AGENCY:
Federal Aviation Administration, DOT.
ACTION:
Notice of proposed rulemaking (NPRM).
SUMMARY:
This document proposes to supersede Airworthiness Directive (AD) 88-23-01, which currently requires repetitively inspecting torque tube joints for cracks, and, if cracks are found, replacing the joints on all Mitsubishi Heavy Industries, Ltd. (Mitsubishi) MU-2B Series airplanes. AD 88-23-01 resulted from field reports that fatigue cracks were found in the flap control system. A design change exists that could eliminate the need for the repetitive inspections. The proposed AD would require you to replace the existing joints with new improved-design joints as terminating action for the repetitive inspections. The actions specified by this proposed AD are intended to prevent failures of the flap control system due to the existing design torque tube joints. Such failure could lead to loss of control of the aircraft.
DATES:
The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before October 21, 2002.
ADDRESSES:
Submit comments to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2002-CE-27-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. You may view any comments at this location between 8 a.m. and 4 p.m., Monday through Friday, except Federal holidays. You may also send comments electronically to the following address: 9-ACE-7-Docket@faa.gov. Comments sent electronically must contain “Docket No. 2002-CE-27-AD” in the subject line. If you send comments electronically as attached electronic files, the files must be formatted in Microsoft Word 97 for Windows or ASCII text.
You may get service information that applies to this proposed AD from Mitsubishi Heavy Industries America, Inc., 4951 Airport Parkway, Suite 800, Addison, Texas 75001; telephone: (972) 934-5480; facsimile: (972) 934-5488.
You may also view this information at the Rules Docket at the address above.
FOR FURTHER INFORMATION CONTACT:
Direct all questions to:
—For the airplanes manufactured in Japan (Type Certificate A2PC): Carl Fountain, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, 3960 Paramount Boulevard, Lakewood, California 90712; telephone: (562) 627-5222; facsimile: (562) 627-5228; and
—For the airplanes manufactured in the United States (Type Certificate A10SW): Werner Koch, Aerospace Engineer, FAA, Airplane Certification Office, 2601 Meacham Boulevard, Fort Worth, Texas 76193-0150; telephone: (817) 222-5133; facsimile: (817) 222-5960.
SUPPLEMENTARY INFORMATION:
Comments Invited
How Do I Comment on This Proposed AD?
The FAA invites comments on this proposed rule. You may submit whatever written data, views, or arguments you choose. You need to include the rule's docket number and submit your comments to the address specified under the caption ADDRESSES. We will consider all comments received on or before the closing date. We may amend this proposed rule in light of comments received. Factual information that supports your ideas and suggestions is extremely helpful in evaluating the effectiveness of this proposed AD action and determining whether we need to take additional rulemaking action.
Are There Any Specific Portions of This Proposed AD I Should Pay Attention To?
The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of this proposed rule that might suggest a need to modify the rule. You may view all comments we receive before and after the closing date of the rule in the Rules Docket. We will file a report in the Rules Docket that summarizes each contact we have with the public that concerns the substantive parts of this proposed AD.
How Can I Be Sure FAA Receives My Comment?
If you want FAA to acknowledge the receipt of your mailed comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 2002-CE-27-AD.” We will date stamp and mail the postcard back to you.
Discussion
Has FAA Taken Any Action to This Point?
Field reports indicating fatigue cracks were found in the joint of the torque tube assemblies that had been in service for more than 4,000 hours on Mitsubishi MU-2 Series airplanes caused us to issue AD 88-23-01, Amendment 39-6056. This AD requires the following on Mitsubishi MU-2B Series airplanes:
—Repetitively inspecting joints of the torque tube assembly for cracks; and
—Replacing joints if cracks are found.
What Has Happened Since AD 88-23-01 To Initiate This Action?
A recent accident investigation revealed that the improper reinstallation (following an AD 88-23-01 required repetitive inspection) of two cotter pins in the torque tube resulted in a disconnect in the flap drive train. This disconnect resulted in an asymmetrical flap deployment during a landing approach. The pilot lost control of the aircraft, resulting in destruction of the aircraft and death of the pilot.
Is There Service Information That Applies to This Subject?
