable paint system. We are proposing this AD to address the unsafe condition on these products.