AD 2008-06-10

We are adopting a new airworthiness directive (AD) for certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This AD requires repetitive detailed inspections for cracking of the left side and right side frame and reinforcement angles at fuselage station (FS) 640 between stringer 9 and stringer 12, and corrective actions if necessary. This AD also provides an optional terminating action for the repetitive inspections. This AD results from reports that cracks have been discovered on the frame and reinforcement angles at FS 640. We are issuing this AD to detect and correct cracking of the frame, which could lead to failure of the fuselage structure and possible loss of the airplane.

Final rule.

2008-06-10 Bombardier, Inc. (Formerly Canadair): Amendment 39-15422. Docket No. FAA-2007-29257; Directorate Identifier 2007-NM-144-AD.

Effective Date

(a) This airworthiness directive (AD) is effective April 16, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, certificated in any category; as identified in Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006.

Unsafe Condition

(d) This AD results from reports that cracks have been discovered on the frame and reinforcement angles at fuselage station (FS) 640. Failure of this frame could degrade the structural integrity of the airplane. We are issuing this AD to detect and correct cracking of the frame, which could lead to failure of the fuselage structure and possible loss of the airplane.

Compliance

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

Detailed Inspection

(f) Before the accumulation of 8,600 total flight cycles, or within 1,100 flight cycles after the effective date of this AD, whichever occurs later: Perform a detailed inspection to detect cracking of the left side and right side frames and reinforcement angles at FS640 between stringer 9 and stringer 12, in accordance with Part A of the Accomplishment Instructions of Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006.

Note 1: For the purposes of this AD, a detailed inspection is: "An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.''

Repetitive Inspection and Corrective Action

(g) If no crack is found during the inspection required by paragraph (f) of this AD: Repeat the detailed inspection thereafter at intervals not to exceed 1,100 flight cycles, until the frame modification described in paragraph (h)(2) of this AD or the optional terminating modification described in paragraph (i) of this AD has been done.
(h) If any crack is found during the inspection required by paragraph (g) of this AD: Before further flight, repair the crack in accordance with paragraph (h)(1), (h)(2), or (h)(3) of this AD, as applicable.
(1) For any crack found in the frame at the stringer 9 cut-out only, repair in accordance with Part A of the Accomplishment Instructions of Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006.
(2) For any crack found in the frame reinforcement doubler only, do the actions described in paragraphs (h)(2)(i) and (h)(2)(ii) of this AD.
(i) Do the frame modification (including related investigative and corrective actions) described in Part C of the Accomplishment Instructions of Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006; except where the service bulletin specifies to contact the manufacturer for repair instructions, repair the crack using a method approved by either the Manager, New York Aircraft Certification Office (ACO), FAA; or Transport Canada Civil Aviation (TCCA) (or its delegated agent).
(ii) Within 12,000 flight cycles after doing the modification required by paragraph (h)(2)(i) of this AD, do the detailed inspection required by paragraph (f) of this AD, then repeat the detailed inspection thereafter at intervals not to exceed 1,100 flight cycles.
(3) For any crack found in areas of the inspection zone described in paragraph (f) of this AD other than those areas described in paragraphs (h)(1) and (h)(2) of this AD: Repair the crack using a method approved by either the Manager, New York ACO, FAA; or TCCA (orits delegated agent).

Optional Terminating Action

(i) Reinforcement of any engine support beam in accordance with the Accomplishment Instructions of the service information described in paragraph (i)(1) or (i)(2) of this AD, as applicable, ends all repetitive inspections required by this AD for that support beam.
(1) For all airplanes: If the reinforcement is done before the effective date of this AD, Bombardier Alert Service Bulletin A601R- 53-059, Revision E, dated March 21, 2005; or Revision F, dated April 21, 2006; may be used. After the effective date of this AD, only Bombardier Alert Service Bulletin A601R-53-059, Revision F, may be used.
(2) For airplanes identified in Bombardier Service Bulletin 601R-53-065, Revision B, dated November 2, 2007: If the reinforcement is done before the effective date of this AD, Bombardier Service Bulletin 601R-53-065, Revision A, dated August 24, 2005, or Revision B, may be used. After the effective date of this AD, only Bombardier Service Bulletin 601R-53-065, Revision B, may be used.

No Reporting Requirement

(j) Although Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006, specifies to submit certain information to the manufacturer, this AD does not include that requirement.

Alternative Methods of Compliance (AMOCs)

(k)(1) The Manager, New York 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) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

Related Information

(l) Canadian airworthiness directive CF-2003-12, dated May 7, 2003, also addresses the subject of this AD.

Material Incorporated byReference

(m) You must use Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006, including Appendix B, Revision C, dated June 25, 2003, to do the actions required by this AD, unless the AD specifies otherwise. If you accomplish the optional actions specified by this AD, you must use Bombardier Alert Service Bulletin A601R-53-059, Revision F, dated April 21, 2006, excluding Appendix A, dated June 14, 2001; or Bombardier Service Bulletin 601R-53-065, Revision B, dated November 2, 2007; as applicable; to perform those actions, unless the AD specifies otherwise. Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006, includes the following effective pages:

Page Number
Revision Level Shown on Page
Date Shown on Page
1 - 44
E
December 7, 2006

Appendix B
B1 - B8
C
June 25, 2003

(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part51.
(2) For service information identified in this AD, contact Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada.

