Airworthiness Directives; de Havilland Inc. Models DHC-6-1, DHC- 6-100, DHC-6-200, and DHC-6-300 Airplanes

[Federal Register Volume 64, Number 168 (Tuesday, August 31, 1999)]
[Rules and Regulations]
[Pages 47374-47376]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-22535]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-10-AD; Amendment 39-11279; AD 99-18-13]
RIN 2120-AA64


Airworthiness Directives; de Havilland Inc. Models DHC-6-1, DHC-
6-100, DHC-6-200, and DHC-6-300 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to all de Havilland Inc.
    Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 airplanes. This 
AD requires amending the Limitations Section of the airplane flight 
manual (AFM) to prohibit the positioning of the power levers aft of the 
flight idle stop while the airplane is in flight. The AFM amendment 
includes a statement of consequences if the limitation is not followed. 
This AD is a result of numerous incidents and five documented accidents 
involving airplanes equipped with turboprop engines where the propeller 
beta was improperly utilized during flight. None of the incidents or 
accidents involved de Havilland Inc. Models DHC-6-1, DHC-6-100, DHC-6-
200, and DHC-6-300 airplanes. 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 aft of the flight idle stop while the airplane is in flight.

EFFECTIVE DATE: October 8, 1999.

ADDRESSES: This information may be examined at the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 97-CE-10-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

FOR FURTHER INFORMATION CONTACT: Peter LeVoci, Flight Test Pilot, FAA, 
New York Aircraft Certification Office, 10 Fifth Street, Third Floor, 
Valley Stream, New York 11581; telephone: (516) 256-7514; facsimile: 
(516) 568-2716.

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 de Havilland 
Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 airplanes was 
published in the Federal Register as a notice of proposed rulemaking 
(NPRM) on October 22, 1998 (63 FR 56582). The NPRM proposed to require 
amending the Limitations Section of the AFM to prohibit the positioning 
of the power levers aft of 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 aft of 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.

    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. None of the 
incidents or accidents involved de Havilland Inc. Models DHC-6-1, DHC-
6-100, DHC-6-200, and DHC-6-300 airplanes.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the one comment received.

Comment Disposition

    The commenter supports the AD as written and believes that the FAA

[[Page 47375]]

should issue additional AD action that mandates a modification that 
would prevent the flight crews from intentionally or inadvertently 
selecting the power levers below the flight idle stop while in flight. 
The commenter suggests this modification be in the form of a mechanical 
lockout device to preclude such power lever selection.
    The FAA is currently evaluating each of the aircraft where AD's 
were issued to address this issue with a flight manual revision. The 
purpose of this evaluation is to determine whether a mechanical lockout 
device is necessary. Among those aircraft the FAA is evaluating are the 
de Havilland DHC-6 series airplanes. If the FAA determines that such a 
device is necessary, additional rulemaking may be initiated. No changes 
have been made to the final rule as a result of this comment.

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 will 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 will assure that all owners/operators of the 
affected airplanes accomplish this action in a reasonable time period.

Cost Impact

    The FAA estimates that 114 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 1 workhour per 
airplane to incorporate the AFM amendment, and that the average labor 
rate is approximately $60 an hour. Accomplishing the AFM revision 
requirements of 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 the AD in accordance 
with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9). 
The only cost impact of this AD is the time it would take each owner/
operator of the affected airplanes to insert the information into 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:
99-18-13  De Havilland Inc: Amendment 39-11279; Docket No. 97-CE-10-
AD.

    Applicability: Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-
300 airplanes, all serial numbers, 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 (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 aft of 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 aft of 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) 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, FAA, New York Aircraft Certification Office 
(ACO), 10 Fifth Street, Third Floor, Valley Stream, New York 11581. 
The request shall be forwarded through an appropriate FAA 
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.

    (f) This amendment becomes effective on October 8, 1999.


[[Page 47376]]


    Issued in Kansas City, Missouri, on August 23, 1999.
Terry L. Chasteen,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-22535 Filed 8-30-99; 8:45 am]
BILLING CODE 4910-13-U

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