Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is revising an existing airworthiness directive (AD) for certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. That AD currently requires repetitive inspections of the left and right engine throttle control gearboxes for wear, and corrective action if necessary. This AD limits the applicability of the existing AD, extends the compliance time for the initial inspection, and clarifies the reporting requirement. This AD is prompted by numerous failures of the engine throttle control gearbox, some of which resulted in an in-flight engine shutdown. We are issuing this AD to prevent excessive wear of the gearboxes and subsequent movement or jamming of the engine throttle; movement of the throttle towards the idle position brings it close to the fuel shut-off position, which could result in an in-flight engine shutdown.

DATES:

Effective July 9, 2004.

The incorporation by reference of Bombardier Service Bulletin 601R-76-019, Revision “A,” dated February 19, 2004, listed in the AD, is approved by the Director of the Federal Register as of July 9, 2004.

On March 25, 2004 (69 FR 11293, March 10, 2004), the Director of the Federal Register approved the incorporation by reference of Bombardier Service Bulletin 601R-76-019, dated August 21, 2003.

We must receive any comments on this AD by August 23, 2004.

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: (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.

You can get the service information identified in this AD from Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada. You may examine this information 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.

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.

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.

Examining the Dockets

You may 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 (800) 647-5227) 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:

James Delisio, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, Westbury, New York 11581; telephone (516) 228-7321; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

On February 25, 2004, we issued AD 2004-05-12, amendment 39-13507 (69 FR 11293, March 10, 2004). That AD applies to all Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. That AD requires repetitive inspections of the left and right engine throttle control gearboxes for wear, and corrective action if necessary. That AD was prompted by numerous failures of the engine throttle control gearbox, some of which resulted in an in-flight engine shutdown. The actions specified in that AD are intended to prevent excessive wear of the gearboxes and subsequent movement or jamming of the engine throttle; movement of the throttle towards the idle position brings it close to the fuel shut-off position, which could result in an in-flight engine shutdown.

New Relevant Service Information

Since we issued that AD, Bombardier has issued Service Bulletin 601R-76-019, Revision ‘A,’ dated February 19, 2004. (AD 2004-05-12 refers to the original issue of that service bulletin, dated August 21, 2003, as the appropriate source of service information to use when you do the required actions.) The procedures in Revision ‘A’ of the service bulletin are similar to those in the original issue. Therefore, we have revised paragraphs (a), (b), and (c) of this AD to allow you to use Revision ‘A’ of the service bulletin when you do the required actions. We have determined that accomplishment of the actions specified in the service information will adequately address the unsafe condition.

Comments

We provided the public the opportunity to submit comments in response to AD 2004-05-12. We have considered the comments that were submitted.

Request To Limit Applicability

One commenter states that the difference in applicability between AD 2004-05-12 and Canadian airworthiness directive CF-2004-01, dated January 21, 2004, which is the Canadian airworthiness directive that parallels AD 2004-05-12, is unnecessary and could confuse operators. (This difference is noted in the “Differences Among Canadian Airworthiness Directive, Bombardier Service Bulletin, and This AD” section of AD 2004-05-12.) The commenter would like the applicability of our AD to include only serial numbers 7003 through 7067 inclusive, and 7069 through 7999 inclusive. The commenter explains that one of the airplanes included in the applicability of the U.S. AD but not the Canadian airworthiness directive has been destroyed and another is a prototype used for testing, is not eligible for a standard Certificate of Airworthiness, and can't be sold to a commercial operator.

We agree that making the applicability statement of our AD the same as that of the Canadian airworthiness directive will eliminate confusion and will not omit any affected airplanes. We have limited the applicability of this AD to airplanes having serial numbers 7003 through 7067 inclusive, and 7069 through 7999 inclusive.

