[Federal Register Volume 59, Number 205 (Tuesday, October 25, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-26371]
[[Page Unknown]]
[Federal Register: October 25, 1994]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-CE-10-AD]
Airworthiness Directives; Pilatus Britten-Norman BN2A, BN2B, and
BN2T Islander Series and BN2A Mk III Trislander Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes to adopt a new airworthiness directive
(AD) that would apply to Pilatus Britten-Norman BN2A, BN2B, and BN2T
Islander and BN2A Mk III Trislander series airplanes that are equipped
with a nose wheel steering disconnect system with either a Modification
NB/M/503 or Modification NB/M/733 nose undercarriage unit. The proposed
action would require repetitively inspecting the nose wheel steering
drive ring for cracks, and replacing any cracked drive ring. A report
of the rudder pedals jamming in the central position during a takeoff
on one of the affected airplanes prompted the proposed action. The
actions specified by the proposed AD are intended to prevent failure of
the nose wheel steering system because of a cracked drive ring, which
could result in the inability to move the rudder pedals.
DATES: Comments must be received on or before December 30, 1994.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Central Region, Office of the Assistant Chief
Counsel, Attention: Rules Docket No. 94-CE-10-AD, Room 1558, 601 E.
12th Street, Kansas City, Missouri 64106. Comments may be inspected at
this location between 8 a.m. and 4 p.m., Monday through Friday,
holidays excepted.
Service information that applies to the proposed AD may be obtained
from Pilatus Britten-Norman Ltd, Bembridge, Isle of Wight, United
Kingdom, PO35 5PR. This information also may be examined at the Rules
Docket at the address above.
FOR FURTHER INFORMATION CONTACT:
Mr. Delano D. Castle, Program Manager, Brussels Aircraft Certification
Office, FAA, Europe, Africa, and Middle East Office, c/o American
Embassy, B-1000 Brussels, Belgium; telephone (322) 513.3830, extension
2716; facsimile (322) 230.6899; or Mr. John P. Dow, Sr., Project
Officer, Small Airplane Directorate, Airplane Certification Service,
FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106; telephone
(816) 426-6932; facsimile (816) 426-2169.
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 should 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 that summarizes 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 No. 94-CE-10-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, Central Region, Office of the Assistant Chief Counsel,
Attention: Rules Docket No. 94-CE-10-AD, Room 1558, 601 E. 12th Street,
Kansas City, Missouri 64106.
Discussion
The Civil Aviation Authority (CAA), which is the airworthiness
authority for the United Kingdom, recently notified the FAA that an
unsafe condition may exist on Pilatus Britten-Norman BN2A, BN2B, and
BN2T Islander and BN2A Mk III Trislander series airplanes that are
equipped with a nose wheel steering disconnect system with either a
Modification NB/M/503 or Modification NB/M/733 nose undercarriage unit.
The CAA advises that the rudder pedals jammed in the central position
during a takeoff run on a BN2B Islander series airplane. Initial
investigation revealed that the nose wheel steering drive ring had
fractured and the broken portion of the ring became snagged in the cut-
away section of frame 19 where the steering cables pass through. This
caused the inability to move the rudder pedals. Further investigation
showed that the drive ring had cracked from the small radius of the
left front lug across the ring and also through the grease nipple hole
at the rear left side of the ring.
Pilatus Britten-Norman has issued Service Bulletin No. BN-2/SB.214,
Issue 1, dated September 23, 1993, which specifies procedures for
inspecting the nose wheel steering drive ring. In order to assure the
continued airworthiness of these airplanes in the United Kingdom, the
CAA listed the actions specified in this service bulletin in the
Mandatory Aircraft Modifications and Inspections Summary, Issue 8,
dated March 1994, as UK CAA AD 005-09-93.
This airplane model is manufactured in the United Kingdom and is
type certificated for operation in the United States under the
provisions of Sec. 21.29 of the Federal Aviation Regulations (14 CFR
21.29) and the applicable bilateral airworthiness agreement. Pursuant
to this bilateral airworthiness agreement, the CAA has kept the FAA
informed of the situation described above.
The FAA has examined the findings of the CAA, 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.
Since an unsafe condition has been identified that is likely to
exist or develop in other Pilatus Britten- Norman BN2A, BN2B, and BN2T
Islander and BN2A Mk III Trislander series airplanes of the same type
design that are equipped with a nose wheel steering disconnect system
with either a Modification NB/M/503 or Modification NB/M/733 nose
undercarriage unit, the proposed AD would require repetitively
inspecting the nose wheel steering drive ring for cracks, and replacing
any cracked drive ring. The proposed inspection would be accomplished
in accordance with Pilatus Britten-Norman Service Bulletin No. BN-2/
SB.214, Issue 1, dated September 23, 1993. The drive ring replacement,
if necessary, would be accomplished in accordance with the applicable
maintenance manual.
The FAA estimates that 15 airplanes in the U.S. registry would be
affected by the proposed AD, that it would take approximately 1
workhour per airplane to accomplish the proposed action, and that the
average labor rate is approximately $55 an hour. Based on these
figures, the total cost impact of the proposed AD on U.S. operators is
estimated to be $825. This figure does not take into account the cost
of repetitive inspections nor the cost of replacing any cracked drive
ring. The FAA has no way of determining how many repetitive inspections
each operator would incur over the lifetime of the airplane or how many
drive rings may be cracked.
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 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) 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 has been placed 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. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding a new AD to read as follows:
Pilatus Britten-Norman: Docket No. 94-CE-10-AD.
Applicability: BN2A, BN2B, and BN2T Islander and BN2A Mk III
Trislander series airplanes, certificated in any category, that are
equipped with a nose wheel steering disconnect system with either a
Modification NB/M/503 or Modification NB/M/733 nose undercarriage
unit.
Compliance: Required within the next 100 hours time-in-service
(TIS), unless already accomplished, and thereafter at intervals not
to exceed 100 hours TIS.
To prevent failure of the nose wheel steering system because of
a cracked drive ring, which could result in the inability to move
the rudder pedals, accomplish the following:
(a) Visually inspect the nose wheel steering drive ring for
cracks in accordance with the ACTION section of Pilatus Britten-
Norman Service Bulletin No. BN-2/SB.214, Issue 1, dated September
23, 1993. Prior to further flight, replace any cracked nose wheel
steering drive ring in accordance with the applicable maintenance
manual.
(b) Special flight permits may be issued in accordance with
Secs. 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.
(c) An alternative method of compliance or adjustment of the
initial or repetitive compliance time that provides an equivalent
level of safety may be approved by the Manager, Brussels Aircraft
Certification Office, FAA, Europe, Africa, and Middle East Office,
c/o American Embassy, B-1000 Brussels, Belgium. The request should
be forwarded through an appropriate FAA Maintenance Inspector, who
may add comments and then send it to the Manager, Brussels Aircraft
Certification Office.
Note: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Brussels Aircraft Certification Office.
(d) All persons affected by this directive may obtain copies of
the document referred to herein upon request to Pilatus Britten-
Norman Ltd, Bembridge, Isle of Wight, United Kingdom, PO35 5PR; or
may examine this document at the FAA, Central Region, Office of the
Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City,
Missouri 64106. Issued in Kansas City, Missouri, on October 19,
1994.
John R. Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-26371 Filed 10-24-94; 8:45 am]
BILLING CODE 4910-13-U
