E6-1769. 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:

The FAA proposes to adopt a new airworthiness directive (AD) for some Mitsubishi Heavy Industries (MHI) MU-2B series airplanes. This proposed AD would require you to change the flight idle blade angle. This proposed AD results from a recent safety evaluation that used a data-driven approach to analyze the design, operation, and maintenance of the MU-2B series airplanes in order to determine their safety and define what steps, if any, are necessary for their safe operation. Part of that evaluation was the identification of unsafe conditions that exist or could develop on the affected type design airplanes. We are issuing this proposed AD to prevent confusion in blade angle settings. This unsafe condition, if not corrected, could lead to an asymmetric thrust situation in certain flight conditions, which could result in airplane controllability problems.

DATES:

We must receive comments on this proposed AD by March 17, 2006.

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.
• Government-wide rulemaking Web site: Go to http://www.regulations.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.

Contact Mitsubishi Heavy Industries, Ltd., 4951 Airport Parkway, Suite 800, Addison, Texas 75001; telephone: [phone]; facsimile: 972-934-5488, for the service information identified in this proposed AD.

You may examine the comments on this proposed AD in the AD docket on the Internet at http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT:

Rao Edupuganti, Aerospace Engineer, Fort Worth ACO, ASW-150, Rotorcraft Directorate, FAA, 2601 Meacham Boulevard, Fort Worth, Texas 76137-4298; telephone: [phone]; facsimile: 817-222-5960.

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on this proposed AD? We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include the docket number, “FAA-2006-23644; Directorate Identifier 2006-CE-03-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 with FAA personnel concerning this proposed rulemaking. Using the search function of the DOT docket Web site, anyone can find and read the comments received into any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Examining the Dockets

Where can I go to view the docket information? You may examine the docket that contains the proposal, any comments received and any final disposition on the Internet at http://dms.dot.gov, or in person at the DOT Docket Offices between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone [phone]) is located on the plaza level of the Department of Transportation NASSIF Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the Docket Management Facility receives them.

Discussion

What events have caused this proposed AD? Recent accidents and the service history of the Mitsubishi MU-2B series airplanes prompted FAA to conduct an MU-2B Safety Evaluation. This evaluation used a data-driven approach to analyze the design, operation, and maintenance of the MU-2B series airplanes in order to determine their safety and define what steps, if any, are necessary for their safe operation.

The safety evaluation provided an in-depth review and analysis of MU-2B accidents, incidents, safety data, pilot training requirements, engine reliability, and commercial operations. In conducting this evaluation, the team employed new analysis tools that provided a much more detailed root cause analysis of the MU-2B problems than was previously possible.

Part of that evaluation was the identification of unsafe conditions that exist or could develop on the affected type design airplanes. One of these conditions is the potential for incorrect blade angle settings for the propellers. A survey of the operators, pilots, owners, and service center owners voiced a concern that 16-degree and 12-degree flight idle blade angles called out in Type Certificate Data Sheet A10SW, Note #3, could have caused confusion in blade angle settings for both propellers.

What is the potential impact if FAA took no action? This condition, if not corrected, could lead to an asymmetric thrust situation in certain flight conditions, which could result in airplane controllability problems.

Relevant Service Information

Is there service information that applies to this subject? We have reviewed Mitsubishi Aircraft International, Inc., Service Bulletin No. SB016/61-001, dated March 18, 1980.

What are the provisions of this service information? The service information describes procedures for the change of the flight idle blade angle.

Since Japan is the State of Design for the affected airplanes on one of the two type certificates, did the Japan Civil Airworthiness Board (JCAB) take any action? The MU-2B series airplane was initially certificated in 1965 and again in 1976 under two separate type certificates that consist of basically the same type design. Japan is the State of Design for TC No. A2PC, and the United States is the State of Design for TC No. A10SW. The models on the respective type certificates are as follows (where models are duplicated, specific serial numbers are specified in the individual TCs):

Type certificate	Models
A10SW	MU-2B-25, MU-2B-26, MU-2B-26A, MU-2B-35, MU-2B-36, MU-2B-36A, MU-2B-40, and MU-2B-60.
A2PC	MU-2B, MU-2B-10, MU-2B-15, MU-2B-20, MU-2B-25, MU-2B-26, MU-2B-30, MU-2B-35, and MU-2B-36.

Only certain models from Type certificate A10SW are affected by this proposed AD. Therefore, the JCAB did not issue any AD action because, as State of Design, they had no affected airplanes.

