04-15515. Airworthiness Directives; Bombardier Model DHC-8-311 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Bombardier Model DHC-8-311 airplanes. This proposed AD would require reviewing the airplane maintenance records to determine if you did the most recent bonding integrity inspection according to a certain revision of the Maintenance Program Support Manual (PSM), and doing related investigative and corrective actions if necessary. This proposed AD is prompted by the discovery that a certain revision of the PSM omits several fuselage skin panels from a list of skin panels that must be inspected. We are proposing this AD to prevent disbonding of the subject skin panels, which could reduce the load-carrying capacity of the skin panels and result in reduced structural integrity of the airplane.

DATES:

We must receive comments on this proposed AD by August 9, 2004.

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.
• By 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.

You may examine the contents of this AD docket on the Internet at http://dms.dot.gov, or 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.

FOR FURTHER INFORMATION CONTACT:

Jon Hjelm, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, Westbury, New York 11590; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Docket Management System (DMS)

The FAA has implemented new procedures for maintaining AD dockets electronically. As of May 17, 2004, new AD actions are posted on DMS and assigned a docket number. We track each action and assign a corresponding directorate identifier. The DMS AD docket number is in the form “Docket No. FAA-2004-99999.” The Transport Airplane Directorate identifier is in the form “Directorate Identifier 2004-NM-999-AD.” Each DMS AD docket also lists the directorate identifier (“Old Docket Number”) as a cross-reference for searching purposes.

Comments Invited

We invite you to submit any written relevant data, views, or arguments regarding this proposed AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2004-18563; Directorate Identifier 2002-NM-98-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 submitted 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 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 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.

We are reviewing the writing style we currently use in regulatory documents. We are interested in your comments on whether the style of this document is clear, and your suggestions to improve the clarity of our communications that affect you. You can get more information about plain language at http://www.faa.gov/​language and http://www.plainlanguage.gov.

Examining the Docket

You may examine the AD docket 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.

Discussion

Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, notified us that an unsafe condition may exist on certain Bombardier Model DHC-8-311 airplanes. TCCA advises that several fuselage skin panels were inadvertently omitted from the list of those to be inspected in Maintenance Program Support Manual (PSM) 1-83-7A, Revision 6, dated January 30, 2001. Though PSM 1-83-7A, Revision 7, dated August 15, 2001, has been issued, the omission of the subject fuselage skin panels from Revision 6 could result in the subject fuselage skin panels remaining uninspected until the next bonding integrity inspection. The repetitive interval for those inspections is 3 years. Disbonding of the uninspected skin panels could occur in the interval between inspections. This condition, if not corrected, could reduce the load-carrying capacity of the skin panels and result in reduced structural integrity of the airplane.

TCCA issued Canadian airworthiness directive CF-2002-08, dated January 25, 2002, to ensure the continued airworthiness of these airplanes in Canada.

FAA's Determination and Requirements of the Proposed AD

This airplane model is manufactured in Canada and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, TCCA has kept the FAA informed of the situation described above. We have examined TCCA's findings, evaluated all pertinent information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States. Therefore, we are proposing this AD, which would require you to review airplane maintenance records to determine if you did the most recent bonding integrity inspection according to PSM 1-83-7A, Revision 6. If you did the most recent bonding integrity inspection according to PSM 1-83-7A, Revision 6 (or if you can't conclusively determine what revision of the PSM you used), the proposed AD would require you to do a resonance frequency inspection for disbonding of the skin panels and repair if necessary. You must do the inspection for disbonding according to a method that either we or TCCA (or its delegated agent) approve. We approve PSM 1-83-7A, Revision 7, as one method for accomplishing the inspection for disbonding. You must do any necessary repairs according to a method that we or TCCA (or its delegated agent) approve. This proposed AD would also prohibit you from using PSM 1-83-7A, Revision 6, for inspections for disbonding of fuselage skin panels performed after the effective date of the AD.

Costs of Compliance

This proposed AD would affect about 8 airplanes of U.S. registry. The proposed records review would take about 1 work hour per airplane, at an average labor rate of $65 per work hour. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $520, or $65 per airplane.

