AD 97-2519

[Federal Register Volume 62, Number 22 (Monday, February 3, 1997)] [Proposed Rules] [Pages 4941-4944] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 97-2519]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-108-AD] RIN 2120-AA64

Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional Jet Series 100) Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Bombardier Model CL-600-2B19 (Regional Jet Series 100) series airplanes. That AD currently requires revisions to the Airplane Flight Manual (AFM) to advise the flight crew of the need to perform daily checks to verify proper operation of the elevator control system, and to restrict altitude and airspeed operations under certain conditions. That AD also requires removal of all elevator flutter dampers. That AD was prompted by reports that the installation of certain shear pins may jam or restrict movement of the elevator. The actions specified by that AD are intended to prevent such jamming or restricting movement of the elevator and the resultant adverse effect on the controllability of the airplane. This new proposed action would add inspections of certain airplanes to detect deformation or discrepancies of the flutter damper hinge fittings and lug of the horizontal stabilizer, the elevator hinge/damper fitting, and the shear pin lugs; and require replacement of discrepant parts with serviceable parts. This proposed action also would require installation of new elevator flutter dampers, and replacement of shear pins and shear links with new, improved pins and links.

DATES: Comments must be received by March 14, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 96-NM-108-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays. The service information referenced in the proposed rule may be obtained from Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller Directorate, New York Aircraft Certification Office, 181 South Franklin Avenue, Valley Stream, New York.

FOR FURTHER INFORMATION CONTACT: Franco Pieri, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, New York Aircraft Certification Office, FAA, Engine and Propeller Directorate, 10 Fifth Street, Third Floor, Valley Stream, New York 11581;

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telephone (516) 256-7526; fax (516) 568-2716.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 96-NM-108-AD.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 96-NM-108-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On November 17, 1994, the FAA issued AD 94-24-02, amendment 39-9075 (59 FR 60888, November 29, 1994), applicable to certain Bombardier Model CL-600-2B19 series airplanes. That AD requires: 1. the removal of all elevator flutter dampers; and 2. a revision to the FAA-Approved Airplane Flight Manual (AFM) to advise the flight crew of the need to perform daily checks to verify proper operation of the elevator control system. In addition, that AD retained the requirements from AD 94-01-09, amendment 39-8791 (59 FR 1471, January 11, 1994), to revise the AFM to restrict altitude and airspeed operations under conditions of single or double hydraulic system failure. That AD was prompted by reports that the installation of certain shear pins may jam or restrict movement of the elevator. The requirements of that AD are intended to prevent failure of the lugs and/or pins. Such failure could increase the likelihood of jamming or restricting movement of the elevator, which could result in an adverse effect on the controllability of the airplane.

Actions Since Issuance of Previous Rule

Since the issuance of that AD, the manufacturer has issued Canadair Regional Jet Service Bulletin S.B. 601R-27-040, Revision `B,' dated September 11, 1995. For certain airplanes, this service bulletin describes procedures for a visual inspection to detect deformation or discrepancies of the flutter damper hinge fitting and lug of the horizontal stabilizer, and of the elevator hinge/damper fitting and shear pin lugs; a fluorescent penetrant inspection and a dimensional inspection to detect any deformation or discrepancy of the shear pin lugs; and replacement of discrepant parts with serviceable parts. For these and other airplanes, this service bulletin also describes procedures for installation of a new elevator flutter damper having a reduced load capacity, and for replacement of the shear pins and shear links with new, improved shear pins and links. Accomplishment of the actions described in that service bulletin will improve the integrity of the elevator damping system and increase the service fatigue life of the flutter damper. The manufacturer also has issued two general revisions to the AFM for these airplanes: Revision 32, dated March 30, 1995, which advises the flight crew of the need to perform daily checks to verify proper operation of the elevator control system. Revision 34, dated June 12, 1995, which specifies certain altitude and airspeed restrictions to prevent flight control undamped vibration during hydraulic system failure. Transport Canada Aviation, which is the airworthiness authority for Canada, classified the service bulletin and AFM revisions as mandatory, and issued Canadian airworthiness directive CF-94-21R1, dated November 3, 1995, in order to assure the continued airworthiness of these airplanes in Canada.

