We have received a report indicating that a Bombardier Model CL-600-1A11 (CL-600) airplane experienced a rejected take-off and subsequently overran the runway. The nose landing gear collapsed, and the forward fuselage was damaged as a result of the incident. The flightcrew reported that, when they attempted to take off, the control column would not move aft beyond the neutral position. Investigation revealed that the microphone jack assembly installed on the co-pilot's control column was bent downward, which restricted the aft movement of the control column. This condition, if not corrected, could result in loss of control of the airplane.
The microphone jack assembly on the affected airplane was installed incidental to Supplemental Type Certificate (STC) SA4900SW. Therefore, we find that all Bombardier Model CL-600-1A11 (CL-600), CL-600-2A12 (CL-601), and CL-600-2B16 (CL-601-3A, CL-601-3R, and CL-604) airplanes modified by that STC may be subject to thesame unsafe condition.
Relevant Service Information
Raytheon has issued Service Bulletin SB 23-3727, dated May 2005. The service bulletin describes procedures for modifying the microphone jack assembly, and performing related investigative actions and corrective actions if necessary. The related investigative actions include performing a general visual inspection of the cover of the pilot's and co-pilot's control columns for cracking around the existing fastener holes for the microphone bracket assembly; a Non-Destructive Test (NDT) of the microphone jack assembly for any damage, including cracks; and a measurement of the distance between existing fastener holes and the location of the new fastener holes. (The service bulletin specifies various alternatives for performing the NDT including dye- penetrant, ultrasonic, and eddy current methods.) The service bulletin specifies to contact Raytheon if any cracking or damage is found, or if the minimum distance between existing andnew fastener holes is below a certain limit. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.
Bombardier Advisory Wire AW600-00-2247, Revision 2, dated March 24, 2005, also addresses the subject of this AD. Section 3.0, Action, of the Advisory Wire recommends a repetitive inspection to "verify the security of the installation of the [microphone jack] receptacle." The intent of this inspection is identical to that of the repetitive visual checks specified in the airplane flight manual (AFM) revision required by paragraph (f) of this AD.
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 Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. We have evaluated all pertinent information, and determined that we need to issue an AD for products of this type design that are modified by STC SA4900SW and certificated for operation in the United States.
Therefore, we are issuing this AD to prevent a damaged microphone jack assembly from interfering with movement of the control column, which could result in loss of control of the airplane. This AD requires revising the AFM to require repetitive visual checks of the microphone jack assemblies on both control columns to detect damage that may interfere with movement of the control column. We have determined that the checks specified in the AFM revision must be performed by the flightcrew because of the possibility that damage to the microphone jack assembly may occur between the time an inspection is performed by maintenance personnel and the time the flightcrew enters the flight deck to prepare for the flight. (For example, a member of the flightcrew may inadvertently step on the microphone jack assembly, causing it to bend.) We have determined thatit is possible for the flightcrew to perform the visual checks because the checks do not require tools, precision measuring equipment, training, or pilot logbook endorsements, or the use of or reference to technical data that are not contained in the body of the AD.
This AD also requires accomplishing the actions specified in the service information described previously, except as discussed under "Differences Between the AD and Service Information," after which the AFM revision may be removed from the AFM.
Differences Between the AD and Service Information
Although the Raytheon service bulletin specifies that operators may contact the manufacturer for disposition of certain repair conditions, this proposed AD would require operators to repair those conditions according to a method approved by the FAA.
The Raytheon service bulletin recommends that the modification of the microphone jack assembly be accomplished before the next flight or within 15 days from receipt ofthe service bulletin, whichever is first. This AD specifies a compliance time for the modification of 15 flight hours or 15 days after the effective date of the AD, whichever is first. In developing an appropriate compliance time for this AD, we considered the manufacturer's recommendation, the degree of urgency associated with the subject unsafe condition, and the average utilization of the affected fleet. We also considered the recommendation for repetitive inspections in Bombardier Advisory Wire AW600-00-2247, Revision 2. (These repetitive inspections are similar to the repetitive visual checks specified in the AFM revision required by this AD.) In light of all of these factors, we find that, for the modification, a compliance time of 15 flight hours or 15 days, whichever is earlier, represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety, provided that the microphone jack assembly is checked for damage before every flight. We find that this compliance time should provide an opportunity for affected operators to accomplish the modification without unnecessarily grounding airplanes. This difference has been coordinated with Raytheon.
Although the Accomplishment Instructions of the referenced service bulletin describe procedures for reporting accomplishment of the service bulletin, this AD does not require that action. We do not need this information from operators.
Clarification of Service Bulletin Note
The Raytheon service bulletin includes a note in the Accomplishment Instructions to inform operators to contact Raytheon "should any difficulty be encountered" in accomplishing the service bulletin. We have included Note 3 in this proposed AD to clarify that any deviation from the instructions provided in the service bulletin must be approved as an alternative method of compliance under paragraph (i) of this proposed AD.
FAA's Determination of the Effective Date
An unsafe conditionexists 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 relevant written data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include "Docket No. FAA-2005-21315; Directorate Identifier 2005-NM-090-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 can review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.
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." Underthat 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.
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 FR11034, 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 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 airworthiness directive (AD):