[Federal Register Volume 63, Number 166 (Thursday, August 27, 1998)]
[Rules and Regulations]
[Pages 45685-45687]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-22822]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-111-AD; Amendment 39-10723; AD 98-18-07]
RIN 2120-AA64


Airworthiness Directives; Pilatus Britten-Norman Ltd. BN-2, BN-
2A, BN-2B, and BN-2A MK. 111 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to certain Pilatus Britten-Norman Ltd. (PBN) BN-2, BN-2A, BN-
2B, and BN-2A MK. 111 series airplanes that are equipped with a PBN 
Modification NB/M/256, 50A generator system. This AD requires 
inspecting the airplanes that are equipped with a 50A

[[Page 45686]]

generator system for a 70A generator. If a 70A generator is installed, 
this AD requires replacing the 70A generator with a 50A generator, or 
(for the BN-2, BN-2A, and BN-2B series only) upgrading the airplane 
generator system to a 70A system to match the 70A generator. This AD is 
the result of mandatory continuing airworthiness information (MCAI) 
issued by the airworthiness authority for the United Kingdom. The 
actions specified by this AD are intended to detect and correct damage 
to the components of the electrical system, which could result in 
electrical system failure during critical phases of flight.

DATES: Effective October 12, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 12, 1998.

ADDRESSES: Service information that applies to this AD may be obtained 
from Pilatus Britten-Norman, Ltd., Bembridge, Isle of Wight, United 
Kingdom, PO35 5PR. This information may also be examined at the Federal 
Aviation Administration (FAA), Central Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 97-CE-111-AD, Room 1558, 601 E. 
12th Street, Kansas City, Missouri 64106; or at the Office of the 
Federal Register, 800 North Capitol Street, NW, suite 700, Washington, 
DC.

FOR FURTHER INFORMATION CONTACT: Mr. Roger Chudy, Project Officer, FAA, 
Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, 
Missouri, 64106; telephone (816) 426-6932, facsimile (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to certain PBN BN-2, BN-
2A, BN-2B, and BN-2A MK. 111 series airplanes that are equipped with a 
PBN Modification NB/M/256, 50A generator system, was published in the 
Federal Register as a notice of proposed rulemaking (NPRM) on June 9, 
1998 (63 FR 31370). The NPRM proposed to require:
     inspecting the airplane for a 70A generator installed on a 
50A generator system;
     for PBN BN-2A MK. 111 series airplanes, if a 70A generator 
is installed on a 50A generator system, the NPRM proposed to require 
replacing the 70A generator with a 50A generator;
     for the BN-2, BN-2A, and BN-2B series airplanes, the NPRM 
proposed to require either replacing the 70A generator with a 50A 
generator; or upgrading the 50A generator system to a 70A generator 
system by incorporating PBN Modification NB/M/1148; and,
     if PBN Modification NB/M/1148 is incorporated, the NPRM 
proposed to require the incorporation of PBN Modification NB/M/1571 
(which improves the diodes on the 70A generator system).
    Accomplishment of the proposed actions as specified in the NPRM 
would be in accordance with PBN Service Bulletin No. BN-2/SB.229, dated 
October 17, 1996, and PBN Service Bulletin No. BN-2/SB.228, Issue 2, 
dated January 17, 1996.
    The NPRM was the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for the United 
Kingdom.
    Interested persons have been 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.

The FAA's Determination

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of the rule as proposed except for 
minor editorial corrections. The FAA has 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.

This Action as it Relates to Current AD's

    The FAA recently issued AD 98-04-17, Amendment 39-10329 (63 FR 
7696, February 17, 1998), which requires that any PBN BN-2, BN-2A, and 
BN-2B series airplanes that are not equipped with Modification NB/M/
1571, but are equipped with PBN Modification NB/M/1148 (which 
incorporates the 70A generator system) should also be equipped with PBN 
Modification NB/M/1571. AD 98-04-17 does not affect any airplane that 
is equipped with a 50A generator system.
    Since this AD provides an option that requires accomplishment of AD 
98-04-17, the FAA is including reference of other similar AD 
requirements. Operators of BN-2, BN-2A, and BN-2B series airplanes that 
have 70A generators installed on 50A generator systems, and choose the 
option of upgrading their 50A generator system to a 70A generator 
system, will be subject to the requirements in AD 98-04-17. This AD 
concurrently requires installing higher amperage diodes in the 70A 
generator.
    Pilatus Britten-Norman informed the FAA that Modification NB/M/1148 
or Modification NB/M/1571 is not approved for incorporation on the BN-
2A MK. 111 series airplanes.

Cost Impact

    The FAA estimates that 80 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 7 workhours per 
airplane to accomplish this action, and that the average labor rate is 
approximately $60 an hour. Parts cost approximately $500 per airplane. 
Based on these figures, the total cost impact of this AD on U.S. 
operators is estimated to be $73,600, or $920 per airplane.

