Matthew Mercy

The Rolls-Royce NMSB (72-AF825) referenced in Docket No. FAA-2008-1165' Directorate Identifier 2008-NE-38-AD is baselined from 1st May 2008. After consideration of the FAA proposed Airworthiness Directive, the current structure of the AD is understood to permit the same cyclic draw down as the Rolls-Royce NMSB, however the start date for the applicable draw down is the date of issue of the FAA AD, rather than 1st May 2008. A consequence of this is that the proposed FAA AD would permit service operation longer than the corresponding Rolls-Royce NMSB and EASA AD. Further details of this difference and suggestions have been supplied to the FAA engine specialist James Lawrence (emails 11 March 2009, 20 February 2009). Comments received following publication of the proposed FAA Airworthiness Directive have identified elements of the related Rolls-Royce NMSB which require further review. These have been communicated in full to the FAA engine specialist James Lawrence.