As part of its practice of re-examining all aspects of the service experience of a particular aircraft whenever an accident occurs, the FAA has become aware of an incident that occurred on a McDonnell Douglas Model MD-11 series airplane. This incident was a failure of the cargo control unit (CCU) assembly due to damage of the printed circuit board (PCB) in the CCU, as a result of an external short to ground on one or more of the power output lines of the alternating current. This failure resulted in overheating of the electrical pins inside the CCU, and the subsequent release of hot gases and flames through the external cover, which ignited a metallized mylar insulation blanket adjacent to the CCU. Such conditions, if not corrected, could result in smoke and fire in the cargo compartment. This incident is not considered to be related to an accident that occurred off the coast of Nova Scotia involving a McDonnell Douglas Model MD-11 series airplane. Thecause of that accident is still under investigation. \n\nOther Related Rulemaking \nThe FAA, in conjunction with Boeing and operators of Model MD-11 series airplanes, is continuing to review all aspects of the service history of those airplanes to identify potential unsafe conditions and to take appropriate corrective actions. This airworthiness directive (AD) is one of a series of actions identified during that process. The process is continuing and the FAA may consider additional rulemaking actions as further results of the review become available. \n\nExplanation of the Requirements of the Rule \nSince an unsafe condition has been identified that is likely to exist or develop on other McDonnell Douglas MD-11 series airplanes of the same type design, this AD is being issued to prevent overheating of the electrical pins inside the CCU and subsequent release of hot gases and flames, which could result in smoke and fire in the cargo compartment. This AD requires the deactivation ofthe forward and center CCU's. \n\nInterim Action \nThis is considered to be interim action. The FAA is currently considering requiring a modification of the CCU assembly would constitute terminating action for the requirements of this AD. However, the planned compliance time for the installation of the modification is sufficiently long so that notice and opportunity for prior public comment will be practicable. \n\nDetermination of Rule's Effective Date \nSince 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. \n\nComments Invited \nAlthough 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 commenton this rule by submitting such written data, views, or arguments as they may desire. Communications shall 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. \n\nComments 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 ofthis AD will be filed in the Rules Docket. \n\nCommenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2000-NM-61-AD." The postcard will be date stamped and returned to the commenter. \n\nRegulatory Impact \nThe regulations adopted herein will not have a substantial direct effect 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, it is determined that this final rule does not have federalism implications under Executive Order 13132. \n\nThe FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it 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." \n\nList of Subjects in 14 CFR Part 39 \nAir transportation, Aircraft, Aviation safety, Safety. \n\nAdoption of the Amendment \nAccordingly, 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: \n\nPART 39 - AIRWORTHINESS DIRECTIVES \n1. The authority citation for part 39 continues to read as follows: \nAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§ 39.13 (Amended) \n2. Section 39.13 is amended by addingthe following new airworthiness directive: