[Federal Register Volume 61, Number 167 (Tuesday, August 27, 1996)]
[Proposed Rules]
[Pages 44004-44006]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-21745]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-NM-80-AD]
RIN 2120-AA64


Airworthiness Directives; Fokker Model F27 Mark 100, 200, 300, 
400, 500, 600, and 700 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all Fokker Model F27 Mark 100, 
200, 300, 400, 500, 600, and 700 series airplanes. This proposal would 
require replacement of certain rudder horn assemblies with a new 
assembly. For certain airplanes, the proposed AD also would require 
replacement of certain rudder control rods with a new rod. This 
proposal is prompted by reports of cracked rudder horns and a cracked 
rudder control rod, caused by impact overload. The actions specified by 
the proposed AD are intended to prevent such an overload and consequent 
cracking of the subject parts, which could result in reduced structural 
integrity of the rudder horn assembly or loss of rudder control; this 
condition could lead to reduced controllability of the airplane.


[[Page 44005]]


DATES: Comments must be received by October 7, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-80-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056. Comments may be inspected at this location 
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal 
holidays.
    The service information referenced in the proposed rule may be 
obtained from Fokker Aircraft USA, Inc., 1199 North Fairfax Street, 
Alexandria, Virginia 22314. This information may be examined at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Ruth Harder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-1721; fax (206) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 96-NM-80-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules 
Docket No. 96-NM-80-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Rijksluchtvaartdienst (RLD), which is the airworthiness 
authority for the Netherlands, recently notified the FAA that an unsafe 
condition may exist on all Fokker Model F27 Mark 100, 200, 300, 400, 
500, 600, and 700 series airplanes. The RLD advises it has received 
reports of cracked rudder horns and a cracked rudder control rod found 
on these airplanes. Investigation revealed the cause of such cracking 
has been attributed to an impact overload on the rudder horn assembly. 
The existing design of the rudder horn assembly allows the rudder to 
swing around in heavy gust conditions. The inertia of the rudder 
swinging movement can cause an impact overload when one of the rudder 
limit stops is hit. This condition, if not corrected, could result in 
reduced structural integrity of the rudder horn assembly or loss of 
rudder control, and, consequently, lead to reduced controllability of 
the airplane.

Explanation of Relevant Service Information

    Fokker has issued Service Bulletin F27/27-131, Revision 1, dated 
June 15, 1994, which describes procedures for replacement of the rudder 
horn assembly, having part number (P/N) 3401-042-901 or -401, with a 
new rudder horn assembly, having P/N F3402-070-407. The new rudder horn 
is made of a stronger aluminum alloy material. Additionally, for 
certain airplanes, the service bulletin recommends replacement of the 
rudder control rod, having P/N 5233-018-xxx, with a new rudder control 
rod, having P/N F8507-052-403. The new control rod contains regreasable 
bearings which are less sensitive to seizure. The RLD classified this 
service bulletin as mandatory and issued Dutch airworthiness directive 
BLA 94-105 (A), dated August 5, 1994, in order to assure the continued 
airworthiness of these airplanes in the Netherlands.

FAA's Conclusion

    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 21.29) 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 Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design, the 
proposed AD would require replacement of certain rudder horn assemblies 
with a new rudder horn assembly. For certain airplanes, the proposed AD 
also would require replacement of certain rudder control rods with a 
new rudder control rod. The actions would be required to be 
accomplished in accordance with the service bulletin described 
previously.

Cost Impact

    The FAA estimates that 34 Fokker Model F27 Mark 100, 200, 300, 400, 
500, 600, and 700 series airplanes of U.S. registry would be affected 
by this proposed AD.
    It would take approximately 7 work hours per airplane to accomplish 
the proposed replacement of the rudder horn assembly, at an average 
labor rate of $60 per work hour. Required parts would cost 
approximately $2,565 per airplane. Based on these figures, the cost 
impact of the replacement of the rudder horn assembly proposed by this 
AD on U.S. operators is estimated to be $101,490, or $2,985 per 
airplane.
    There currently are no Fokker Model F27 Mark 100, 200, 300, 400, 
500, 600, or 700 series airplanes on the U.S. Register that would 
require the replacement of the rudder control rod. The only airplanes 
that would require this replacement 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 inclusion 
of that requirement in this proposed rule is necessary to ensure that 
the unsafe condition is addressed in the event that any of these 
airplanes are imported and placed on the U.S. Register in the future.
    Should any of those airplanes (having serial numbers 10102, and 
10105 through 10165, inclusive) be imported and placed on the U.S. 
Register in the future, it would take approximately 5 work hours per 
airplane to accomplish the proposed replacement of the rudder control 
rod, at an average labor rate of $60 per work hour. Required parts 
would cost approximately $635 per

[[Page 44006]]

airplane. Based on these figures, the cost impact of the replacement of 
the rudder control rod proposed by this AD on U.S. operators is 
estimated to be $935 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the proposed 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 proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 draft 
regulatory 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.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:

Fokker: Docket 96-NM-80-AD.
    Applicability: All Model F27 Mark 100, 200, 300, 400, 500, 600, 
and 700 series airplanes, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 an impact overload and consequent cracking of the 
subject parts, which could result in reduced structural integrity of 
the rudder horn assembly or loss of rudder control, and, 
consequently, lead to reduced controllability of the airplane, 
accomplish the following:
    (a) Within 18 months after the effective date of this AD, 
accomplish paragraph (a)(1) and (a)(2) of this AD, as applicable, in 
accordance with Fokker Service Bulletin F27/27-131, Revision 1, 
dated June 15, 1994.
    (1) For all airplanes: Replace the rudder horn assembly, having 
part number (P/N) 3401-042-901 or 3401-042-401, with a new rudder 
horn assembly, having P/N F3402-070-407, in accordance with Part 1 
of the Accomplishment Instructions of the service bulletin.
    (2) For airplanes having serial numbers 10102, and 10105 through 
10165 inclusive: Replace the rudder control rod, having P/N 5233-
018-xxx, with a new rudder control rod, having P/N F8507-052-403, in 
accordance with Part 2 of the Accomplishment Instructions of the 
service bulletin.
    (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, Standardization Branch, ANM-113, 
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, 
Standardization Branch, ANM-113.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.
    (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.

    Issued in Renton, Washington, on August 20, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-21745 Filed 8-26-96; 8:45 am]
BILLING CODE 4910-13-U