The Rijksluchtvaartdienst (RLD), which is the airworthiness authority for the Netherlands, recently notified the FAA that an unsafe condition may exist on certain Fokker Model F28 Mark 0100 series airplanes. The RLD advises that it has received reports indicating that, during scheduled visual inspections of the cargo door area, fatigue cracking of the hinges of the forward, center, and rear cargo doors were found. This cracking occurred much earlier than anticipated by fatigue analysis and test results. Therefore, the threshold for inspection of the cargo door hinges specified in the Airworthiness Limitations Items (ALI) and Maintenance Review Board (MRB) task numbers 523052-00-02 and 523052-00-03 may need to be adjusted. Investigation is continuing to determine if other factors (such as a jamming cargo net at the door hinge, a cargo door that slams against the fuselage when it is opened, etc.) may have contributed to the cracking of the hinges.
Fatigue cracking of the hinges of the cargo doors, if not detected and corrected in a timely manner, could result in structural failure of the cargo doors, and consequent rapid decompression of the airplane and possible separation of the cargo doors from the airplane during flight.
Explanation of Relevant Service Information
Fokker has issued Service Bulletin SBF100-52-061, dated September 28, 1996, which describes procedures for a one-time inspection to detect fatigue cracking of the hinges of the cargo doors. The service bulletin also provides a form for operators to report the results of the one-time inspection. The RLD classified this service bulletin as mandatory and issued Dutch airworthiness directive (BLA) 1996-125 (A), dated September 30, 1996, in order to assure the continued airworthiness of these airplanes in the Netherlands.
FAA's Conclusions
This airplane model is manufactured in the Netherlands and is type certificated for operation in the United States under theprovisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.19) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the RLD has kept the FAA informed of the situation described above. The FAA has examined the findings of the RLD, 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.
Explanation of Requirements of the Rule
Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, this AD is being issued to require a one-time inspection to detect fatigue cracking of the hinges of the cargo doors, and repair, if necessary. This AD also requires that operators submit a report of the findings of the one-time inspection required by this action to the airplane manufacturer. The information obtained from these reports will enable the manufacturer to determine if other factors may have contributed to the fatigue cracking of the hinges. The inspections are required to be accomplished in accordance with the service bulletin described previously. Repair of any fatigue cracking detected, is required to be accomplished in accordance with a method approved by the Manager, Standardization Branch, ANM-113.
Interim Action
This is considered to be interim action until final action is identified, at which time the FAA may consider further rulemaking.
Cost Impact
None of the Model F28 Mark 0100 series airplanes affected by this action are on the U.S. Register. All airplanes included in the applicability of this rule currently are operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, the FAA considers that this rule is necessary to ensure that the unsafe condition is addressed in the event that any of these subject airplanes are imported and placed on the U.S. Register in the future.
Should an affected airplane be imported and placed on the U.S. Register in the future, it would require approximately 2 work hours to accomplish the required actions, at an average labor charge of $60 per work hour. Based on these figures, the cost impact of this AD would be $120 per airplane.
Determination of Rule's Effective Date
Since this AD action does not affect any airplane that is currently on the U.S. register, it has no adverse economic impact and imposes no additional burden on any person. Therefore, prior notice and public procedures hereon are unnecessary and the amendment may be made effective in less than 30 days after publication in the Federal Register.
Comments Invited
Although this action is in the form of a final rule and was not preceded by notice and opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submittingsuch 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.
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 inthe Rules Docket.
Commenters 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 97-NM-149-AD." The postcard will be date stamped and returned to the commenter.
Regulatory Impact
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.
For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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: