[Federal Register Volume 65, Number 35 (Tuesday, February 22, 2000)]
[Rules and Regulations]
[Pages 8651-8653]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-3885]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-139-AD; Amendment 39-11585; AD 2000-04-03]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Models DC-3 and DC-4 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain McDonnell Douglas Models DC-3 and DC-4 series 
airplanes that requires an inspection to determine the type of airframe 
pneumatic deicing boots installed. This amendment also requires 
revising the Airplane Flight Manual (AFM) to include requirements for 
activation of the pneumatic deicing boots for those airplanes equipped 
with ``modern'' boots. This amendment is prompted by reports of 
inflight 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 ensure that flightcrews 
activate the pneumatic wing and tail deicing boots at the first signs 
of ice accumulation. This action will prevent reduced controllability 
of the aircraft due to adverse aerodynamic effects of ice adhering to 
the airplane prior to the first deicing cycle.

EFFECTIVE DATE: Effective March 28, 2000.

ADDRESSES: Information pertaining to this amendment may be examined at 
the Federal Aviation Administration (FAA), Transport Airplane 
Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; 
or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT: Albert Lam, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Transport Airplane 
Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount 
Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5346; 
fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain McDonnell Douglas Models 
DC-3 and DC-4 series airplanes was published as a supplemental notice 
of proposed rulemaking (NPRM) in the Federal Register on November 18, 
1999 (64 FR 62993). That action proposed to require

[[Page 8652]]

an inspection to determine the type of airframe pneumatic deicing boots 
installed. That action also proposed to require revising the Airplane 
Flight Manual (AFM) to include requirements for activation of the 
pneumatic deicing boots for those airplanes equipped with ``modern'' 
boots.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were submitted in response 
to the proposal or the FAA's determination of the cost to the public.

Addition of Note 2

    The FAA has added a new Note 2 that provides an explanation of the 
term ``visual inspection'' as specified in paragraph (a) of the final 
rule.

Conclusion

    After careful review of the available data, the FAA has determined 
that air safety and the public interest require the adoption of the 
rule with the changes previously described. The FAA has determined that 
these changes will neither increase the economic burden on any operator 
nor increase the scope of the AD.

Cost Impact

    The FAA estimates that 166 airplanes of U.S. registry will be 
affected by this AD.
    The FAA estimates that it will take approximately 2 work hours per 
airplane to accomplish the required actions, at the average labor rate 
of $60 per work hour. Based on these figures, the cost impact of this 
AD on U.S. operators is estimated to be $19,920, or $120 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the requirements of this AD 
action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.

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 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.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

2000-04-03  McDonnell Douglas: Amendment 39-11585. Docket 99-NM-139-
AD.

    Applicability: Models DC-3 and DC-4 series airplanes equipped 
with pneumatic deicing boots, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure that flightcrews activate the wing and tail pneumatic 
deicing boots at the first signs of ice accumulation on the 
airplane, accomplish the following:

    Note 1: For the purposes of this AD, the following definitions 
of ``older'' and ``modern'' apply:

    ``Modern'' pneumatic boot systems may be characterized by short 
segmented, small diameter tubes, which are operated at relatively 
high pressures [18-23 pounds per square inch (psi)] by excess bleed 
air that is provided by turbine engines. ``Older'' pneumatic boot 
systems may be characterized by long, uninterrupted, large diameter 
tubes, which were operated at low pressures by engine driven 
pneumatic pumps whose pressure varied with engine revolutions per 
minute (rpm). This low pressure coupled with long and large diameter 
tubes caused early de-ice systems to have very lengthy inflation and 
deflation cycles and dwell times. (Dwell time is the period of time 
that the boot remains fully expanded following the completion of the 
inflation cycle until the beginning of the deflation cycle.)
    (a) Within 10 days after the effective date of this AD: Perform 
a visual inspection to determine if the type of pneumatic deicing 
boots installed is either ``older'' or ``modern'' boots.

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''

    (1) For those airplanes equipped with ``older'' pneumatic 
deicing boots, no further action is required by this AD.
    (2) For those airplanes equipped with ``modern'' pneumatic 
deicing boots, within 10 days after the inspection required by 
paragraph (a) of this AD: Revise the Limitations Section of the FAA-
approved Airplane Flight Manual (AFM) to include the following 
requirements for activation of the ice protection systems. This may 
be accomplished by inserting a copy of this AD in the AFM.
    `` 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.''

Alternative Methods of Compliance

    (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, Los Angeles Aircraft Certification 
Office, Transport Airplane Directorate. The request shall be 
forwarded through an appropriate FAA Operations Inspector, who may 
add comments and then send it to the Manager, Los Angeles ACO.

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

Special Flight Permits

    (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.

[[Page 8653]]

    (d) This amendment becomes effective on March 28, 2000.

    Issued in Renton, Washington, on February 14, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-3885 Filed 2-18-00; 8:45 am]
BILLING CODE 4910-13-U