AD 97-11-08 ACTIVE

This amendment adopts a new airworthiness directive (AD), applicable to all Bombardier Model CL-415 series airplanes. This action requires revising the Airplane Flight Manual (AFM) to modify the limitation that prohibits positioning the power levers below the flight idle stop during flight, and to provide a statement of the consequences of positioning the power levers below the flight idle stop during flight. This amendment is prompted by incidents and accidents involving airplanes equipped with turboprop engines in which the propeller ground beta range was used improperly during flight. The actions specified in this AD are intended to prevent loss of airplane controllability, or engine overspeed and consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight.

Final rule; request for comments

97-11-08 BOMBARDIER, INC. (Formerly Canadair): Amendment 39-10037. Docket 97-NM-31-AD.
Applicability: All Model CL-415 series airplanes, certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been 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 (b) 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 loss of airplane controllability, or engine overspeed and consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight, accomplish the following:

(a) Within 30 days after the effective date of this AD, revise the Limitations Section of the FAA-approved Airplane Flight Manual (AFM) to include the following statements. This action may be accomplished by inserting a copy of this AD into the AFM.

"Positioning of power levers below the flight idle stop while the airplane is in flight is prohibited. Such positioning may lead to loss of airplane control or may result in an overspeed condition and consequent loss of engine power."

(b) 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 theirrequests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO.

(c) 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.

(d) This amendment becomes effective on June 6, 1997.

In recent years, the FAA has received reports of 14 incidents and/or accidents involving intentional or inadvertent operation of the propellers in the beta range during flight on airplanes equipped with turboprop engines. (For the purposes of this amendment, Beta is defined as the range of propeller operation intended for use during taxi, ground idle, or reverse operations as controlled by the power lever settings aft of the flight idle stop.)

Five of the fourteen in-flight beta occurrences were classified as accidents. In each of these five cases, operation of the propellers in the beta range occurred during flight. Operation of the propellers in the beta range during flight, if not prevented, could result in loss of airplane controllability, or engine overspeed with consequent loss of engine power.

Communication between the FAA and the public during a meeting held on June 11-12, 1996, in Seattle, Washington, revealed a lack of consistency of the information on in-flight beta operation contained in the FAA-approved Airplane Flight Manual (AFM) for airplanes that are not certificated for in-flight operation with the power levers below the flight idle stop. (Airplanes that are certificated for this type of operation are not affected by the above-referenced conditions.)

FAA's Determinations
After examining the circumstances and reviewing all available information related to the incidents and accidents described previously. The FAA finds that the Limitations Section of the AFM s for certain airplanes must be revised to prohibit positioning the power levers below the flight idle stop while the airplane is in flight, and to provide a statement of the consequences of positioning the power levers below the flight idle stop. The FAA has determined that the affected airplanes include those that are equipped with turboprop engines and that are not certificated for in-flight operation with the power levers below the flight idlestop. Since Bombardier Model CL-415 series airplanes meet these criteria, the FAA finds that the AFM for these airplanes must be revised to include the limitation and statement of consequences described previously.

U.S. Type Certification of the Airplane
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. 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.

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, this AD is being issued to prevent loss of airplane controllability, or engine overspeed and consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight.

This AD requires revising the Limitations Section of the AFM to modify the limitation that prohibits positioning the power levers below the flight idle stop while the airplane is in flight, and to add a statement of the consequences of positioning the power levers below the flight idle stop while the airplane is in flight.

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

Cost Impact
None of the Model CL-415 series airplanes affected by this action are on the U.S. Register. All airplanes included in the applicability of this rule currently are operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, the FAA considers that this rule is necessary to ensure that the unsafe condition is addressed in the event that any of these subject airplanes are imported and placed on the U.S. Register in the future.

Should an affected airplane be imported and placed on the U.S. Register in the future, it would require approximately 1 work hour to accomplish the required actions, at an average labor charge of $60 per work hour. Based on these figures, the cost impact of this AD would be $60 per airplane.

Determination of Rule's Effective Date
Since this AD action does not affect any airplane that is currently on the U.S. register, it has no adverse economic impact and imposes no additional burden on any person. Therefore, prior notice and public procedures hereon are unnecessary and the amendment may be made effective in less than 30 days after publication in the Federal Register.

Comments Invited
Although this action is in the form of a final rule and was not preceded by notice and opportunity for public comment, comments are invited on this rule. Interested persons are invitedto comment on this 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 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.

Comments are specifically invited on the overall regulatory, 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 thesubstance 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 97-NM-31-AD. The postcard will be date stamped and returned to the commenter.

Regulatory Impact
The regulations adopted herein will 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 final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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, 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 followingnew airworthiness directive:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 97-NM-31-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.
The information concerning this amendment may be obtained from or 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, 10 Fifth Street, Third Floor, Valley Stream, New York.

Peter LeVoci, Flight Test Pilot, Systems and Flight Test Branch, ANE-172, FAA, Engine and Propeller Directorate, New York Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New York 11581; telephone (516) 256-7514; fax (516) 568-2716.