Notice of Proposed Rulemaking

Comment on [Docket No. FAA-2005-23500; Directorate Identifier 2005-NE-46-AD] RIN 2120-AA64 This proposed AD involves a component identified by nomenclature as an air seal for the second stage high pressure turbine of V2500 engines. The part is not identified by part number. According to our records there may be a part approved under CFR 14 § 21.303 that can replace the OEM part. That part is identified as P/N M2A2335-01 approved as a replacement for the IAE P/N 2A2335-01 under McClain International PMA Supplement no. 63, dated 5/20/2002 at page 3. The design approval method is "Test and Computation" indicating that the PMA part may be similar, but not identical to the OEM part. (The PMA supplement page is submitted herewith.) The intent of the proposed AD is therefore unclear whether or not it is contemplated to apply to this particular part numbered part, and if so, whether it applies to just the OEM part or to the PMA part as well. We request clarification of intent. We might also suggest that part numbers be cited in AD's whenever possible and appropriate to reduce or eliminate ambiguity. Bear in mind that not everyone has ready access to the service bulletins so adding the part number to the AD helps MARPA, MRO's and part purveyors to monitor defects. Jack Buster AD Committee Modification and Replacement Parts Association (MARPA)