Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, recently notified the FAA that an unsafe condition may exist on certain Model CL-600-2C10 (Regional Jet Series 700 & 701) series airplanes. TCCA advises that fuel nozzles installed on the auxiliary power unit (APU) on these airplanes may crack and leak fuel into the APU compartment. According to the APU manufacturer, the cracks develop during APU start. Cracks are not readily detectable when the APU is installed in the airplane. An APU fuel nozzle can crack due to fatigue, and the resulting leak could cause fuel to spray throughout the APU compartment and be drawn out of the APU exhaust duct. This condition, if not corrected, could result in a fire or explosion in the APU compartment during flight.
Explanation of Relevant Service Information
Bombardier has issued Temporary Revision (TR) RJ 700/28-2, dated November 5, 2002, to the Canadair Regional Jet Series 700Airplane Flight Manual. The TR advises the flightcrew to limit use of the APU to ground operation only, except for those in-flight emergencies described in the AFM when use of the APU is specified. TCCA has approved the TR for these airplanes in Canada. By approving the TR, TCCA also mandates its immediate incorporation into the AFM; therefore, TCCA did not issue a Canadian airworthiness directive to specifically mandate incorporation of the TR.
The FAA has reviewed Honeywell Alert Service Bulletin RE220-49- A7714, dated November 4, 2002, which describes procedures for replacing all APU fuel nozzles with new fuel nozzles (including installing new seals and washers; reidentifying the APU; and torqueing the bolts and fuel manifold connector within specified ranges). The service bulletin specifically cautions against intermixing fuel nozzle part numbers on an APU or interchanging the subject ("-2") fuel nozzles on a modified APU.
U.S. Type Certification of the Airplane
Thisairplane 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 the FAA informed of the situation described above. The FAA has 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. TCCA fully agrees with the requirements and compliance time specified in this AD.
Explanation of Requirements of 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, this AD is being issued to prevent fuel from being sprayed throughout the APU compartment and drawn out of the APU exhaust duct due to a cracked APU fuel nozzle, which couldresult in a fire or explosion in the APU compartment during flight. This AD requires revising the AFM to advise the flightcrew to limit use of the APU to ground operation only, except for those in-flight emergencies described in the AFM when use of the APU is specified.
This AD also provides for optional terminating action for the actions required by this AD. In accord with TCCA's findings, the FAA has determined that the operating limitations imposed by this AD can remain in place in lieu of accomplishment of a terminating action. In making this determination, the FAA considers that, in this case, implementing the AFM limitations will adequately ensure long-term continued operational safety before the unsafe condition could present a safety risk to the airplane.
Difference Between AD and Service Bulletin
Although the service bulletin recommends that operators send all removed fuel nozzles to Honeywell, this AD does not require operators to do so.
Interim ActionThis is considered to be interim action. The FAA may consider requiring eventual replacement of the APU fuel nozzles, which would allow operators to remove the AFM limitation required by this AD. However, the planned compliance time for APU fuel nozzle replacement, if required, would be long enough to practicably provide notice and opportunity for public comment before the final rule is issued.
Determination of Rule's Effective Date
Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this ruleby 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 under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.
Submit comments using the following format:
Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
For each issue, state what specific change to the AD is being requested.
Include justification (e.g., reasons or data) for each request.
Comments are specifically invited on the overallregulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the 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 that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2002-NM-269-AD." The postcard will be date stamped and returned to the commenter.
Regulatory Impact
The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.
The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration 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.
39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: