05-3268. Airworthiness Directives; Short Brothers Model SD3-60 Series Airplanes

AGENCY:

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

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for all Short Brothers Model SD3-60 series airplanes. This AD requires, for certain airplanes, repetitive inspections for cracking of the balance weight brackets of the elevator trim tabs, and replacement of any cracked bracket with a new or reworked bracket that conforms to the approved design standard. This AD also provides for an optional terminating action for the repetitive inspections. This AD is prompted by reports indicating that balance weight brackets have been found cracked on both the left and right elevator trim tabs. We are issuing this AD to prevent failure of the balance weight bracket for the elevator trim tab, which could cause loss of the balance weight. This could result in incorrect trim during takeoff and landing, and reduced controllability of the airplane.

DATES:

Effective March 14, 2005.

The incorporation by reference of a certain publication listed in the AD is approved by the Director of the Federal Register as of March 14, 2005.

We must receive comments on this AD by April 26, 2005.

ADDRESSES:

Use one of the following addresses to submit comments on this 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.

For service information identified in this AD, contact Short Brothers, Airworthiness & Engineering Quality, P.O. Box 241, Airport Road, Belfast BT3 9DZ, Northern Ireland. You can examine this information at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call [phone], or go to: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

You can examine the contents of this AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., room PL-401, on the plaza level of the Nassif Building, Washington, DC. This docket number is FAA-2005-20108; the directorate identifier for this docket is 2005-NM-006-AD.

Examining the Docket

You can 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 DMS receives them.

FOR FURTHER INFORMATION CONTACT:

Todd Thompson, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom, notified the FAA that an unsafe condition may exist on certain Short Brothers Model SD3-60 series airplanes. The CAA advises that balance weight brackets have been found cracked on both the left and right elevator trim tabs. Investigation revealed that the cracked brackets do not conform to the approved design standard. This nonconformity substantially reduces the expected fatigue life of the brackets, causing premature cracking and failure. This condition, if not corrected, could lead to loss of the balance weight. This could result in incorrect trim during takeoff and landing, and reduced controllability of the airplane.

Other Relevant Rulemaking

We have previously issued AD 2004-13-08, amendment 39-13690 (69 FR 38813, June 29, 2004). That AD applies to all Short Brothers Model SD3-60 series airplanes. That AD requires repetitive inspections for cracking of the welded joints of the balance weight brackets for the elevator trim tabs, and replacement of any cracked bracket with a new or serviceable bracket. That AD provides for eventual replacement of uncracked brackets as terminating action for the repetitive inspections.

AD 2004-13-08 refers to Short Brothers Service Bulletin SD360-55-20, dated June 26, 2003, as the applicable source of service information for the required actions. CAA notified us that operators may have installed the defective balance weight brackets that are the subject of this new AD while accomplishing Short Brothers Service Bulletin SD360-55-20.

Relevant Service Information

Short Brothers has issued Alert Service Bulletin SD360-55-A21, dated December 16, 2004. Short Brothers Alert Service Bulletin SD360-55-A21 describes procedures for performing repetitive dye penetrant inspections for cracking of the subject balance weight brackets. Short Brothers Alert Service Bulletin SD360-55-A21 also describes procedures for replacing balance weight brackets with new balance weight brackets that conform to the approved design standard, which is mandatory for any cracked balance weight bracket. Short Brothers Alert Service Bulletin SD360-55-A21 also describes procedures for refitting balance weights, covers, and trim tabs following any inspection or replacement. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition. The CAA mandated Short Brothers Alert Service Bulletin SD360-55-A21 and issued British emergency airworthiness directive G-2004-0032, dated December 30, 2004, to ensure the continued airworthiness of these airplanes in the United Kingdom.

FAA's Determination and Requirements of This AD

This airplane model is manufactured in the United Kingdom and is type certificated for operation in the United States under the provisions of § 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the CAA has kept the FAA informed of the situation described above. We have examined the CAA's findings, evaluated all pertinent information, and determined that we need to issue an AD for products of this type design that are certificated for operation in the United States.

Therefore, we are issuing this AD to prevent failure of the balance weight bracket for the elevator trim tab, which could cause loss of the balance weight. This could result in incorrect trim during takeoff and landing, and reduced controllability of the airplane. This AD requires, for certain airplanes, accomplishing the actions specified in the service information described previously, except as discussed under “Differences Between the AD and the Service Bulletin.”

Differences Between the AD and the Service Bulletin

The service bulletin specifies that operators may contact the manufacturer for disposition of certain conditions when refitting balance weights; for those conditions, this proposed AD would require operators to obtain further instructions from the FAA or the CAA (or its delegated agent).

The service bulletin specifies that subject parts must be returned to Short Brothers. This AD does not require that action.

Differences Between the AD and the British Emergency Airworthiness Directive

British emergency airworthiness directive G-2004-0032 requires replacing all subject balance weight brackets with new or reworked brackets that conform to the approved design standard. The British emergency airworthiness directive recommends that this replacement be accomplished before the accumulation of 1,750 flight hours since installation of the balance weight bracket. This AD provides for replacement of uncracked subject balance weight brackets as an option that, if accomplished, would constitute terminating action for the requirements of this AD.

