E7-6121. Airworthiness Directives; Mitsubishi Heavy Industries MU-2B Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to supersede Airworthiness Directives (AD) 93-07-11 and AD 94-04-16, which apply to certain Mitsubishi Heavy Industries MU-2B Series airplanes. AD 93-07-11 and AD 94-04-16 currently require you to reduce the maximum deflection of the elevator nose-down trim to a 1-degree to 3-degree range. When the above AD actions were issued, there was no associated elevator trim indicator change. Without such change, the trim reaches the maximum nose-down limit and the indicator still shows additional nose-down trim available. In attempting to force additional nose-down trim, pilots have manually jammed the trim system preventing subsequent electric trim changes until the pilot manually freed the trim wheel. Consequently, this proposed AD would retain the actions from AD 93-07-11 and AD 94-04-16 and add the action of modifying the elevator trim indicator scale dial to be consistent with the reduced elevator trim capability. We are proposing this AD to prevent the above scenarios from occurring with consequent loss of control.

DATES:

We must receive comments on this proposed AD by June 4, 2007.

ADDRESSES:

Use one of the following addresses to comment on this proposed AD:

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590-0001.
• Fax: [phone].
• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.

For service information identified in this proposed AD, contact Mitsubishi Heavy Industries America, Inc., 4951 Airport Parkway, Suite 800, Addison, Texas 75001; telephone: [phone]; facsimile: 972-934-5488.

FOR FURTHER INFORMATION CONTACT:

Werner G. Koch, Aerospace Engineer, Fort Worth Airplane Certification Office, ASW-150, Rotorcraft Directorate, FAA, 2601 Meacham Boulevard, Fort Worth, Texas 76137-4298; telephone: [phone]; fax: [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments regarding this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number, “FAA-2007-27191; Directorate Identifier 2007-CE-007-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive concerning this proposed AD.

Discussion

Several incidents caused by excessive control wheel force on Mitsubishi Heavy Industries MU-2B series airplanes caused us to issue AD 93-07-11, Amendment 39-8543 and AD 94-04-16, Amendment 39-8836 (59 FR 8520, February 23, 1994). AD 93-07-11 and AD 94-04-16 currently require you to reduce the maximum deflection of the elevator nose-down trim to a 1-degree to 3-degree range on certain Mitsubishi Heavy Industries MU-2B series airplanes.

When the above AD actions were issued, there was no associated elevator trim indicator change. Consequently, when the trim reaches the maximum nose-down limit, the indicator still shows additional nose-down trim available. This condition may result in the pilot thinking that more nose-down trim is available beyond the mechanical stop. In attempting to force additional nose-down trim beyond the mechanical stop, pilots have manually jammed the trim system preventing subsequent electric trim changes until the pilot manually freed the trim wheel. This condition, if not corrected, could result in loss of control.

Relevant Service Information

The following service information was included in AD 93-07-11 and AD 94-04-16 and will remain in effect for this AD:

• Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 079/27-010, dated August 28, 1992; and
• Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 216, dated September 11, 1992.

The above service information describes procedures for reducing the maximum deflection of the elevator nose-down trim to a 1-degree to 3-degree range.

We have reviewed the following service information for this AD:

• Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 091/27-011, dated August 6, 1998; and
• Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 228, dated July 13, 1998.

The above service information describes procedures for modifying the elevator trim indicator scale dial to be consistent with the elevator trim capability.

FAA's Determination and Requirements of the Proposed AD

We are proposing this AD because we evaluated all information and determined that without the elevator trim indicator scale dial modifications the unsafe condition described previously is likely to exist or develop on other products of the same type design. This proposed AD would supersede AD 93-07-11 and AD 94-04-16 with a new AD that would retain the actions from AD 93-07-11 and AD 94-04-16 and add the action of modifying the elevator trim indicator scale dial to be consistent with the elevator trim capability. This proposed AD would require you to use the service information described previously to perform these actions.

Costs of Compliance

We estimate that this proposed AD would affect 400 airplanes in the U.S. registry.

Costs Retained From AD 93-07-11 and AD 94-04-16

We estimate the following costs to do the proposed modification of the elevator nose-down trim:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
6 work-hours × $80 per hour = $480	$300	$780	$312,000

Additional Costs for This AD

We estimate the following costs to do the proposed modification of the elevator trim indicator scale dial:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
1 work-hour × $80 per hour = $80	N/A	$80	$32,000

Authority for this Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the proposed regulation:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the 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.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket.

