[Federal Register Volume 65, Number 24 (Friday, February 4, 2000)]
[Rules and Regulations]
[Pages 5424-5425]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-2393]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-51-AD; Amendment 39-11548; AD 2000-0230]
RIN 2120-AA64


Airworthiness Directives; Twin Commander Aircraft Corporation 600 
Series Airplanes

AGENCY:  Federal Aviation Administration, DOT.

ACTION:  Final rule.

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SUMMARY:  This document adopts a new airworthiness directive (AD) that 
applies to all Twin Commander Aircraft Corporation (Twin Commander) 600 
series airplanes. This AD requires you to revise the Airplane Flight 
Manual (AFM) to include requirements for activating the airframe 
pneumatic deicing boots. This AD is the result of reports of in-flight 
incidents and an accident that occurred in icing conditions where the 
airframe pneumatic deicing boots were not activated. The actions 
specified by this AD are intended to assure that flightcrews have the 
information necessary to activate the pneumatic wing and tail deicing 
boots at the first signs of ice accumulation. Without this information, 
flightcrews could experience reduced controllability of the aircraft 
due to adverse aerodynamic effects of ice adhering to the airplane 
prior to the first deicing cycle.

DATES:  Effective March 24, 2000.

ADDRESSES:  You may examine related information at the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 99-CE-51-AD, 901 Locust, Room 506, Kansas 
City, Missouri 64106.

FOR FURTHER INFORMATION CONTACT:  Mr. John P. Dow, Sr., Aerospace 
Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 506, Kansas 
City, Missouri 64106; telephone: (816) 329-4121; facsimile: (816) 329-
4090.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

What Caused This AD?

    This AD is the result of reports of in-flight incidents and an 
accident that occurred in icing conditions where the airframe pneumatic 
deicing boots were not activated.

What is the Potential Impact if the FAA Took No Action?

    The information necessary to activate the pneumatic wing and tail 
deicing boots at the first signs of ice accumulation is critical for 
flight in icing conditions. If we did not take action to include this 
information, flight crews could experience reduced controllability of 
the aircraft due to adverse aerodynamic effects of ice adhering to the 
airplane prior to the first deicing cycle.

Has the FAA Taken Any Action to This Point?

    Yes. We issued a proposal to amend part 39 of the Federal Aviation 
Regulations (14 CFR part 39) to include an AD that would apply to all 
Twin Commander 600 series airplanes. This proposal was published in the 
Federal Register as a notice of proposed rulemaking (NPRM) on October 
8, 1999 (64 FR 55191). The NPRM proposed to require revising the 
Limitations Section of the AFM to include requirements for activating 
the pneumatic deicing boots at the first indication of ice accumulation 
on the airplane.

Was the Public Invited To Comment?

    Yes. Interested persons were 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.

What Is the FAA's Final Determination on This Issue?

    We carefully reviewed all available information related to the 
subject presented above and determined that air safety and the public 
interest require the adoption of the rule as proposed except for minor 
editorial corrections. We 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.

Cost Impact

How Many Airplanes Does This AD Impact?

    We estimate that 988 airplanes in the U.S. registry will be 
affected.

What Is the Cost Impact of the Affected Airplanes on the U.S. Register?

    There is no dollar cost impact. We estimate that to accomplish the 
AFM revision it will take you less than 1 workhour. You can accomplish 
this action if you hold at least a private pilot certificate as 
authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 
43.7). You must make an entry into the aircraft records that shows 
compliance with this 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 will take you to insert the information into the AFM.

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.
    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

[[Page 5425]]

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. The FAA 
has prepared a final evaluation and placed it in the Rules Docket. You 
can get a copy of this evaluation at the location listed 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:

2000-02-30  Twin Commander Aircraft Corporation: Amendment 39-11548; 
Docket No. 99-CE-51-AD.

    (a) What airplanes are affected by this AD? The following Model 
600 series airplanes, all serial numbers, that are:
    (1) Equipped with pneumatic deicing boots; and
    (2) Certificated in any category.

Models

680, 680E, 680F, 680FL, 680FL(P), 680T, 680V, 680W, 681, 690, 685, 
690A, 690B, 690C, 690D, 695, 695A, and 695B

    (b) Who must comply with this AD? Anyone who wishes to operate 
any of the above airplanes on the U.S. Register. The AD does not 
apply to your airplane if it is not equipped with pneumatic deicing 
boots.
    (c) What problem does this AD address? The information necessary 
to activate the pneumatic wing and tail deicing boots at the first 
signs of ice accumulation is critical for flight in icing 
conditions. If we did not take action to include this information, 
flight crews could experience reduced controllability of the 
aircraft due to adverse aerodynamic effects of ice adhering to the 
airplane prior to the first deicing cycle.
    (d) What must I do to address this problem? To address this 
problem, you must revise the Limitations Section of the FAA-approved 
Airplane Flight Manual (AFM) to include the following requirements 
for activation of the ice protection systems. You must accomplish 
this action within the next 10 calendar days after the effective 
date of this AD, unless already accomplished. You may insert a copy 
of this AD in the AFM to accomplish this action:
    '' Except for certain phases of flight where the AFM 
specifies that deicing boots should not be used (e.g., take-off, 
final approach, and landing), compliance with the following is 
required.
     Wing and Tail Leading Edge Pneumatic Deicing Boot 
System, if installed, must be activated:

--At the first sign of ice formation anywhere on the aircraft, or 
upon annunciation from an ice detector system, whichever occurs 
first; and
--The system must either be continued to be operated in the 
automatic cycling mode, if available; or the system must be manually 
cycled as needed to minimize the ice accretions on the airframe.

     The wing and tail leading edge pneumatic deicing boot 
system may be deactivated only after leaving icing conditions and 
after the airplane is determined to be clear of ice.''
    (e) Can the pilot accomplish the action? Yes. Anyone who holds 
at least a private pilot certificate, as authorized by section 43.7 
of the Federal Aviation Regulations (14 CFR 43.7), may incorporate 
the AFM revisions required by this AD. You must make an entry into 
the aircraft records that shows compliance with this AD, in 
accordance with section 43.9 of the Federal Aviation Regulations (14 
CFR 43.9).
    (f) Can I comply with this AD in any other way? Yes.
    (1) You may use an alternative method of compliance or adjust 
the compliance time if:
    (i) Your alternative method of compliance provides an equivalent 
level of safety; and
    (ii) The Manager, Small Airplane Directorate, approves your 
alternative. Submit your request through an FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager.
    (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 (f)(1) 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 you have not eliminated the unsafe 
condition, specific actions you propose to address it.
    (g) Where can I get information about any already approved 
alternative methods of compliance? Contact the Small Airplane 
Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; 
telephone: (816) 329-4121; facsimile: (816) 329-4091.
    (h) What if I need to fly the airplane to another location to 
comply with this AD? The FAA can issue a special flight permit under 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate your airplane to a location where 
you can accomplish the requirements of this AD.
    (i) When does this amendment become effective? This amendment 
becomes effective on March 24, 2000.

    Issued in Kansas City, Missouri, on January 25, 2000.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 00-2393 Filed 2-3-00; 8:45 am]
BILLING CODE 4910-13-P