Federal Aviation Administration (FAA), DOT.
Notice of proposed rulemaking (NPRM).
The FAA proposes to adopt a new airworthiness directive (AD) for all Bombardier Model DHC–7 series airplanes. This proposed AD would require implementing a corrosion prevention and control program (CPCP) either by accomplishing specific tasks or by revising the maintenance inspection program to include a CPCP. This proposed AD is prompted by the determination that, as airplanes age, they are more likely to exhibit indications of corrosion. We are proposing this AD to prevent structural failure of the airplane due to corrosion.
We must receive comments on this proposed AD by September 21, 2005.
Use one of the following addresses to submit comments on this proposed AD.
• DOT Docket Web site: Go to
• Government-wide rulemaking Web site: Go to
• Mail: Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, room PL–401, Washington, DC 20590.
• By fax: (202) 493–2251.
• 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 proposed AD, contact Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada.
Jon Hjelm, Aerospace Engineer, Airframe and Propulsion Branch, ANE–171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, suite 410, Westbury, New York 11590; telephone (516) 228–7323; fax (516) 794–5531.
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.
We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed under
We will post all comments we receive, without change, to
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
You can examine the AD docket on the Internet at
Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, notified us that an unsafe condition may exist on all Bombardier Model DHC–7 series airplanes. TCCA advises that, as airplanes age, they are more likely to exhibit indications of corrosion. Operators must implement a Corrosion Prevention and Control Program (CPCP) that identifies specific areas to be inspected to minimize and control deterioration of the airplane from corrosion. This condition, if not corrected, could result in structural failure of the airplane.
Bombardier has issued de Havilland Inc. Corrosion Prevention and Control Manual, DHC–7 (Dash 7), Product Support Manual (PSM) 1–7–5, dated May 13, 1997. (In this proposed AD, we refer to this publication as “the Manual.”)
The Introduction to the Manual defines three levels of corrosion:
• Level 1 corrosion:
1. Occurs between repetitive inspections, is local, and can be reworked within certain limits; or
2. Is local but exceeds allowable limits and is attributed to an event not typical of the usage of the other airplanes in the operator's fleet; or
3. Exceeds allowable limits but for which only light corrosion has been found in previous inspections.
• Level 2 corrosion:
1. Occurs between repetitive inspections and exceeds allowable limits, necessitating a repair or partial or complete replacement of a structural significant element; or
2. Occurs between repetitive inspections, is widespread, and requires rework approaching allowable limits.
• Level 3 corrosion is found during initial or repetitive inspections and is determined to be a potentially urgent unsafe condition necessitating expeditious action.
Following the Introduction, the Manual is divided into three basic parts:
• Part 1 refers to Part 1 of PSM 1–GEN–5, which contains general information on corrosion.
• Part 2 describes specific inspections for corrosion, including the effectivity, method, objective, and relevant PSM references for each inspection.
• Part 3 contains the Recommended Corrosion Inspection Program that applies to the subject airplanes, including corrosion task numbers, inspection thresholds, repetitive intervals, and necessary re-protection actions.
TCCA mandated the Manual and issued Canadian Airworthiness Directive CF–98–03, dated February 27, 1998, to ensure the continued airworthiness of these airplanes in Canada.
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 us 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 implementing a CPCP either by accomplishing specific tasks or by revising the maintenance inspection program to include a CPCP. The proposed AD would require you to use the Manual described previously to perform these actions. The proposed AD also would require you to report findings of Level 3 corrosion to us, and findings of Level 2 or 3 corrosion to the airplane manufacturer.
Canadian Airworthiness Directive CF–98–03 specifies the following compliance times for the initial inspection:
• For airplanes produced before January 1, 1986: Before December 31, 2000, or 20 years after the airplane's production date, whichever is later.
• For airplanes produced after December 31, 1985: Before December 31, 2005.
However, this proposed AD would require that you do the initial inspection within 12 months after the effective date of this AD. In developing an appropriate compliance time for this AD, we considered the compliance times specified in Canadian Airworthiness Directive CF–98–03, the manufacturer's recommendation, and the degree of urgency associated with the subject unsafe condition. We also considered the fact that the Manual (which is the appropriate source of service information referenced in this proposed AD) has been available to all operators of affected airplanes since May 1997. In light of all of these factors, we find that a 12-month compliance time represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety.
