[Federal Register Volume 65, Number 198 (Thursday, October 12, 2000)]
[Proposed Rules]
[Pages 60593-60595]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-26094]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-144-AD]
RIN 2120-AA64


Airworthiness Directives; Gulfstream Model G-1159A (G-III) 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 certain Gulfstream Model G-1159A 
(G-III) series airplanes. This proposal would require modification of 
the master caution panel by installing an additional legend labeled 
``BATT ON BUS'' and associated wiring to indicate when the airplane 
batteries are powering the direct current (DC) essential bus. This 
action is necessary to ensure that the flight crew is aware that an 
electrical system failure has occurred and that the main airplane 
batteries are powering the essential DC bus. If the flight crew is 
unaware of this situation, action to stop the depletion of the airplane 
batteries will not be taken and critical equipment, such as 
communications and navigation equipment, could fail. This action is 
intended to address the identified unsafe condition.

DATES: Comments must be received by November 27, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-144-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. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-144-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Gulfstream Aerospace Corporation, P.O. Box 2206, M/S D-
10, Savannah, Georgia 31402-9980. This information may be examined at 
the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, Atlanta Aircraft Certification Office, One 
Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia.

FOR FURTHER INFORMATION CONTACT: Neil Berryman, Aerospace Engineer, 
Systems and Flight Test Branch, ACE-116A, FAA, Atlanta Aircraft 
Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 
450, Atlanta, Georgia 30349; telephone (770) 703-6066; fax (770) 703-
6097.

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.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a

[[Page 60594]]

request to change the service bulletin reference as two separate 
issues.
     For each issue, state what specific change to the proposed 
AD is being requested.
     Include justification (e.g., reasons or data) for each 
request.
    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 2000-NM-144-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-114, Attention: Rules 
Docket No. 2000-NM-144-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    Power to vital systems (such as aircraft flight displays, 
communication and navigation equipment, and fire extinguishing systems) 
is provided through the direct current (DC) essential bus. In the event 
of a problem with the power supply, the bus will automatically switch 
to battery power to keep these vital systems operating. Operation on 
battery power is for a short time and is intended only to allow time to 
land the airplane.
    Following a problem with the power supply to the DC essential bus, 
the flight crew may not be aware of the switch to battery power or the 
subsequent depletion of the batteries, because the relevant caution 
lights are located on the overhead instrument panel and are not in the 
primary line-of-sight of the flight crew. The FAA has one report of a 
loss of electrical power to the DC essential bus being undetected by a 
Gulfstream G-IV flight crew, because they did not see the caution 
light. The DC essential bus on certain Model G-IV series airplanes is 
almost identical to that on the affected Model G-III series airplanes. 
Therefore, those Model G-III series airplanes may be subject to the 
same unsafe condition revealed on the Model G-IV series airplanes.
    If the flight crew could not see the caution light, the flight crew 
could be unaware that an electrical system failure has occurred and 
that the airplane main batteries were powering the essential DC bus. If 
the flight crew were unaware of this situation, action to stop the 
depletion of the airplane batteries would not be taken and critical 
equipment, such as communications and navigation equipment, could fail.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Gulfstream Customer Bulletin No. 
149, dated March 23, 1999, which describes procedures for adding an 
additional legend to the master caution panel in the primary view of 
the flight crew to inform them when batteries are powering the DC 
essential bus. The customer bulletin also describes modification of 
wiring in the pilot's and copilot's junction boxes, the auxiliary power 
relay box, and the power distribution box. Gulfstream Customer Bulletin 
No. 149, dated March 23, 1999, references Gulfstream Aircraft Service 
Change No. 294, dated February 3, 1999, as the appropriate source of 
service information for accomplishment of the modification. 
Accomplishment of the actions specified in the customer bulletin and 
aircraft service change is intended to adequately address the 
identified unsafe condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require accomplishment of the actions specified in 
the Gulfstream customer bulletin and aircraft service change described 
previously, except as discussed below.

Differences Between the Proposal and the Customer Bulletin

    Operators should note that, although Customer Bulletin No. 149 
recommends accomplishing the modification within 24 months after the 
release of the customer bulletin, the FAA has determined that an 
interval of 24 months would not address the identified unsafe condition 
in a timely manner. In developing an appropriate compliance time for 
this proposed AD, the FAA considered not only the manufacturer's 
recommendation, but also the degree of urgency associated with 
addressing the subject unsafe condition and the average utilization of 
the affected fleet. In light of these factors, the FAA finds a 12-month 
compliance time for initiating the proposed actions to be warranted, in 
that it represents an appropriate interval of time allowable for 
affected airplanes to continue to operate without compromising safety.

Cost Impact

    There are approximately 198 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 144 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
55 work hours per airplane to accomplish the proposed modification, and 
that the average labor rate is $60 per work hour. Required parts would 
cost approximately $1,587 per airplane. Based on these figures, the 
cost impact of the proposed AD on U.S. operators is estimated to be 
$703,728, or $4,887 per airplane.
    The cost impact figure discussed above is 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 proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific actions actually required by the AD. 
These figures typically do not include incidental costs, such as the 
time required to gain access and close up, planning time, or time 
necessitated by other administrative actions.

Regulatory Impact

    The regulations proposed herein would not have a substantial direct 
effect 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, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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

[[Page 60595]]

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:

Gulfstream Aerospace Corporation: Docket 2000-NM-144-AD.

    Applicability: Model G-1159A (G-III) series airplanes, serial 
numbers 357 and 402 through 498 inclusive, 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 the flight crew from being unaware that an electrical 
system failure has occurred and that the airplane main batteries are 
powering the direct current (DC) essential bus, accomplish the 
following:
    (a) Within 12 months after the effective date of this AD, modify 
the wiring in the pilot's and co-pilot's junction boxes, the 
auxiliary power relay box, the power distribution box, and the 
master caution panel, in accordance with Gulfstream Customer 
Bulletin No. 149, dated March 23, 1999, and Gulfstream Aircraft 
Service Change No. 294, dated February 3, 1999.

Alternative Methods of Compliance

    (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, Atlanta Aircraft Certification 
Office (ACO), FAA. Operators shall submit their requests through an 
appropriate FAA Principal Maintenance Inspector, who may add 
comments and then send it to the Manager, Atlanta ACO.

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

Special Flight Permits

    (c) 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.

    Issued in Renton, Washington, on October 4, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-26094 Filed 10-11-00; 8:45 am]
BILLING CODE 4910-13-P