Request To Extend Compliance Time

Several commenters request that we revise or eliminate the calendar time portion of the compliance time in paragraph (a) of AD 2004-05-12 (which was specified as “Within 1,000 flight hours or 90 days after the effective date of this AD, whichever is first”). The commenters assert that this compliance time will not significantly improve safety and, for airplanes with a low use rate, may force operators to do the required actions much earlier than the actions need to be done to ensure safety. One commenter states that many operators use their airplanes at a rate of only about 50 flight hours per week, and the 90-day compliance time would force operators to modify components that still have adequate wear margin. Two commenters note that tying the compliance time to calendar time is not appropriate because gearbox wear is not time dependent, only flight-cycle dependent. One commenter also points out that the 90-day compliance time may not allow operators sufficient time to plan for corrective actions and to procure parts, so airplanes could be grounded due to lack of parts.

We agree. After further review of the use rates of the affected airplanes, we find that an acceptable compliance time is the later of 1,000 flight hours or 90 days after the effective date of the AD. We determine that extending the compliance time in this way will ensure that worn gearboxes are removed from the airplane before the wear extends beyond specified limits, and won't adversely affect safety. We revised paragraph (a) of this AD accordingly.

Request To Include Subject Part Numbers

One commenter requests that AD 2004-05-12 include the part numbers of the current gearbox, as listed in the referenced Bombardier service bulletin. The commenter notes that this would prevent the inspection requirements of the AD from being incorrectly applied to gearboxes of a new design certificated in the future.

We agree. If we specify the subject part numbers in this AD, you will not have to inspect new gearbox designs (with new part numbers) certificated in the future, and we will not have to revise this AD or approve an Alternative Method of Compliance for this AD. We added the subject part numbers to paragraph (a) of this AD.

Request To Clarify Reporting Requirement

One commenter requests that we revise the reporting requirement specified in paragraph (c) of AD 2004-05-12 to clarify what information should be reported to the manufacturer. The commenter notes that paragraph (c) specifies to send a report of gearbox wear to the manufacturer, but also refers to specific paragraphs in the Accomplishment Instructions of the service bulletin that instruct operators to report incorrect bolt and screw torque values to the manufacturer. The commenter states that it isn't clear what data the AD requires to be sent to the manufacturer.

We agree to clarify the reporting requirement. Our intent is for you to report data on gearbox wear, not necessarily the incorrect torque values mentioned in the service bulletin. The reference to the service bulletin was intended to indicate only the fax number to which you should send the report. For clarification, we revised paragraph (c) of this AD to remove the references to the service bulletin, and to specify what information you must report and where you must send the report. We have also revised paragraph (c) of this AD to add certain boilerplate regulatory language that was omitted from AD 2004-05-12.

Request for Credit for Inspections Done Previously

One commenter requests that we provide credit for inspections already done on affected airplanes. The commenter states that it inspected several of its airplanes before we issued the AD. The commenter states that not giving credit for previous inspections would require it to inspect the airplane again, possibly at a much shorter interval than the 1,000-flight-hour repeat interval required by the existing AD.

We find that no change to the AD is necessary to meet the intent of the commenter's request. We always give credit for work done previously, by means of the phrase in the compliance section of the AD that states, “Required * * * unless accomplished previously.” If you've already done the initial inspection, you must do the next inspection within the repetitive interval required by the AD. We have not changed the final rule regarding this issue.

Request To Correct Terminology

Two commenters note that a certain term used in the statement of the unsafe condition throughout AD 2004-05-12 is incorrect. Where the unsafe condition refers to “fuel shut-off switch,” the correct term is “fuel shut-off position.” This is the term used in the referenced service information and the airplane maintenance manuals. We agree with the commenters and have corrected the term in this AD.

Request To Revise Note 1

One commenter requests that we revise Note 1 of AD 2004-05-12 to refer to Trans Digm, Inc., AeroControlex Group, Service Bulletin 2100140-007-76-04, dated July 22, 2003. (Note 2 of AD 2004-05-12 refers to that service bulletin as an additional source of service information.) The commenter is concerned that Note 1 does not adequately define the necessary inspection. The commenter states that the inspection procedures in the Trans Digm, Inc., AeroControlex Group, service bulletin are more thorough.