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

Bombardier, Inc. (Formerly de Havilland, Inc.): Docket No. FAA-2004-18563; Directorate Identifier 2002-NM-98-AD.

Comments Due Date

(a) The Federal Aviation Administration must receive comments on this AD action by August 9, 2004.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Model DHC-8-311 airplanes, serial numbers 202 through 298 inclusive, certificated in any category.

Unsafe Condition

(d) This AD was prompted by the discovery that a certain revision of the Maintenance Program Support Manual (PSM) omits several fuselage skin panels from a list of skin panels that must be inspected. We are issuing this AD to prevent disbonding of the subject skin panels, which could reduce the load-carrying capacity of the skin panels and result in reduced structural integrity 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.

Review of Maintenance Records

(f) Within 14 days after the effective date of this AD, review the airplane maintenance records or maintenance logbook to determine if the most recent bonding integrity inspection of the fuselage skin panels was done according to Bombardier Maintenance Program Support Manual (PSM) 1-83-7A, Revision 6, dated January 30, 2001.

(1) If it can conclusively be determined that the most recent bonding integrity inspection of the fuselage skin panels was done according to PSM 1-83-7A, Revision 5, dated April 30, 1999; or Revision 7, dated August 15, 2001: This AD requires no further action.

(2) If the most recent bonding integrity inspection of the fuselage skin panels was done according to PSM 1-83-7A, Revision 6, dated January 30, 2001, or if it cannot be conclusively determined what revision of PSM 1-83-7A was used: At the applicable compliance time specified in paragraph (f)(2)(i) or (f)(2)(ii) of this AD, do a resonance frequency inspection of the fuselage skin panels listed in Table 1 of this AD, according to a method approved by either the Manager, New York Aircraft Certification Office (ACO), FAA; or Transport Canada Civil Aviation (TCCA) (or its delegated agent). PSM 1-83-7A, Revision 7, dated August 15, 2001, is one approved method.

(i) If no disbonding was found during any previous bonding integrity inspection: Within 1,000 flight hours or 6 months after the effective date of this AD, whichever is first.

(ii) If any disbonding was found during any previous bonding integrity inspection: Within 6 weeks after the effective date of this AD.

Table 1.—Fuselage Skin Panels

Engineering drawing	Skin panel description	PSM 1-83-7A figure/sheet
85330204	Skin, Right Side, Bottom	Figure 4/(Sheet 2).
85330201	Skin, Right Side	Figure 4/(Sheet 5).
85330180	Skin, Right Side, Top	Figure 4/(Sheet 6).
85330181	Skin, Left Side, Top	Figure 4/(Sheet 7).
85330106	Skin, Left Side, Bottom	Figure 4/(Sheet 14).
85330105	Skin, Left Side	Figure 4/(Sheet 15).
85330101	Skin, Left Side, Bottom	Figure 4/(Sheet 16).
85330033	Skin, Bottom	Figure 4/(Sheet 17).
85330032	Skin, Right Side, Lower	Figure 4/(Sheet 18).
85330032	Skin, Right Side, Lower with Service Door	Figure 4/(Sheet 19).
85330031	Skin, Left Side, Lower	Figure 4/(Sheet 20).
85332750	Skin, Bottom, Center	Figure 4/(Sheet 25).
85332750	Skin, Bottom, Center	Figure 4/(Sheet 26).

Repair

(g) If any disbonding is found during the resonance frequency inspection required by paragraph (f) of this AD: Before further flight, repair per a method approved by the Manager, New York ACO; or TCCA (or its delegated agent).

Limitation on Future Inspections

(h) As of the effective date of this AD, no person may use PSM 1-83-7A, Revision 6, dated January 30, 2001, to inspect for disbonding of fuselage skin panels on any airplane having any serial number 202 through 298 inclusive.

Alternative Methods of Compliance (AMOCs)

(i) The Manager, New York ACO, has the authority to approve AMOCs for this AD, if an AMOC is requested in accordance with the procedures found in 14 CFR 39.19.

Related Information

(j) Canadian airworthiness directive CF-2002-08, dated January 25, 2002, also addresses the subject of this AD.

Issued in Renton, Washington, on June 30, 2004.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.