FAA's Conclusions

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, Transport Canada Aviation has kept the FAA informed of the situation described above. The FAA has examined the findings of Transport Canada Aviation, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would supersede AD 94-24-02. It would continue to require the removal of the originally installed elevator dampers. It also would continue to require revisions to the Limitations Section of the FAA-approved AFM to restrict altitude and airspeed operations under conditions of single or double hydraulic system failure, and to advise the flight crew of the need to perform daily checks to verify proper operation of the elevator control system. As stated in this proposal, these revisions could be accomplished by inserting a copy of this AD or the new AFM revisions, described previously, in the AFM. For certain airplanes, this new proposed AD would require inspections to detect deformation or discrepancies of the flutter damper hinge fitting and lug of the horizontal stabilizer, the elevator hinge/damper fitting, and the shear pin lugs; and replacement of discrepant parts with serviceable parts. For those and other airplanes, the proposed AD also would require installation of new elevator flutter dampers, and replacement of shear pins and shear links with new, improved pins and links. These actions would be required to be accomplished in accordance with the service bulletin described previously.

Interim Action

This is considered to be interim action until final action is identified, at which time the FAA may consider further rulemaking.

Difference Between the Proposed AD and the Service Information

Operators should note that, the effectivity listing of AFM Revision 32, dated March 30, 1995 (which advises the flight crew of the need to perform

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daily checks of the elevator control system), indicates that it applies only to those airplanes having serial numbers 7002 through 7054 and on which Canadair Regional Jet Service Bulletin S.B. 601R-27-040 (Part A) has not been accomplished. However, this proposed AD would require that the AFM revision be accomplished for those airplanes, regardless of whether or not the procedures specified in the Canadair service bulletin have been accomplished. The FAA has been specifically advised by Transport Canada Aviation that the accomplishment of the service bulletin procedures should not be considered as a ``terminating action'' for the AFM revision. Further, the parallel Canadian airworthiness directive continues to require this revision of the AFM. In light of this, the FAA has determined that, until final action addressing the unsafe condition is developed, the revision of the AFM must be required in addition to the procedures specified in the Canadair Regional Jet service bulletin.

Cost Impact

There are approximately 21 Bombardier Model CL-600-2B19 (Regional Jet Series 100) series airplanes of U.S. registry that would be affected by this proposed AD. The actions that are currently required by AD 94-24-02, and retained in this proposal, take approximately 6 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact on U.S. operators of the actions currently required is estimated to be $7,560, or $360 per airplane. The FAA estimates that all affected U.S. operators have previously accomplished these requirements, therefore, the future cost impact of these requirements is minimal. For airplanes that would require the inspections that are proposed in this AD, it would take approximately 26 work hours per airplane to accomplish them, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed inspections on U.S. operators is estimated to be $1,560 per airplane. The installations that are proposed in this AD would take approximately 12 work hours per airplane to accomplish them, at an average labor rate of $60 per work hour. Required parts would be provided by the manufacturer at no cost to the operator. Based on these figures, the cost impact on U.S. operators of the proposed installations is estimated to be $15,120, or $720 per airplane. The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the current or proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

The regulations proposed herein would not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this 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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by removing amendment 39-9075 (59 FR 60888, November 29, 1994), and by adding a new airworthiness directive (AD), to read as follows:

Bombardier, Inc. (Formerly Canadair): Docket 96-NM-108-AD. Supersedes AD 94-24-02, Amendment 39-9075.

Applicability: Model CL-600-2B19 (Regional Jet Series 100) series airplanes having serial numbers 7003 through 7054 inclusive, certificated in any category.

Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously. To prevent failure of lugs and/or pins, which may increase the likelihood of jamming or restricting movement of the elevator and the resultant adverse effect on controllability of the airplane, accomplish the following:

Restatement of Requirements of AD 94-01-09

(a) Within 30 days after January 26, 1994 (the effective date of AD 94-01-09, amendment 39-8791), revise the Limitations Section of the FAA-approved Airplane Flight Manual (AFM) to include the following restrictions of altitude and airspeed operations under conditions of single or double hydraulic system failure; and advise the flight crew of these revised limits. Revision of the AFM may be accomplished by inserting a copy of this AD or AFM Revision 34, dated June 12, 1995, in the AFM.

