[Federal Register Volume 60, Number 198 (Friday, October 13, 1995)]
[Proposed Rules]
[Pages 53308-53310]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-25440]



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[[Page 53309]]



DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-CE-13-AD]


Airworthiness Directives; Fairchild Aircraft SA226 and SA227 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to revise Airworthiness Directive (AD) 
95-17-09, which requires relocating the left-hand (LH) and right-hand 
(RH) essential bus current limiters (225 amp) to the battery bus (main 
bus tie) on certain Fairchild Aircraft SA226 and SA227 series 
airplanes. The FAA has determined that the applicability of the current 
AD should be changed to reflect a different serial number range and 
model designation of certain SA227 series airplanes. The proposed 
action would retain the essential bus current limiter relocations 
required by AD 95-17-09, and would revise the Applicability section of 
that AD. The actions specified by the proposed AD are intended to 
prevent failure of the LH and RH essential bus when engine failure 
results in a blown generator current limiter, which could result in 
loss of airplane electrical power.

DATES: Comments must be received on or before December 11, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 95-CE-13-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 Field Support Engineering, Fairchild Aircraft, P.O. Box 790490, 
San Antonio, Texas 78279-0490; telephone (210) 824-9421; facsimile 
(210) 820-8609. This information also may be examined at the Rules 
Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. George R. Hash, Aerospace 
Engineer, FAA, Airplane Certification Office, 2601 Meacham Boulevard, 
Fort Worth, Texas 76193-0150; telephone (817) 222-5134; facsimile (817) 
222-5959.

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. 95-CE-13-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. 95-CE-13-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Discussion

    On August 10, 1995, the FAA issued AD 95-17-09, Amendment 39-9339 
(60 FR 43361, August 21, 1995), to require relocating the left-hand 
(LH) and right-hand (RH) essential bus current limiters (225 amp) to 
the battery bus (main bus tie) on certain Fairchild Aircraft SA226 and 
SA227 series airplanes. AD 95-17-09 specifies accomplishment of the 
relocations in accordance with Fairchild Aircraft Engineering Kit 
Drawing 27K82376, ``Current Limiter Rebusing Kit,'' as referenced in 
Fairchild Service Bulletin (SB) 226-24-034, SB 227-24-015, and SB CC7-
24-002, all Issued: September 29, 1994.
    A safety recommendation detailing potential electrical failure 
problems on Fairchild SA226 and SA227 series airplanes prompted AD 95-
17-09. Flight simulation revealed that electrical power loss could 
occur on the affected airplanes because of failure of the LH essential 
bus. Switching delays between the left and right side electrical 
systems result in left generator motor action, which could then cause 
the left side current limiter to open. This would result in failure of 
the left essential bus, which will result in loss of alternating 
current (AC) power to the primary attitude indicator and the lighting 
for the standby attitude indicator.
    The FAA has determined that AD 95-17-09 contains the following 
errors:

--Incorrect serial numbers for the Fairchild Aircraft Models SA227-AC, 
SA227-AT, SA227-BC, and SA227-TT airplanes in the Applicability 
section; and
--Incorrect designation for Model SA227-AC as SA227-AD in paragraph (a) 
of AD 95-17-09.

    After examining all available information related to the subject 
discussed above, the FAA has determined that further AD action should 
be taken to prevent failure of the LH and RH essential bus when engine 
failure results in a blown generator current limiter, which could 
result in loss of airplane electrical power.
    Since an unsafe condition has been identified that is likely to 
exist or develop in other Fairchild Aircraft SA226 and SA227 series 
airplanes of the same type design, this AD requires the same relocation 
of the left-hand and right hand essential bus current limiters as is 
contained in AD 95-17-09, and revises the Applicability section to 
reflect the serial number correction and model designation correction 
in paragraph (a) of that AD as previously described.
    The FAA estimates that 876 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 4 
workhours per airplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts cost 
approximately $98 per airplane. Based on these figures, the total cost 
impact of the proposed AD on U.S. operators is estimated to be $296,088 
($338 per airplane). This figure is based on the assumption that no 
affected airplane owner/operator has incorporated the proposed 
modification. Fairchild Aircraft has informed the FAA that parts have 
not been distributed to any owner/operator of the affected airplanes.
    The proposed action would only correct a model designation and 
certain serial numbers of certain SA227 series airplanes that are 
affected by AD 95-17-09. The cost impact upon the public specified in 
the proposed AD is exactly the same as that currently required by AD 
95-17-09.
    The regulations proposed herein would not have substantial direct 
effects on the States, on the relationship 

[[Page 53310]]
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. 106(g); 40101, 40113, 44701.


Sec.  39.13  [Amended]

    2. Section 39.13 is amended by removing Amendment 39-9339 (60 FR 
43361, August 21, 1995), and by adding a new airworthiness directive 
(AD) to read as follows:

Fairchild Aircraft: Docket No. 95-CE-13-AD. Revises AD 95-17-09; 
Amendment 39-9339.

    Applicability: The following model and serial number airplanes 
that utilize a direct current (DC) generator, certificated in any 
category.

------------------------------------------------------------------------
                  Models                             Serial Nos.        
------------------------------------------------------------------------
SA226-T, SA226-AT, SA226-TC, and SA226-     All.                        
 T(B).                                                                  
SA227-AC, SA227-AT, SA227-BC, and SA227-TT  420 through 783, and 785    
                                             through 789.               
SA227-CC and SA227-DC.....................  784, and 790 through 883.   
------------------------------------------------------------------------

    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 (c) 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 2,000 hours time-in-service 
after the effective date of this AD, unless already accomplished 
(compliance with AD 95-17-09).
    To prevent failure of the left hand (LH) and right hand (RH) 
essential bus when engine failure results in a blown generator 
current limiter, which could result in loss of airplane electrical 
power, accomplish the following:
    (a) Relocate the LH and RH essential bus current limiters (225 
amp) to the battery bus (main bus tie) in accordance with Fairchild 
Aircraft Engineering Kit Drawing 27K82376, ``Current Limiter 
Rebusing Kit,'' as referenced in the following service bulletins 
(SB):

------------------------------------------------------------------------
             SB                          Date            Models affected
------------------------------------------------------------------------
226-24-034..................  Sept. 29, 1994...........  All affected   
                                                          SA226 models. 
227-24-015..................  Sept. 29, 1994...........  SA227-AC, SA227-
                                                          AT, SA227-BC, 
                                                          and SA227-TT. 
CC7-24-002..................  Sept. 29, 1994...........  SA227-CC and   
                                                          SA227-DC.     
------------------------------------------------------------------------

    (b) 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.
    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Fort Worth Airplane Certification Office 
(ACO), FAA, 2601 Meacham Boulevard, Fort Worth, Texas 76193-0150. 
The request shall be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Fort Worth ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Fort Worth ACO.

    (d) All persons affected by this directive may obtain copies of 
the document referred to herein upon request to Fairchild Aircraft, 
P.O. Box 790490, San Antonio, Texas 78279-0490; 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.
    (e) This amendment revises AD 95-17-09, Amendment 39-9339.

    Issued in Kansas City, Missouri, on October 6, 1995.
Henry A. Armstrong,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-25440 Filed 10-12-95; 8:45 am]
BILLING CODE 4910-13-U