E6-4924. Airworthiness Directives; Boeing Model 727 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 certain Boeing Model 727 airplanes. This proposed AD would require repetitive measurements of the freeplay of the left and right outboard aileron balance tabs and of the upper and lower rudder tabs, and related investigative/corrective actions if necessary. This proposed AD also would require repetitive lubrication of the hinge bearings and rod end bearings of the aileron balance tabs. This proposed AD results from reports of freeplay-induced vibration of the outboard aileron balance tab and rudder tab. We are proposing this AD to prevent excessive vibration of the airframe during flight, which could result in divergent flutter and loss of control of the airplane.

DATES:

We must receive comments on this proposed AD by May 22, 2006.

ADDRESSES:

Use one of the following addresses to submit comments 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.
• 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 Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for the service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT:

Dennis Stremick, Aerospace Engineer, Airframe Branch, ANM-120S, Seattle Aircraft Certification Office, FAA, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number “FAA-2006-24271; Directorate Identifier 2006-NM-006-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 AD. Using the search function of that Web site, anyone can find and read the comments in 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 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 Docket

You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone [phone]) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them.

Discussion

We have received several reports of freeplay-induced vibration of the outboard aileron balance tab and a couple of reports of freeplay-induced vibration of the rudder tab on Boeing Model 727 airplanes. Excessive corrosion and wear of components and/or interfaces allows excessive freeplay movement of the control surfaces and can cause excessive vibration of the airframe during flight. The point of transition from vibration to divergent flutter is unknown. When divergent flutter occurs, the amplitude of each cycle or oscillation is larger than the last one and the surface can reach its structural limits. This condition, if not corrected, could result in loss of control of the airplane.

Relevant Service Information

We have reviewed Boeing Special Attention Service Bulletin 727-27-0234, dated November 10, 2005. The service bulletin describes procedures for repetitive measurements of the freeplay of the left and right outboard aileron balance tabs and of the upper and lower rudder tabs. If the freeplay exceeds certain specified limits, the service bulletin describes procedures for doing applicable related investigative and corrective actions. These related investigative and corrective actions include doing a general visual inspection for wear of the affected bearings, bolts, and bushings; and repairing or replacing the affected part. The corrective actions also include repeating the freeplay measurement and any related investigative and corrective actions until the maximum freeplay is within acceptable limits. For the repetitive measurements of the freeplay, the service bulletin specifies an initial compliance time of 18 months and repetitive intervals of 8,000 flight hours or 24 months, whichever occurs first. The service bulletin also describes procedures for repetitive lubrication of the hinge bearings and rod end bearings of the aileron balance tabs. For the repetitive lubrications, the service bulletin specifies an initial compliance time of 9 months and repetitive intervals of 3,200 flight hours and 6,000 flight hours, depending on if grease was used. Accomplishing the actions specified in the service bulletin is intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. For this reason, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

There are about 944 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

 Estimated Costs

Action	Work hours	Average labor rate per hour	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
Freeplay measurement	8	$80	$640, per lubrication cycle	539	$344,960, per measurement cycle.
Lubrication	4	80	$320, per measurement cycle	539	$172,480, per lubrication cycle.

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. 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 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 Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2006-24271; Directorate Identifier 2006-NM-006-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by May 22, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 727, 727C, 727-100, 727-100C, 727-200, and 727-200F series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 727-27-0234, dated November 10, 2005.

Unsafe Condition

(d) This AD results from reports of freeplay-induced vibration of the outboard aileron balance tab and rudder tab. We are issuing this AD to prevent excessive vibration of the airframe during flight, which could result in divergent flutter and loss of control of the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Compliance Times

(f) Except as provided by paragraph (h) of this AD, at the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 727-27-0234, dated November 10, 2005, do the actions specified in paragraph (g) of this AD. Where the service bulletin specifies a compliance time “from the initial release of this service bulletin,” this AD requires compliance within the applicable compliance time after the effective date of this AD.

Freeplay Measurement, Related Investigative and Corrective Actions, and Lubrication

(g) At the applicable times specified in paragraph (f) of this AD, do the actions specified in paragraphs (g)(1) and (g)(2) of this AD in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 727-27-0234, dated November 10, 2005.

(1) Measure the freeplay of the left and right outboard aileron balance tabs and of the upper and lower rudder tabs, and do applicable related investigative and corrective actions if necessary.

(2) Lubricate the hinge bearings and rod end bearings of the aileron balance tabs.

Concurrent Repetitive Cycles

(h) If a freeplay measurement required by paragraph (g)(1) of this AD and a lubrication cycle required by paragraph (g)(2) of this AD are due at the same time or will be done during the same maintenance visit, the freeplay measurement and applicable related investigative and corrective actions must be done before the lubrication.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

Issued in Renton, Washington, on March 29, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.