[Federal Register Volume 62, Number 250 (Wednesday, December 31, 1997)]
[Rules and Regulations]
[Pages 68159-68161]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-34040]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-255-AD; Amendment 39-10267; AD 98-01-03]
RIN 2120-AA64


Airworthiness Directives; Fokker Model F27 Mark 050 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Fokker Model F27 Mark 050 series airplanes. This 
action requires modification of the air outlet opening of the engine 
air bypass duct. This amendment is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified in this AD are intended to prevent 
accumulation of ice in the engine air intake duct and subsequent 
ingestion of ice into the engine, which could result in engine power 
fluctuations and reduced controllability of the airplane.

DATES: Effective January 15, 1998.

[[Page 68160]]

    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 15, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before January 30, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 97-NM-255-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
Fokker Services B.V., Technical Support Department, P. O. Box 75047, 
1117 ZN Schiphol Airport, the Netherlands. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at the Office of the Federal Register, 800 
North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: International Branch, ANM-116, FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: The Rijksluchtvaartdienst (RLD), which is 
the airworthiness authority for the Netherlands, notified the FAA that 
an unsafe condition may exist on certain Fokker Model F27 Mark 050 
series airplanes. The RLD advises that it has received a report 
indicating that, during icing conditions, power fluctuations occurred 
on both engines of an airplane. The airplane had been modified 
previously in accordance with four service bulletins to improve heating 
of the engine air intake duct and to counteract the effects of 
electromagnetic interference on the engine anti-icing systems; these 
modifications also were introduced in order to prevent power 
fluctuations caused by ingestion of ice into the engines. However, 
service experience has shown that, in certain weather conditions, 
accumulation of ice in the engine air intake duct can still occur, 
allowing ingestion of ice into the engine. This condition, if not 
corrected, could result in engine power fluctuations and reduced 
controllability of the airplane.

Explanation of Relevant Service Information

    Fokker has issued Service Bulletin SBF50-71-041, dated November 10, 
1993, which describes procedures for modification of the air outlet 
opening of the engine air bypass duct. The modification entails 
installing new parts in the engine bottom cowling to enlarge the outlet 
opening. Accomplishment of the actions specified in the service 
bulletin is intended to adequately address the unsafe condition. The 
RLD classified this service bulletin as mandatory and issued Dutch 
airworthiness directive BLA 1995-065 (A), dated June 30, 1995, in order 
to assure the continued airworthiness of these airplanes in the 
Netherlands.

FAA's Conclusions

    This airplane model is manufactured in the Netherlands and is type 
certificated for operation in the United States under the provisions of 
section 21.29 of the Federal Aviation Regulations (14 CFR 21.19) and 
the applicable bilateral airworthiness agreement. Pursuant to this 
bilateral airworthiness agreement, the RLD has kept the FAA informed of 
the situation described above. The FAA has examined the findings of the 
RLD, reviewed all available information, and determined that AD action 
is necessary for products of this type design that are certificated for 
operation in the United States.

Explanation of Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the service bulletin described previously.

Cost Impact

    None of the Model F27 Mark 050 series airplanes affected by this 
action are on the U.S. Register. All airplanes included in the 
applicability of this rule currently are operated by non-U.S. operators 
under foreign registry; therefore, they are not directly affected by 
this AD action. However, the FAA considers that this rule is necessary 
to ensure that the unsafe condition is addressed in the event that any 
of these subject airplanes are imported and placed on the U.S. Register 
in the future.
    Should an affected airplane be imported and placed on the U.S. 
Register in the future, it would require approximately 7 work hours to 
accomplish the required actions, at an average labor rate of $60 per 
work hour. Required parts would cost approximately $2,200. Based on 
these figures, the cost impact of this AD would be $2,620 per airplane.

Determination of Rule's Effective Date

    Since this AD action does not affect any airplane that is currently 
on the U.S. register, it has no adverse economic impact and imposes no 
additional burden on any person. Therefore, prior notice and public 
procedures hereon are unnecessary and the amendment may be made 
effective in less than 30 days after publication in the Federal 
Register. 

Comments Invited

    Although this action is in the form of a final rule and was not 
preceded by notice and opportunity for public comment, comments are 
invited on this rule. Interested persons are invited to comment on this 
rule by submitting such written data, views, or arguments as they may 
desire. Communications shall identify the Rules Docket number and be 
submitted in triplicate to the address specified under the caption 
ADDRESSES. All communications received on or before the closing date 
for comments will be considered, and this rule may be amended in light 
of the comments received. Factual information that supports the 
commenter's ideas and suggestions is extremely helpful in evaluating 
the effectiveness of the AD action and determining whether additional 
rulemaking action would be needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-NM-255-AD.'' The postcard will be date stamped and 
returned to the commenter.

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.

[[Page 68161]]

    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, Incorporation by 
reference, 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:
98-01-03 Fokker: Amendment 39-10267. Docket 97-NM-255-AD.

    Applicability: Model F27 Mark 050 series airplanes, serial 
numbers 20103 through 20296 inclusive, 20304, 20305, 20308, and 
20311; 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 (b) 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 as indicated, unless accomplished 
previously.
    To prevent accumulation of ice in the engine air intake duct and 
subsequent ingestion of ice into the engine, which could result in 
engine power fluctuations and reduced controllability of the 
airplane, accomplish the following:
    (a) Within 3 months after the effective date of this AD, modify 
the air outlet opening of the engine air bypass duct in the left and 
right bottom engine cowling in accordance with Fokker Service 
Bulletin SBF50-71-041, dated November 10, 1993.
    (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, International Branch, ANM-116, FAA, 
Transport Airplane Directorate. Operators shall submit their 
requests through an appropriate FAA Principal Maintenance Inspector, 
who may add comments and then send it to the Manager, International 
Branch, ANM-116.
    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.
    (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.
    (d) The modification shall be done in accordance with Fokker 
Service Bulletin SBF50-71-041, dated November 10, 1993. This 
incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Fokker Services B.V., Technical 
Support Department, P. O. Box 75047, 1117 ZN Schiphol Airport, the 
Netherlands. Copies may be inspected at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.
    Note 3: The subject of this AD is addressed in Dutch 
airworthiness directive BLA 1995-065 (A), dated June 30, 1995.
    (e) This amendment becomes effective on January 15, 1998.

    Issued in Renton, Washington, on December 23, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-34040 Filed 12-30-97; 8:45 am]
BILLING CODE 4910-13-U