Compliance Time of This AD

    The condition addressed by this AD is not caused by operation of 
the aircraft where the affected generators are installed. The need for 
the generator system modification or replacement has no correlation to 
the number of times the equipment is utilized or the age of the 
equipment. For this reason, the compliance time of this AD is presented 
in calendar time instead of hours time-in-service (TIS).

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.
    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 copy of the final 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.

[[Page 45687]]

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 a new airworthiness directive 
(AD) to read as follows:

    98-18-07 Pilatus Britten-Norman Ltd.: Amendment 39-10723; Docket 
No. 97-CE-111-AD.

    Applicability: Models BN-2, BN-2A, BN-2A-2, BN-2A-3, BN-2A-6, 
BN-2A-8, BN-2A-9, BN-2A-20, BN-2A-21, BN-2A-26, BN-2A-27, BN-2B-20, 
BN-2B-21, BN-2B-26, BN-2B-27, BN-2A MK. 111, BN-2A MK. 111-2, and 
BN-2A MK. 111-3 airplanes, all serial numbers, certificated in any 
category, that are equipped with PBN Modification NB/M/256, a 50A 
Generator System.

    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 (d) 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 within the next 3 calendar months after the 
effective date of this AD, unless already accomplished.
    To detect and correct damage to the components of the generator 
system, which could result in generator system failure during 
critical phases of flight, accomplish the following:
    (a) Inspect the generator system for the installation of a 70A 
generator in accordance with the Inspection section of Pilatus 
Britten-Norman (PBN) Service Bulletin (SB) No. BN-2/SB.229, dated 
October 17, 1996.
    (b) If a 70A generator is installed, accomplish the following, 
as applicable:
    (1) For Models BN-2, BN-2A, BN-2A-2, BN-2A-3, BN-2A-6, BN-2A-8, 
BN-2A-9, BN-2A-20, BN-2A-21, BN-2A-26, BN-2A-27, BN-2B-20, BN-2B-21, 
BN-2B-26, and BN-2B-27 airplanes, prior to further flight, either:
    (i) Replace the 70A generator with a 50A generator in accordance 
with the Replacement section of PBN SB No. BN-2/SB.229, dated 
October 17, 1996; or
    (ii) Incorporate PBN Modification NB/M/1148 (a 70A generator 
system) in accordance with the appropriate Pilatus Britten-Norman 
maintenance manual; and, incorporate PBN Modification NB/M/1571 
(installation of improved generator diodes) in accordance with PBN 
SB No. BN-2/228, Issue 2, dated January 17, 1996.

    Note 2: Incorporating PBN Modification NB/M/1571 is the same 
action required by AD 98-04-17, Amendment 39-10329.

    (2) For Models BN-2A MK. 111, BN-2A MK. 111-2, and BN-2A MK. 
111-3 airplanes, prior to further flight, replace the 70A generator 
with a 50A generator in accordance with the Replacement section of 
PBN SB No. BN-2/SB.229, dated October 17, 1996.
    (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) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Small Airplane Directorate, 1201 Walnut, 
suite 900, Kansas City, Missouri, 64106. The request shall be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Small Airplane 
Directorate.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.

    (e) Questions or technical information related to PBN Service 
Bulletin No. BN-2/SB.229, dated October 17, 1996, or PBM Service 
Bulletin No. BN-2/SB.228, Issue 2, dated January 17, 1996, should be 
directed to Pilatus Britten-Norman, Ltd., Bembridge, Isle of Wight, 
United Kingdom, PO35 5PR. This service information may be examined 
at the FAA, Central Region, Office of the Regional Counsel, Room 
1558, 601 E. 12th Street, Kansas City, Missouri 64106.
    (f) The inspection, replacement, and modifications required by 
this AD shall be done in accordance with Pilatus Britten-Norman 
Service Bulletin No. BN-2/SB.229, dated October 17, 1996, or Pilatus 
Britten-Norman Service Bulletin No. BN-2/SB.228, Issue 2, dated 
January 17, 1996.
    (1) The incorporation by reference of Pilatus Britten-Norman 
Service Bulletin No. BN-2/SB.228, Issue 2, dated January 17, 1996, 
was approved previously by the Director of the Federal Register as 
of March 23, 1997 (62 FR 4909, February 3, 1997).
    (2) The incorporation by reference of Pilatus Britten-Norman 
Service Bulletin No. BN-2/SB.229, dated October 17, 1996, 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 Pilatus 
Britten-Norman. Copies may be inspected at the FAA, Central Region, 
Office of the Regional Counsel, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri, or at the Office of the Federal Register, 800 
North Capitol Street, NW, suite 700, Washington, DC.

    Note 4: The subject of this AD is addressed in British AD 007-
10-96, not dated.

    (g) This amendment becomes effective on October 12, 1998.

    Issued in Kansas City, Missouri, on August 18, 1998.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-22822 Filed 8-26-98; 8:45 am]
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