------------------------------------------------------------------------ Altitude limit (maximum) Airspeed limit (maximum) ------------------------------------------------------------------------ Single Hydraulic System Failure ------------------------------------------------------------------------ 31,000 feet.............................. 0.55 Mach (199 KIAS). 30,000 feet.............................. 0.55 Mach (204 KIAS). 28,000 feet.............................. 0.55 Mach (213 KIAS). 26,00 feet............................... 0.55 Mach (222 KIAS). 24,000 feet.............................. 0.55 Mach (232 KIAS). 22,000 feet.............................. 0.55 Mach (241 KIAS). 20,000 feet and below.................... 252 KIAS. ------------------------------------------------------------------------ Double Hydraulic System Failure ------------------------------------------------------------------------ 10,000 feet.............................. 200 KIAS. ------------------------------------------------------------------------

Note 2: The restrictions described in the AFM Temporary Revision (TR) RJ/30, dated December 16, 1993; meet the requirements of this paragraph. Therefore, inserting a copy of TR RJ/30 in lieu of this AD in the AFM is considered an acceptable means of compliance with this paragraph.

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Restatement of Requirements of AD 94-24-02

(b) Within 7 days after December 14, 1994 (the effective date of AD 94-24-02, amendment 39-9075), accomplish the requirements of paragraph (b)(1) and (b)(2) of this AD: (1) Until the requirements of paragraph (c)(2) of this AD are accomplished, remove the elevator dampers in accordance with Canadair Regional Jet Alert Service Bulletin S.B. A601R-27-041, dated October 28, 1994. (2) Revise the Limitations Section of the FAA-approved AFM to include the following, which advises the flight crew of daily checks to verify proper operation of the elevator control system. Revision of the AFM may be accomplished by inserting a copy of this AD or AFM Revision 32, dated March 30, 1995, in the AFM.

Note 3: The daily check described in the AFM Temporary Revision (TR)RJ/40, dated October 28, 1994, meets the requirements of this paragraph. Therefore, inserting a copy of TR RJ/40 into the AFM in lieu of this AD is considered an acceptable means of compliance with this paragraph.

``Elevator, Before Engine Start (First Flight of Day)

(1) Elevator................... Check.......... Travel range (to approximately 1/2 travel) using each hydraulic system in turn, with the other hydraulic systems depressurized.''

New Requirements of this AD

(c) Within 12 months after the effective date of this AD, perform the requirements of paragraphs (c)(1) and (c)(2) of this AD, as applicable, in accordance with Canadair Regional Jet Service Bulletin S.B. 601R-27-040, Revision `B,' dated September 11, 1995. (1) For airplanes having serial numbers 7003 through 7049, inclusive: Perform the inspections specified in paragraphs (c)(1)(i), (c)(1)(ii), and (c)(1)(iii) of this AD in accordance with Section 2.B., Part A, of the service bulletin. (i) Remove the shear pins and shear links of the flutter dampers and perform a visual inspection to detect any deformation or discrepancy of the flutter damper hinge fitting and lug of the horizontal stabilizer. Prior to further flight, replace any deformed or discrepant part with a serviceable part in accordance with the service bulletin. (ii) Perform a visual inspection to detect any deformation or discrepancy of the elevator hinge/damper fitting and shear pin lugs. Prior to further flight, replace any discrepant part with a serviceable part in accordance with the service bulletin. (iii) Perform a fluorescent penetrant inspection and a dimensional inspection to detect any deformation or discrepancy of the shear pin lugs. If any deformation or discrepancy is found on the lugs, prior to further flight, replace the elevator with a new or serviceable elevator in accordance with the service bulletin. (2) For airplanes having serial numbers 7003 through 7054, inclusive: Install new shear pins [part number (P/N) 601R24063-953] and new elevator flutter dampers (P/N 601R75142-7) in accordance with Section 2.B., Part B, of the service bulletin: (d) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, New York Aircraft Certification Office (ACO), FAA, Engine and Propeller Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO.

Note 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO.

(e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Issued in Renton, Washington, on January 27, 1997. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 97-2519 Filed 1-31-97; 8:45 am] BILLING CODE 4910-13-U