Mitsubishi has issued:
—Service Bulletin No. 067/27-008A, Revision A, dated March 29, 1995; and
—Service Bulletin No. 189C, Revision C, dated June 28, 1994.
What Are the Provisions of This Service Information?
These service bulletins include procedures for replacing the torque tube assemblies with the improved-design torque tube assemblies.
The FAA's Determination and an Explanation of the Provisions of This Proposed AD
What Has FAA Decided?
After examining the circumstances and reviewing all available information related to the incidents described above, we have determined that:
—The unsafe condition referenced in this document exists or could develop on other Mitsubishi MU-2B Series airplanes of the same type design;
—The actions specified in the previously-referenced service information should be accomplished on the affected airplanes; and
—AD action should be taken in order to correct this unsafe condition.
What Would This Proposed AD Require?
This proposed AD would supersede AD 88-23-01 with a new AD that would eliminate the repetitive inspections by replacing the existing joints with new improved-design joints.
Cost Impact
How Many Airplanes Would This Proposed AD Impact?
We estimate that this proposed AD affects 360 airplanes in the U.S. registry.
What Would Be the Cost Impact of This Proposed AD on Owners/Operators of the Affected Airplanes?
We estimate the following costs to accomplish the proposed replacements:
| Labor cost | Parts cost | Total cost per airplane | Total cost on U.S. operators | |
|---|---|---|---|---|
| 16 workhours × $60 = $960 | $20,000 per airplane | $20,960 per airplane | $20,960 × 360 = $7,545,600 |
What Is the Difference Between the Cost Impact of This Proposed AD and the Cost Impact of AD 88-23-01?
The cost impact of the proposed AD is a one-time cost as shown above. The cost impact of AD 88-23-01 is the cost impact of the repetitive inspections and the eventual replacement cost.
Regulatory Impact
Would This Proposed AD Impact Various Entities?
The regulations proposed herein would 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 proposed rule would not have federalism implications under Executive Order 13132.
Would This Proposed AD Involve a Significant Rule or Regulatory Action?
For the reasons discussed above, I certify that this proposed 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) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action has been placed in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
- Air transportation
- Aircraft
- Aviation safety
- Safety
The Proposed Amendment
Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.
2. FAA amends § 39.13 by removing Airworthiness Directive (AD) 88-23-01, Amendment 39-6056, and by adding a new AD to read as follows:
Mitsubishi Heavy Industries, Ltd.: Docket No. 2002-CE-27-AD; Supersedes AD 88-23-01, Amendment 39-6056.
(a) What airplanes are affected by this AD? This AD affects all serial numbers of Models MU-2B, MU-2B-10, MU-2B-15, MU-2B-20, MU-2B-25, MU-2B-26, MU-2B-26A, MU-2B-30, MU-2B-35, MU-2B-36, MU-2B-36A, MU-2B-40, and MU-2B-60, that are certificated in any category.
(b) Who must comply with this AD? Anyone who wishes to operate any of the airplanes identified in paragraph (a) of this AD must comply with this AD.
(c) What problem does this AD address? The actions specified by this AD are intended to prevent failures of the flap control system due to the existing design of the torque tube joints. Such failure could lead to loss of control of the aircraft.