(3) You may review copies of the service information incorporated by reference at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_ regulations/ibr_locations.html.

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. That NPRM was published in the Federal Register on September 20, 2007 (72 FR 53704). That NPRM proposed to require repetitive detailed inspections for cracking of the left side and right side frame and reinforcement angles at fuselage station (FS) 640 between stringer 9 and stringer 12, and corrective actions if necessary.

Comments

We gave the public the opportunity to participate in developing this AD. We have considered the comments received.

Request To Address Possible Terminating Modification

Air Wisconsin requests that we consider including a possible terminating modification in the NPRM. Air Wisconsin states that the NPRM does not recognize other options that can be taken to modify FS640. Air Wisconsin continues that, in fact, a certain option is significantly better, providing a higher level of safety than the modification in Part C of Bombardier Service Bulletin 601R-53-061, Revision E, dated December 7, 2006, including Appendix B, Revision C, dated June 25, 2003 (cited as the appropriate source of service information for doing the proposed actions described in the NPRM), which is an interim modification requiring further inspections. Air Wisconsin continues that Transport Canada Civil Aviation (TCCA) issued an alternate means of compliance (AMOC) indicating that the inspections of Service Bulletin 601R-53-061 can be terminated by doing applicable actions described in Bombardier Alert Service Bulletin A601R-53-059, Revision E, dated March 21, 2005 (or later); or Bombardier Service Bulletin 601R-53-065, Revision A, dated August 24, 2005 (or later). Air Wisconsin states it has already modified 23 airplanes using Service Bulletin A601R-53-059, Revision E; or Bombardier Alert Service Bulletin A601R-53-059, Revision F, dated April 21, 2006; and intends to modify all its other affected airplanes within the next one to two years. Air Wisconsin asserts that any AD issued against Service Bulletin 601R-53- 061 should specify that doing the applicable actions described in Service Bulletin A601R-53-059, Revision E or F; or Service Bulletin 601R-53-065, Revision A; is acceptable for terminating the repetitive inspections of Service Bulletin 601R-53-061.

We agree with this request. In the NPRM, we stated that we considered the proposed AD to be interim action, and that we might consider further rulemaking if final action was later identified. We have determined that Air Wisconsin's request addresses appropriate final action, as described in the following service information. We have reviewed Bombardier Alert Service Bulletin A601R-53-059, Revision E, dated March 21, 2005, and Revision F, dated April 21, 2006; and Bombardier Service Bulletin 601R-53-065, Revision A, datedAugust 24, 2005, and Revision B, dated November 2, 2007. The service bulletins describe procedures for reinforcing the engine support beams that are acceptable for terminating the repetitive inspections described by Service Bulletin 601R-53-061, Revision E. We have determined that any reinforcement of the engine support beam done in accordance with Part A, B, or C, as applicable, of Alert Service Bulletin A601R 53-059, Revision E or F; or in accordance with Service Bulletin 601R-53-065, Revision A or B; is acceptable as optional terminating action for the repetitive inspections required by this AD. Therefore, we have added this service information to the AD; deleted existing paragraph (f) of the NPRM; revised subsequent paragraphs (g), (h), and (i) of this AD, and re-identified them as paragraphs (f), (g), and (h); relocated and reidentified paragraph (j) of the NPRM as new paragraph (h)(2)(ii) of this AD; added new paragraph (i) of this AD to describe the optional terminating action;and reidentified subsequent paragraphs (k), (l), and (m) of the NPRM, as paragraphs (j), (k), and (l) of this AD.

Request for Clarification of Special Flight Permits

Comair requests that we clarify paragraph (i) of the NPRM (paragraph (h) of this AD) regarding relocation of airplanes to service facilities after the discovery of cracking. Comair is concerned that the requirement to repair the crack before further flight forbids moving the airplane to a repair facility to accomplish the repair. Comair cites earlier ADs that included a provision for obtaining special flight permits to move airplanes to repair facilities in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199). Comair requests that such a statement be inserted into the NPRM.
We do not agree with this request. On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs our ADs. Part 39 now includes material that relates to altered products, special flight permits, and AMOCs. Because this material now appears in part 39, an AD refers to special flight permits only when relocation flights are limited or not permitted. In that case, in accordance with 14 CFR 21.197 and 21.199 as described by the commenter, operators may apply for a special flight permit to move affected airplanes. However, special flights are neither limited nor prohibited by this AD; therefore, "before further flight'' in this AD applies to any flight other than the flight taken to relocate the airplane to the repair facility. We have not changed the AD in this regard.

Conclusion

We reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We determined that these changes will not increase the economic burden on any operator or increase the scope of the AD.

Costs of Compliance

This AD affects about 739 airplanes of U.S. registry. The required inspection takes about 2 work hours per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the AD for U.S. operators is $118,240, or $160 per airplane, per inspection 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 ofthat authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

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 this AD:
(1) Is not a "significant regulatory action'' under Executive Order 12866,
(2) Is not a "significant rule'' under 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.
You can find our regulatory evaluation and the estimated costs of compliance in the AD Docket.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.

Sec. 39.13 [Amended]

2. The FAA amends Sec. 39.13 by adding the following new AD: