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Airworthiness Directive packet

AD 97-26-14

Airworthiness Directives; MAULE Models MX-7-420 and MXT-7-420 Airplanes and Models M-7-235 and M-7-235A Airplanes Modified in Accordance With Maule Supplemental Type Certificate (STC) SA2661SO

1 · Quick read — prepared by AircraftDirectives

Our plain-language summary — not the regulation

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.

AD number
97-26-14
Federal Register document
97-32990
Citation
62 FR 66269
Amendment
39-10257
Docket
Docket No. 97-CE-40-AD
Action
Final rule.
Published
1997-12-18
Effective (as stated in the rule)
January 28, 1998.
Issued by
Transportation Department, Federal Aviation Administration
Regulation
14 CFR 39
Applies to (in our index)
Maule M-Series

2 · Official Federal Register document — government source, verbatim

Reproduced unedited from the Federal Register
[Federal Register Volume 62, Number 243 (Thursday, December 18, 1997)]
[Rules and Regulations]
[Pages 66269-66271]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-32990]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-40-AD; Amendment 39-10257; AD 97-26-14]
RIN 2120-AA64


Airworthiness Directives; MAULE Models MX-7-420 and MXT-7-420 
Airplanes and Models M-7-235 and M-7-235A Airplanes Modified in 
Accordance With Maule Supplemental Type Certificate (STC) SA2661SO

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that

[[Page 66270]]

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 below the flight idle stop while the airplane 
is in flight.

EFFECTIVE DATE: January 28, 1998.

ADDRESSES: 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.

FOR FURTHER INFORMATION CONTACT: 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.

SUPPLEMENTARY INFORMATION:

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 instead of 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 the final 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:

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

[[Page 66271]]

--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.

    Issued in Kansas City, Missouri, on December 10, 1997.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 97-32990 Filed 12-17-97; 8:45 am]
BILLING CODE 4910-13-U

Sources. Section 1 is written by AircraftDirectives from the record below and is a reading aid only. Section 2 is the United States Government's own text, reproduced without edit.

Federal Register: https://www.federalregister.gov/documents/1997/12/18/97-32990/airworthiness-directives-maule-models-mx-7-420-and-mxt-7-420-airplanes-and-models-m-7-235-and

Official PDF: https://www.govinfo.gov/content/pkg/FR-1997-12-18/pdf/97-32990.pdf

Packet generated 2026-08-18 08:18 UTC.

This packet is not an airworthiness determination and not legal or maintenance advice. AircraftDirectives reproduces official records and condenses their wording for easier reading. It does not decide, certify or imply whether any aircraft, engine, appliance or part is airworthy, compliant, affected by this directive, or eligible for return to service. No inspection, approval, or determination of any kind is performed or implied by this document.

Section 1 is a reading aid, not the rule. It is our own plain-language condensation, written to help a reader find the relevant directive quickly. It is NOT a substitute for the regulation, it may omit conditions, exceptions, compliance times, alternative methods of compliance (AMOCs) and applicability limits, and it has no legal force whatsoever. Only the official text governs. Where Section 1 and Section 2 differ in any respect, Section 2 - and the official source it was retrieved from - controls absolutely.

Responsibility remains with the owner/operator. Under 14 CFR §91.403 and §91.417 the owner or operator is responsible for maintaining airworthiness and for required records; under §39.7 no person may operate a product to which an airworthiness directive applies except in accordance with that directive. Determining applicability to a specific serial number and configuration, and performing or supervising any required action, is the responsibility of the owner/operator and appropriately certificated personnel.

Accuracy and currency. Section 2 was retrieved at the time stamped above and is reproduced without edit; Federal Register material is a work of the United States Government. Directives are amended, corrected and superseded over time, and this sheet is a snapshot, not a live record - it does not update after printing. Re-check the official sources before acting on it. This packet is provided without warranty of any kind, express or implied, including fitness for a particular purpose. We do not sell parts and have no commercial interest in any action a directive may require.

AircraftDirectives · AD 97-26-14 · Section 1 is our plain-language reading aid; Section 2 is the official Federal Register text and controls where the two differ. Not an airworthiness determination — 14 CFR §91.403 / §91.417 responsibility remains with the owner/operator. Retrieved 2026-08-18 08:18 UTC.