(d) What actions must I accomplish to address this problem? To address this problem, you must accomplish the following:
| Actions | Compliance | Procedures |
|---|---|---|
| (1) On torque tube assembly part (P/N) 010A-61250, replace joint P/N 010A-61254 with improved-design joint P/N 010A-61254-3 and joint P/N 010-61255-3 with improved-design joint P/N 010A-61255-17 (or FAA-approved equivalent part number), unless already accomplished. | Upon the accumulation of 4,000 hours time-in-service (TIS) on the torque tube assembly or within the next 100 hours TIS after the effective date of this AD, whichever occurs later, unless already accomplished | In accordance with PART 1 of MU-2 Service Bulletin No. 067/27-008A, Revision A, dated March 29, 1995; or PART 1 of MU-2 Service Bulletin No. 189C, Revision C, dated June 28, 1994, as applicable. |
| (2) Replace joint with improved-design joint (or FAA-approved equivalent part number), unless already accomplished: | Upon the accumulation of 4,000 hours of TIS on the torque tube assembly or within the next 200 hours TIS after the effective date of this AD, whichever occurs later, unless already accomplished | In accordance with PART 2 and PART 3 of MU-2 Service Bulletin No. 067/27-008A, Revision A, dated March 29, 1995; or PART 2 and PART 3 of MU-2 Service Bulletin No. 189C, Revision C, dated June 28, 1994, as applicable. |
| (i) on torque tube assembly P/N 010A-61251-11, replace joint P/N 010A-61255-3 with improved-design joint P/N 010A-61255-17 and joint P/N 010-61255-7 with improved-design joint P/N 010A-61255-19; | ||
| (ii) on torque tube assembly P/N 017A-61805, replace joint P/N 010A-61264-3 with improved-design joint P/N 010A-61264-7 and P/N 010-61264-5 with improved-design joint P/N 010A-61264-9; | ||
| (iii) on torque tube assembly P/N 017A-61805-11, replace joint P/N 010A-61264-3 with improved-design joint P/N 010A-61264-7 and P/N 010-61264-5 with improved-design joint P/N 010A-61264-9; | ||
| (iv) on torque tube assembly P/N 010A-61251-31, replace joint P/N 010A-61255-9 with improved-design joint P/N 010A-61255-17 and P/N 010-61255-15 with improved-design joint P/N 010A-61255-23; | ||
| (v) on torque tube assembly P/N 010A-61251, replace joint P/N 010A-61255-3 with improved-design joint P/N 010A-61255-17 and P/N 010-61255-5 with improved-design joint P/N 010A-61255-23; | ||
| (vi) on torque tube assembly P/N 010A-61260, replace joint P/N 010A-61264-3 with improved-design joint P/N 010A-61264-7 and P/N 010-61264-5 with improved-design joint P/N 010A-61264-9; and | ||
| (vii) on torque tube assembly P/N 010A-61260-21, replace joint P/N 010A-61264-3 with improved-design joint P/N 010A-61264-7 and P/N 010-61264-5 with improved-design joint P/N 010A-61264-9. | ||
| (3) Only install joints that are P/N 010A-61254-3, P/N 010A-61255-17, P/N 010A-61255-19, P/N 010A-61255-23, P/N 010A-61264-7, P/N 010A-61264-9, or FAA-approved equivalent P/Ns. Replace all joints at the same time. | As of the effective date of this AD | Not Applicable. |
(e) Can I comply with this AD in any other way?
(1) You may use an alternative method of compliance or adjust the compliance time if:
(i) Your alternative method of compliance provides an equivalent level of safety; and
(ii) The Manager, Fort Worth Aircraft Certification Office, approves your alternative. Submit your request through an FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager.
(2) Alternative methods of compliance approved in accordance with AD 88-23-01, which is superseded by this AD, are not approved as alternative methods of compliance with this AD.
Note:
This AD applies to each airplane identified in paragraph (a) of this AD, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if you have not eliminated the unsafe condition, specific actions you propose to address it.
(f) Where can I get information about any already-approved alternative methods of compliance? Contact:
—For the airplanes manufactured in Japan (Type Certificate A2PC): Carl Fountain, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, 3960 Paramount Boulevard., Lakewood, California, 90712; telephone: (562) 627-5222; facsimile: (562) 627-5228; and
—For the airplanes manufactured in the United States (Type Certificate A10SW): Werner Koch, Aerospace Engineer, FAA, Airplane Certification Office, 2601 Meacham Boulevard, Fort Worth, Texas 76193-0150; telephone: (817) 222-5133; facsimile: (817) 222-5960.
(g) What if I need to fly the airplane to another location to comply with this AD? The FAA can issue a special flight permit under sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate your airplane to a location where you can accomplish the requirements of this AD.
(h) How do I get copies of the documents referenced in this AD? You may get copies of the documents referenced in this AD from Mitsubishi Heavy Industries America, Inc., 4951 Airport Parkway, suite 800, Addison, Texas 75001; telephone: (972) 934-5480; facsimile: (972) 934-5488.
You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.
(i) Does this AD action affect any existing AD actions? This amendment supersedes AD 88-23-01, Amendment 39-6056.
Issued in Kansas City, Missouri, on September 4, 2002.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 02-23289 Filed 9-12-02; 8:45 am]
BILLING CODE 4910-13-P