Also, Canadian airworthiness directive CF–98–03 specifies that findings of Level 2 and 3 corrosion must be reported to the airplane manufacturer, but CF–98–03 does not provide a compliance time for this action. This proposed AD specifies that these findings must be reported to the airplane manufacturer at the time specified in Section 5.0 of Part 3 of the Manual (
This proposed AD would affect about 26 airplanes of U.S. registry. The 148 specific inspections specified in the Manual would take about 48 work hours per airplane, per inspection cycle, 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 $81,120, or $3,120 per airplane, per inspection cycle.
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.
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
Air transportation, Aircraft, Aviation safety, Safety.
Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:
1. The authority citation for part 39 continues to read as follows:
49 U.S.C. 106(g), 40113, 44701.
2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):
(a) The Federal Aviation Administration must receive comments on this AD action by September 21, 2005.
(b) None.
(c) This AD applies to all Model DHC–7 series airplanes, certificated in any category.
(d) This AD was prompted by the determination that, as airplanes age, they are more likely to exhibit indications of corrosion. We are issuing this AD to prevent structural failure of the airplane due to corrosion.
(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.
(f) The term “the Manual,” as used in this AD, means the de Havilland Inc. Corrosion Prevention and Control Manual, DHC–7 (Dash 7), Product Support Manual (PSM) 1–7–5, dated May 13, 1997.
(g) Within 12 months after the effective date of this AD, perform each of the Corrosion Tasks, including re-protection actions, as applicable, specified in Part 3 of the Manual by accomplishing the basic tasks defined in Parts 2 and 3 of the Manual, in accordance with the procedures of the Manual.
(h) Except as provided by paragraph (i) of this AD, repeat each of the Corrosion Tasks, and re-protection actions, as applicable, specified in Part 3 of the Manual at intervals not to exceed 3 or 6 years, as specified in Part 3 of the Manual.
(i) After accomplishment of each initial Corrosion Task required by paragraph (g) of this AD, the FAA or Transport Canada Civil Aviation (TCCA) (or its delegated agent) may approve the incorporation into the operator's approved maintenance/inspection program of the Corrosion Prevention and Control Program (CPCP) specified in the Manual and this AD; or an equivalent program that is approved by the FAA or TCCA. In all cases, the initial Corrosion Task for each airplane area must be completed in accordance with the compliance time specified in paragraph (g) of this AD. Amendment of the operator's approved maintenance/inspection program to include an approved CPCP constitutes terminating action for the requirements of this AD.
(j) If any corrosion is found during accomplishment of any action required by paragraph (g) or (h) of this AD: Within 30 days after the finding, rework, repair, or replace any applicable part, as applicable, in accordance with Section 4.0 of Part 3 of the Manual.
(k) If any Level 3 corrosion, as defined in the Introduction of the Manual, is found, do paragraphs (k)(1) and (k)(2) of this AD.
(1) At the time specified in paragraph (k)(1)(i) or (k)(1)(ii) of this AD, whichever is later, submit a report of the findings to the Manager, New York Aircraft Certification Office (ACO), FAA, Engine and Propeller Directorate, 10 Fifth Street, Third Floor, Valley Stream, New York 11581; fax (516) 568–2716. The report must follow the format specified in Section 5.0 of Part 3 of the Manual, or be submitted using a Service Difficulty Report, as applicable. Under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501
(i) Within 3 days after the finding of Level 3 corrosion.
(ii) Within 10 days after the effective date of this AD.
(2) At the time specified in paragraph (k)(2)(i) or (k)(2)(ii) of this AD, whichever is later, submit a plan to the FAA to identify a schedule for accomplishing the applicable Corrosion Task on the remainder of the operator's fleet, or data substantiating that the Level 3 corrosion that was found is an isolated case. For the purposes of this paragraph, “FAA” means the Principal Maintenance Inspector (PMI) for operators that are assigned a PMI (
(i) Within 10 days after the finding of Level 3 corrosion.
(ii) Within 10 days after the effective date of this AD.
(l) If any Level 2 or 3 corrosion, as defined in the Introduction of the Manual, is found, at the applicable time specified in Section 5.0 of Part 3 of the Manual, or within 10 days after the effective date of this AD, whichever is later, report these findings to the manufacturer according to Section 5.0 of Part 3 of the Manual. Information collection requirements in this AD are approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501
(m) The Manager, New York Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19.
(n) Canadian airworthiness directive CF–98–03, dated February 27, 1998, also addresses the subject of this AD.