AD 97-26-14 ACTIVE

This amendment adopts a new airworthiness directive (AD) that applies to all MAULE Models MX-7-420 and MXT-7-420 airplanes, and all Models M-7-235 and M-7-235A airplanes that are modified in accordance with Maule STC SA2661SO, which incorporates a certain gas turbine engine, certain amphibious floats, and certain propellers. This AD requires amending the Limitations Section of the airplane flight manual (AFM) to prohibit the positioning of the power levers below the flight idle stop while the airplane is in flight. This AFM amendment will include a statement of consequences if the limitation is not followed. This AD results from numerous incidents and five documented accidents involving airplanes equipped with turboprop engines where the propeller beta was improperly utilized during flight. The actions specified by this AD are intended to prevent loss of airplane control or engine overspeed with consequent loss of engine power caused by the power levers being positioned belowthe flight idle stop while the airplane is in flight.

Final rule.

97-26-14 Maule: Amendment 39-10257; Docket No. 97-CE-40-AD.

Applicability: The following airplane models, certificated in any category:

--Models MXT-7-420 and MX-7-420 airplanes, all serial numbers; and --Models M-7-235 and M-7-235A airplanes, all serial numbers, that are modified in accordance with Maule Supplemental Type Certificate (STC) SA2661SO.

Note 1: Maule STC SA2661SO includes the procedures for incorporating the following items on the Maule Models M-7-235 and M-7-235A airplanes:

--An Allison 250-B17C gas turbine engine;

--Edo Model 797-2500 amphibious floats; and

--Hartzell Model HC-B3TF-7A/T10173-11R or HC-B3TF-7A/T10173F-11R propellers.

Note 2: 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 (e) 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 within the next 30 days after the effective date of this AD, unless already accomplished.

To prevent loss of airplane control or engine overspeed with 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) Amend the Limitations Section of the airplane flight manual (AFM) by inserting the following language:

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

(b) This action may be accomplished by incorporating a copy of this AD into the Limitations Section of the AFM.

(c) Amending the AFM, as required by this AD, may be performed by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and must be entered into the aircraft records showing compliance with this AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9).

(d) 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.

(e) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Atlanta Aircraft Certification Office (ACO), Campus Building, 1701 Columbia Avenue, suite 2-160, College Park, Georgia 30337-2748. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO.

Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.

(f) Information related to this AD may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

(g) This amendment (39-10257) becomes effective on January 28, 1998.

Events Leading to the Issuance of This AD

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to all MAULE Models MXT-7-420 and MX-7-420 airplanes and all Models M-7-235 and M-7-235A airplanes that are modified in accordance with STC SA2661SO was published in the Federal Register as a notice of proposed rulemaking (NPRM) on July 24, 1997 (62 FR 39789).

The NPRM proposed to require amending the Limitations Section of the AFM to prohibit the positioning of the power levers below the flight idle stop while the airplane is in flight, including a statement of consequences if the limitation is not followed. This AFM amendment shall consist of the following language:

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

The NPRM was the result of numerous incidents and five documented accidents involving airplanes equipped with turboprop engines where the propeller beta was improperly utilized during flight.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination

After careful review of all available information related to the subject presented above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. The FAA has determined that these minor corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.

Compliance Time of This AD

The FAA has determined that the compliance time of this AD should be specified in calendar time insteadof hours time-in-service. While the condition addressed by this AD is unsafe while the airplane is in flight, the condition is not a result of repetitive airplane operation; the potential of the unsafe condition occurring is the same on the first flight as it is for subsequent flights. The compliance time of "30 days after the effective date of this AD" will not inadvertently ground airplanes and would assure that all owners/operators of the affected airplanes accomplish this AD in a reasonable time period.

Cost Impact

The FAA estimates that 3 airplanes in the U.S. registry will be affected by this AD, that it will take approximately 1 workhour per airplane to incorporate the required AFM amendment, and that the average labor rate is approximately $60 an hour. Since an owner/ operator who holds at least a private pilot's certificate can accomplish this AD, as authorized by sections 43.7 and 43.9 of the Federal Aviation Regulations (14 CFR 43.7 and 43.9), the only cost impact upon the public is the time it will take the affected airplane owner/operators to amend the AFM.

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 copy of thefinal 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.

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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows:

Information related to this AD may be examined at the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 97-CE-40-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Wayne A. Shade, Aerospace Engineer, FAA, Atlanta Certification Office, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone (770) 703-6094; facsimile (770) 703-6097.