We do not agree that any change is necessary. Paragraph (a) of AD 2004-05-12 specifies “doing all the actions per Part A, paragraphs A., B., and C.(1) through C.(4), of the Accomplishment Instructions of Bombardier Service Bulletin 601R-76-019 * * *.” The inspection definition in Note 1 of the AD is a standard inspection definition that we use in all AD actions that specify a detailed inspection. Note 1 does not relieve the requirement, specified in paragraph (a) of this AD, to accomplish the inspection per the Accomplishment Instructions of the service bulletin. We made no change related to this comment.

Request To Revise Paragraph (b)

One commenter requests that we revise paragraph (b) of AD 2004-05-12 to delete paragraphs (b)(1), (b)(2), and (b)(3). The commenter is concerned that repeating the verbiage of the service bulletin may confuse operators. The commenter notes that the procedures are fully described in the service bulletin, so there is no need to repeat the procedure in our AD.

We do not agree. We acknowledge that paragraph (b) could have been written at a higher level with less detail. However, the information specified in those paragraphs is technically accurate, and paragraph (b) requires that the applicable actions in paragraphs (b)(1), (b)(2), and (b)(3) must be done per the Accomplishment Instructions of the referenced service bulletin. We have made no change related to this comment.

FAA's Determination and Requirements of This AD

These airplane models are manufactured in Canada and are 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 Civil Aviation (TCCA), which is Canada's airworthiness authority, 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, this AD is being issued to revise AD 2004-05-12. We are revising that AD to continue to require repetitive inspections of the left and right engine throttle control gearboxes for wear, and corrective action if necessary. This AD limits the applicability of the existing AD, extends the compliance time for the initial inspection, and clarifies the reporting requirement. This AD requires you to use the Bombardier service information described previously to perform these actions, except as discussed under “Difference Between the AD and Service Information.” This AD also requires that operators report the inspection results to Bombardier.

Difference Between the AD and Service Information

Although the Bombardier service information recommends returning discrepant gearboxes to the parts manufacturer, this AD does not contain that requirement.

Interim Action

We consider this AD to be interim action. The reports that you are required to submit will enable the manufacturer to obtain better insight into the nature, cause, and extent of the wear of the engine throttle control gearbox, and eventually to develop final action to address the unsafe condition. Once final action has been identified, we may consider further rulemaking.

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 written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2004-18231; Directorate Identifier 2004-NM-94-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 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 with you. You can get more information about plain language at http://www/faa.gov/language and http://www.plainlanguage.gov .

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 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.

2. The FAA amends § 39.13 by removing Amendment 39-13507 ( 69 FR 11293, March 10, 2004) and adding the following new AD:

2004-05-12 R1 Bombardier, Inc. (Formerly Canadair): Amendment 39-13683. Docket No. FAA-2004-18231; Directorate Identifier 2004-NM-94-AD.

Applicability: Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, certificated in any category, serial numbers 7003 through 7067 inclusive, and 7069 through 7999 inclusive.

Compliance: Required as indicated, unless accomplished previously.

To prevent excessive wear of the gearboxes and subsequent movement or jamming of the engine throttle (movement of the throttle towards the idle position brings it close to the fuel shut-off position, which could result in an in-flight engine shutdown), accomplish the following:

Repetitive Inspections

(a) Within 1,000 flight hours or 90 days after March 25, 2004 (the effective date AD 2004-05-12, amendment 39-13507), whichever is later: Do a detailed inspection for wear of the left and right engine throttle control gearboxes having part number (P/N) 2100140-005 or 2100140-007 by doing all the actions per Part A, paragraphs A., B., and C.(1) through C.(4), of the Accomplishment Instructions of Bombardier Service Bulletin 601R-76-019, dated August 21, 2003; or Revision “A,” dated February 19, 2004. If the wear value is the same as that specified in Part A, paragraph B.(8), of the Accomplishment Instructions of the service bulletin, repeat the inspection thereafter at intervals not to exceed 1,000 flight hours.