FAA's Determination and Requirements of the Proposed AD

Why have we determined AD action is necessary and what would this proposed AD require? We are proposing this AD to address an unsafe condition that we determined is likely to exist or develop on other products of this same type design. The proposed AD would require you to change the flight idle blade angle. The proposed AD would require you to use the service information described previously to perform these actions.

Costs of Compliance

How many airplanes would this proposed AD impact? We estimate that this proposed AD affects 148 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 do this proposed modification to change the flight idle blade angle:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
6 work hours × $65 = $390	Not Applicable	$390	$57,720

Are there other actions that FAA is issuing that would present a cost impact on the MU-2B series airplane fleet? This is one of several actions that FAA is evaluating for unsafe conditions on the MU-2B airplanes. To date, we have proposed the following action:

Docket	Unsafe condition	Date NPRM published	Cost impact
FAA-2006-23578	Wing attach barrel nuts, bolts, and retainers for cracks, corrosion, and fractures	January 25, 2006 (71 FR 4072)	$65 per airplane for the inspection and $1,195 per airplane if all 8 barrel nuts needed replacement. Total airplane cost is $1,260 per airplane. If all 397 airplanes needed all 8 barrel nuts replaced, the total cost on U.S. operators for this proposed action would be $500,220.

Total proposed cost impact to date (including this NPRM) for the affected airplanes is $1,650 per airplane. This does not account for the following:

• The cost of any repairs or replacements based upon the results of inspections by the proposed actions; and
• The loss of revenue due to the airplane being down for work associated with any proposed AD action.

The total cost to date on all U.S. operators to date (including this NPRM) would be $557,940. This is based on the presumption that all 357 airplanes would need all 8 barrel nuts replaced per Docket No. FAA-2006-23578.

Authority for This Rulemaking

What authority does FAA have for issuing this rulemaking action? 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

Would this proposed AD impact various entities? 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. See the ADDRESSES section for a location to examine the regulatory evaluation.

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 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 adding the following new airworthiness directive:

Mitsubishi Heavy Industries: Docket No. FAA-2006-23644; Directorate Identifier 2006-CE-03-AD.

When Is the Last Date I Can Submit Comments on This Proposed AD?

(a) The Federal Aviation Administration (FAA) must receive comments on this proposed airworthiness directive (AD) action by March 17, 2006.

What Other ADs Are Affected by This Action?

(b) None.

What Airplanes Are Affected by This AD?

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

Model	Serial Nos.
(1) MU-2B-26A and MU-2B-40	321SA, 348SA, 350SA through 419SA, 421SA, 422SA, and 423SA.
(2) MU-2B-36A and MU-2B-60	661SA, 697SA through 747SA, 749SA through 757SA, and 759SA through 773SA.

What Is the Unsafe Condition Presented in This AD?

(d) This AD results from a recent safety evaluation that used a data-driven approach to analyze the design, operation, and maintenance of the MU-2B series airplanes in order to determine their safety and define what steps, if any, are necessary for their safe operation. Part of that evaluation was the identification of unsafe conditions that exist or could develop on the affected type design airplanes. The actions specified in this AD are intended to prevent confusion in blade angle settings. This unsafe condition, if not corrected, could lead to an asymmetric thrust situation in certain flight conditions, which could result in airplane controllability problems.

What Must I Do To Address This Problem?

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

Actions	Compliance	Procedures
Change the flight idle blade angle	Within the next 100 hours time-in-service (TIS)	Follow Mitsubishi Aircraft International, Inc. Service Bulletin No. SB016/61-001, dated March 18, 1980.

May I Request an Alternative Method of Compliance?

(f) The Manager, Fort Worth Airplane Certification Office (ACO), FAA, has the authority to approve alternative methods of compliance for this AD, if requested using the procedures found in 14 CFR 39.19.

(g) For information on any already approved alternative methods of compliance or for information pertaining to this AD, contact Rao Edupuganti, Aerospace Engineer, Fort Worth ACO, ASW-150, Rotorcraft Directorate, FAA, 2601 Meacham Boulevard, Fort Worth, Texas 76137-4298; telephone: [phone]; facsimile: 817-222-5960.

May I Get Copies of the Documents Referenced in This AD?

(h) To get copies of the documents referenced in this AD, contact Mitsubishi Heavy Industries, Ltd., 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-2006-23644; Directorate Identifier 2006-CE-03-AD.

Issued in Kansas City, Missouri, on February 3, 2006.

John R. Colomy,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.