British emergency airworthiness directive G-2004-0032 applies to Model SD3-60 series airplanes on which subject balance weight brackets were installed in accordance with the original issue of Short Brothers Service Bulletin SD360-55-20. This AD applies to all Model SD3-60 series airplanes. We have determined it is necessary to include all Model SD3-60 series airplanes in the applicability of this AD to ensure that no subject balance weight bracket will be installed in the future on any Model SD3-60 series airplane.

Interim Action

We consider this AD interim action. We are currently considering requiring the replacement of all subject balance weight brackets with new or reworked brackets that conform to the approved design standard, which would constitute terminating action for the repetitive inspections required by this AD. However, the planned compliance time for the replacement would allow enough time to provide notice and opportunity for prior public comment on the merits of the modification.

FAA's Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD; therefore, providing notice and opportunity for public comment before the AD is issued is impracticable, and good cause exists to make this AD effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements that affect flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any relevant written data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2005-20108; Directorate Identifier 2005-NM-006-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD. We will consider all comments received by the closing date and may amend the 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 AD. Using the search function of our docket 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 can review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.

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 AD will not have federalism implications under Executive Order 13132. This AD will 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 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 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
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 (AD):

2005-04-13 Short Brothers PLC: Amendment 39-13985. Docket No. FAA-2005-20108; Directorate Identifier 2005-NM-006-AD.

Effective Date

(a) This AD becomes effective March 14, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all Short Brothers Model SD3-60 series airplanes, certificated in any category.

Unsafe Condition

(d) This AD was prompted by reports indicating that balance weight brackets have been found cracked on both the left and right elevator trim tabs. The FAA is issuing this AD to prevent failure of the balance weight bracket for the elevator trim tab, which could cause loss of the balance weight. This could result in incorrect trim during takeoff and landing, and reduced controllability 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.

Service Bulletin Reference

(f) The following information applies to the service bulletin referenced in this AD:

(1) The term “service bulletin,” as used in this AD, means the Accomplishment Instructions of Short Brothers Alert Service Bulletin SD360-55-A21, dated December 16, 2004.

(2) Although the service bulletin specifies to return subject parts to the manufacturer, this AD does not include that requirement.

Repetitive Inspections

(g) For airplanes equipped with balance weight brackets of the elevator trim tabs having part number SD3-07-6011xA, and having a serial number beginning with “X3” or “X4': Prior to the accumulation of 250 flight hours since installation of the subject balance weight bracket of the elevator trim tab, or within 30 flight hours after the effective date of this AD, whichever is later, do a dye penetrant inspection for cracking of the balance weight brackets for the left and right elevator trim tabs, in accordance with the service bulletin.

(1) For a balance weight bracket on which no cracking is found: Do paragraph (i) of this AD, and repeat the inspection thereafter at intervals not to exceed 250 flight hours until paragraph (h) of this AD is accomplished.

(2) For a balance weight bracket on which any cracking is found: Before further flight, replace the bracket with a new or reworked balance weight bracket that conforms to the approved design standard in accordance with the service bulletin, and do paragraph (i) of this AD.

Optional Terminating Action

(h) For airplanes equipped with balance weight brackets of the elevator trim tabs having part number SD3-07-6011xA, and having a serial number beginning with “X3” or “X4': Replacement of any subject balance weight bracket with a new or reworked balance weight bracket that conforms to the approved design standard, in accordance with the service bulletin, constitutes terminating action for the repetitive inspections required by paragraph (g) of this AD for the replaced bracket.

Refitting

(i) For airplanes equipped with balance weight brackets of the elevator trim tabs having part number SD3-07-6011xA, and having a serial number beginning with X3 or X4: Before further flight following any inspection or replacement of a bracket in accordance with this AD: Refit the balance weights, covers, and trim tabs, in accordance with the service bulletin. Where the service bulletin specifies to contact the manufacturer for disposition of certain conditions while refitting, obtain further disposition instructions from the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate; or the Civil Aviation Authority (CAA) (or its delegated agent).

Parts Installation

(j) For all airplanes: As of the effective date of this AD, no person may install, on any airplane subject to this AD, a balance weight bracket having part number SD3-07-6011xA, and having a serial number beginning with “X3” or” X4,” unless the bracket is also marked “Rework batch number R-Bxxxxx” (where “xxxxx” is a number).

Alternative Methods of Compliance (AMOCs)

(k) The Manager, International Branch, ANM-116, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

Related Information

(l) British emergency airworthiness directive G-2004-0032, dated December 30, 2004, also addresses the subject of this AD.

Material Incorporated by Reference

(m) You must use Short Brothers Alert Service Bulletin SD360-55-A21, dated December 16, 2004, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approves the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. For copies of the service information, contact Short Brothers, Airworthiness & Engineering Quality, P.O. Box 241, Airport Road, Belfast BT3 9DZ, Northern Ireland. You can review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW, room PL-401, Nassif Building, Washington, DC; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call [phone], or go to http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Issued in Renton, Washington, on February 11, 2005.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.