Note 1:

For the purposes of this AD, a detailed inspection is: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”

Corrective Action

(b) If the wear value found during any inspection required by paragraph (a) of this AD is not the same as that specified Part A, paragraph B.(8), of the Accomplishment Instructions of Bombardier Service Bulletin 601R-76-019, dated August 21, 2003; or Revision “A,” dated February 19, 2004: Do the applicable actions required by paragraph (b)(1), (b)(2), or (b)(3) of this AD, at the time specified, per the Accomplishment Instructions of the service bulletin. Repeat the inspection required by paragraph (a) of this AD thereafter at intervals not to exceed 1,000 flight hours.

(1) If the wear value on one or both of the gearboxes is the same as that specified in Part A, paragraph B.(5), of the Accomplishment Instructions of the service bulletin: Before further flight, replace the affected gearbox with a new or serviceable gearbox, by doing all the actions per Part B, paragraphs D. through F.(7), of the Accomplishment Instructions of the service bulletin.

(2) If the wear value on both the left and right gearboxes is the same as that specified in Part A, paragraph B.(6), of the Accomplishment Instructions of the service bulletin: Before further flight, replace the gearbox having the higher wear value with a new or serviceable gearbox, by doing all the actions per Part B, paragraphs D. through F.(7), of the Accomplishment Instructions of the service bulletin. Within 1,000 flight hours after doing the replacement, replace the other gearbox.

(3) If the wear value on only one gearbox is the same as that specified in Part A, paragraph B.(7), and the wear value on the other gearbox is the same as that specified in Part A, paragraph B.(8), of the Accomplishment Instructions of the service bulletin: Within 1,000 flight hours after the inspection, replace the gearbox with the wear value that is the same as that specified in Part A, paragraph B.(7), with a new or serviceable gearbox. Do the replacement by doing all the actions per Part B, paragraphs D. through F.(7), of the Accomplishment Instructions of the service bulletin.

Additional Service Information

Note 2:

Bombardier Service Bulletin 601R-76-019, dated August 21, 2003; and Revision “A,” dated February 19, 2004; reference Trans Digm, Inc., AeroControlex Group, Service Bulletin 2100140-007-76-04, dated July 22, 2003, as an additional source of service information for accomplishment of the inspections and replacement.

Reporting Requirement

(c) Within 10 days after doing the inspection required by paragraph (a) of this AD, or within 10 days after March 25, 2004, whichever is later: Submit a report of gearbox wear to Bombardier Aerospace, In-Service Engineering (Engine Group); fax (514) 855-7708. The report must include the airplane serial number, the number of flight hours on the airplane, and the number of flight hours on each gearbox (if different than the number of flight hours on the airplane). Under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements contained in this AD and has assigned OMB Control Number 2120-0056.

Alternative Methods of Compliance

(d) The Manager, New York Aircraft Certification Office, FAA, has the authority to approve alternative methods of compliance (AMOCs) for this AD, if requested using the procedures found in 14 CFR 39.19.

Material Incorporated by Reference

(e) You must use Bombardier Service Bulletin 601R-76-019, dated August 21, 2003; or Bombardier Service Bulletin 601R-76-019, Revision “A,” dated February 19, 2004; to perform the actions that are required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of Bombardier Service Bulletin 601R-76-019, Revision “A,” dated February 19, 2004; in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.

(2) The Director of the Federal Register previously approved the incorporation by reference of Bombardier Service Bulletin 601R-76-019, dated August 21, 2003; on March 25, 2004 (69 FR 11293, March 10, 2004).

(3) You can get copies of the documents from Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada. 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 (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Note 3:

The subject of this AD is addressed in Canadian airworthiness directive CF-2004-01, dated January 21, 2004.

Effective Date

(f) This amendment becomes effective on July 9, 2004.