Examining the AD Docket

You may examine the AD docket that contains the proposed AD, the regulatory evaluation, any comments received, and other information on the Internet at http://dms.dot.gov;​; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone [phone]) is located at the street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

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 FAA proposes to amend 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. The FAA amends § 39.13 by removing Airworthiness Directives (ADs) 93-07-11, Amendment 39-8543 and 94-04-16, Amendment 39-8836 (59 FR 8520, February 23, 1994), and adding the following new AD:

Mitsubishi Heavy Industries: Docket No. FAA-2007-27191; Directorate Identifier 2007-CE-007-AD.

Comments Due Date

(a) We must receive comments on this airworthiness directive (AD) action by June 4, 2007.

Affected ADs

(b) This AD supersedes AD 93-07-11, Amendment 39-8543 and AD 94-04-16, Amendment 39-8836.

Applicability

(c) This AD applies to the following airplane models and serial numbers that are certificated in any category:

(1) Category 1 Airplanes:

Model	Serial Nos.
(i) MU-2B, MU-2B-10, MU-2B-15, MU-2B-20, MU-2B-25, and MU-2B-26	008 through 347 (except 313 and 321).
(ii) MU-2B-30, MU-2B-35, and MU-2B-36	501 through 696 (except 652 and 661).

(2) Category 2 Airplanes:

Model	Serial Nos.
(i) MU-2B-25, MU-2B-26, MU-2B-26A, and MU-2B-40	313SA, 321SA, 348SA through 459SA.
(ii) MU-2B-35, MU-2B-36A, and MU-2B-60	652SA, 661SA and 697SA through 1569SA.

Unsafe Condition

(d) This AD results from several incidents caused by excessive control wheel force. We are issuing this AD to retain the actions of AD 93-07-11 and AD 94-04-16 to prevent excessive control wheel force caused by extreme elevator nose-down trim deflection. We are also issuing this AD to modify the elevator trim indicator scale dial to be consistent with the reduced elevator trim capability. Inconsistencies between the elevator indicator scale dial and the elevator trim mechanical stop may result in the pilot thinking that more nose-down trim is available beyond the mechanical stop. Attempting to force additional nose-down trim beyond the mechanical stop may jam the trim system, preventing subsequent electric trim changes until the pilot manually frees the trim wheel. These conditions may result in loss of control of the airplane.

Compliance

(e) To address this problem, you must do the following, unless already done:

Actions	Compliance	Procedures
(1) Reduce the maximum deflection of the elevator nose-down trim to a 1-degree to 3-degree range	(i) For Category 1 airplanes: Within 100 hours time-in-service (TIS) after April 11, 1994 (the effective date of AD 94-04-16)	(A) For Category 1 airplanes: Follow Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 216, dated September 11, 1992.
	(ii) For Category 2 airplanes: Within 100 hours TIS after June 1, 1993 (the effective date of AD 93-07-11)	(B) For Category 2 airplanes: Follow Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 079/27-010, dated August 28, 1992.
(2) Modify the elevator trim indicator scale dial.	Within 100 hours TIS after the effective date of this AD	(i) For Category 1 airplanes: Follow Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 228, dated July 13, 1998. (ii) For Category 2 airplanes: Follow Mitsubishi Heavy Industries, Ltd., Service Bulletin No. 091/27-011, dated August 6, 1998.

Alternative Methods of Compliance (AMOCs)

(f) The Manager, Fort Worth Airplane Certification Office (ACO), FAA, ATTN: Werner G. Koch, Aerospace Engineer, Fort Worth ACO, ASW-150, Rotorcraft Directorate, FAA, 2601 Meacham Boulevard, Fort Worth, Texas 76137-4298; telephone: [phone]; fax: [phone], has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(g) AMOCs approved for AD 93-07-11, Amendment 39-8543 and AD 94-04-16, Amendment 39-8836 are approved for this AD.

Related Information

(h) To get copies of the service information referenced in this AD, contact Mitsubishi Heavy Industries America, Inc., 4951 Airport Parkway, Suite 800, Addison, Texas 75001; telephone: [phone]; facsimile: 972-934-5488. To view the AD docket, go to the Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC, or on the Internet at http://dms.dot.gov. The docket number is Docket No. FAA-2007-27191; Directorate Identifier 2007-CE-007-AD.

Issued in Kansas City, Missouri, on March 27, 2007.

Kim Smith,

Manager, Small Airplane Directorate, Aircraft Certification Service.