AD 97-17-05

Transport Canada, which is the airworthiness authority for Canada, recently notified the Federal Aviation Administration (FAA) that an unsafe condition may exist on Pratt & Whitney Canada (PWC) PW118, PW118A, PW118B, PW119B, PW119C, PW120, PW120A, PW121, PW121A, PW123, PW123B, PW123C, PW123D, PW123E, PW124B, PW125B, PW126A, PW127, PW127E, and PW127F series turboprop engines. The FAA and Transport Canada received a report of an Embraer EMB-120 aircraft powered by PWC PW118B turboprop engines that recently experienced a fire shortly after take off. The aircraft landed safely with the loss of both hydraulic systems and with extensive heat and fire damage to the right engine nacelle, wing, and landing gear bay. A portion of the aircraft exhaust duct was also missing. The fuel and ignition sources have not been determined and the investigation of the accident by the National Transportation Safety Board (NTSB) is continuing. As part of the investigation, theright engine was disassembled and the investigators found the gas generator case rear drain port was not capped as required by the aircraft manufacturer's installation instructions. A subsequent inspection of the operator's EMB 120 fleet found two more aircraft with the cap missing from the gas generator case rear drain port. Under certain conditions, the opened rear drain port may permit fluid to exit through the port and accumulate in the nacelle resulting in a possible hazardous situation. All PW100 model engines are equipped with two gas generator case drain ports. This condition, if not corrected, can result in a nacelle fire caused by fluid leaking from the gas generator case drain ports. PWC has issued Service Information Letter SIL No. PW100-003, issued June 18, 1997, that describes procedures for a visual inspection of the two gas generator case drain ports to ensure that they are connected to drain lines or capped in accordance with the applicable aircraft installationconfiguration. This engine model is manufactured in Canada and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, Transport Canada has kept the FAA informed of the situation described above. The FAA has examined the findings of Transport Canada, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States. Since an unsafe condition has been identified that is likely to exist or develop on other engines of the same type design registered in the United States, the proposed AD would require a visual inspection of the two gas generator case drain ports to ensure that they are connected to drain lines or capped in accordance with the applicable aircraft installation configuration. The actions would be required to be accomplished in accordance with the SIL described previously. Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days. Comments Invited Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 97-ANE-32-AD." The postcard will be date stamped and returned to the commenter. The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: PART 39 - AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: