[Federal Register: September 12, 2008 (Volume 73, Number 178)]
[Rules and Regulations]
[Page 52909-52911]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12se08-3]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2008-0967; Directorate Identifier 2008-NM-152-AD;
Amendment 39-15671; AD 2008-19-04]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 777-200 and -300 Series
Airplanes Equipped With Rolls-Royce Model RB211-TRENT 800 Series
Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
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SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Boeing Model 777-200 and -300 series airplanes. This AD requires
revising the airplane flight manual to include in-flight procedures for
pilots to follow in certain cold weather conditions and requires fuel
circulation procedures on the ground when certain conditions exist.
This AD results from a report of uncommanded reduction in thrust on
both engines because of reduced fuel flows. We are issuing this AD to
prevent ice from accumulating in the main tank fuel feed system, which,
when released, could result in a restriction in the engine fuel system.
Such a restriction could result in failure to achieve a commanded
thrust, and consequent forced landing of the airplane.
DATES: This AD is effective September 29, 2008.
We must receive comments on this AD by November 12, 2008.
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
Fax: 202-493-2251.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
Hand Delivery: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
Examining the AD Docket
You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the
[[Page 52910]]
Docket Management Facility between 9 a.m. and 5 p.m., Monday through
Friday, except Federal holidays. The AD docket contains this AD, the
regulatory evaluation, any comments received, and other information.
The street address for the Docket Office (telephone 800-647-5527) is in
the ADDRESSES section. Comments will be available in the AD docket
shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Margaret Langsted, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6500; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Discussion
On January 17, 2008, a Boeing Model 777-200 series airplane
equipped with Rolls-Royce Model RB211 TRENT 895-17 turbofan engines
crash landed short of the runway at London Heathrow Airport. During
final approach, the autothrottles commanded an increase in thrust from
both engines, and the engines initially responded. However, at a height
of about 720 feet above the ground, the thrust of the right engine
reduced, and approximately seven seconds later, the thrust on the left
engine reduced. The uncommanded reduction in thrust on both engines was
the result of reduced fuel flows. The engine control system detected
the reduced fuel flows and commanded increased thrust. However, there
was no appreciable change in the fuel flow to either engine, and the
airplane crash landed short of the runway.
The investigation determined that over a long period of low power
fuel flows and low fuel temperatures associated with cruise flight, ice
can accumulate in the main tank fuel feed system and then release as a
result of increased fuel flow when high thrust is commanded. When
released, the ice could create a restriction within the engine fuel
system. A restriction in the engine fuel system, if not corrected,
could result in failure to achieve a commanded thrust, and consequent
forced landing of the airplane.
All of the testing and research of this accident has been conducted
on Boeing Model 777-200 and -300 series airplanes, equipped with Rolls-
Royce Model RB211-TRENT 800 series engines. Initial review of 777 other
airplane engine combinations has not revealed the same vulnerability to
the identified unsafe condition.
FAA's Determination and Requirements of This AD
We are issuing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the(se) same type
design(s). This AD requires revising the Limitations section of the
airplane flight manual to include procedures for pilots to follow in
certain cold weather conditions and requires fuel circulation
procedures on the ground when certain conditions exist.
Paragraph (g) of the AD requires that the fuel circulation
procedures be accomplished by a certified mechanic. We are including
this requirement because of the complexity of the procedure. We
recognize that persons other than mechanics who are properly trained
might also be capable of accomplishing this procedure. Therefore, we
would be receptive to requests for approval of alternative methods of
compliance in accordance with paragraph (j) of the AD to allow others
to accomplish the procedure if the request includes training and
oversight provisions to ensure that the procedure is accomplished
properly.
Interim Action
We consider this proposed AD interim action. If final action is
later identified, we might consider further rulemaking then.
FAA's Justification and Determination of the Effective Date
Hazardous amounts of ice might accumulate within the main tank fuel
feed system under certain conditions, which, when released, could
result in a restriction in the engine fuel system. Such a restriction
could result in failure to achieve a commanded thrust, and consequent
forced landing of the airplane. We have determined that the loss of
engine thrust was likely due to ice accumulating in the main tank fuel
feed system during long exposure to cold fuel temperatures and low
power fuel flows. It is necessary to issue interim mitigating actions
in order to prevent an additional accident. Because of our requirement
to promote safe flight of civil aircraft and thus, the critical need to
assure the proper functioning of the main tank fuel feed system and the
short compliance time involved with this action, this AD must be issued
immediately.
Because an unsafe condition exists that requires the immediate
adoption of this AD, we find that notice and opportunity for prior
public comment hereon are impracticable and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety, and we did not provide you with notice and an opportunity to
provide your comments before it becomes effective. However, we invite
you to send any written data, views, or arguments about this AD. Send
your comments to an address listed under the ADDRESSES section. Include
``Docket No. FAA-2008-0967; Directorate Identifier 2008-NM-152-AD'' at
the beginning of your comments. We specifically invite comments on the
overall regulatory, economic, environmental, and energy aspects of this
AD. We will consider all comments received by the closing date and may
amend this AD because of those comments.
We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this AD.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. ``Subtitle VII: Aviation
Programs,'' describes in more detail the scope of the Agency's
authority.
We are issuing this rulemaking under the authority described in
``Subtitle VII, part A, subpart III, section 44701: General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
Regulatory Findings
This AD will not have federalism implications under Executive Order
13132. This AD will 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.
For the reasons discussed above, I certify that this AD:
[[Page 52911]]
(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.
You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
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]
0
2. The FAA amends Sec. 39.13 by adding the following new AD:
2008-19-04 Boeing: Amendment 39-15671. Docket No. FAA-2008-0967;
Directorate Identifier 2008-NM-152-AD.
Effective Date
(a) This airworthiness directive (AD) is effective September 29,
2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 777-200 and -300 series
airplanes, certificated in any category; equipped with Rolls-Royce
Model RB211-TRENT 800 series engines.
Unsafe Condition
(d) This AD results from a report of the uncommanded reduction
in thrust on both engines because of reduced fuel flows. We are
issuing this AD to prevent ice from accumulating in the main tank
fuel feed system, which, when released, could result in a
restriction in the engine fuel system. Such a restriction could
result in failure to achieve a commanded thrust, and consequent
forced landing of the airplane.
Compliance
(e) Comply with this AD within the compliance times specified,
unless already done.
Airplane Flight Manual (AFM) Revision
(f) Within 10 days after the effective date of this AD, revise
the Limitations section of the AFM to include the following
statement. This may be done by inserting a copy of this AD in the
AFM.
``On ground, after refueling, check fuel temperature if fuel
temperature indication is operative. If fuel temperature is colder
than 0 degrees C or if fuel temperature indication is inoperative,
verify that a record exists certifying that the approved fuel
circulation procedure was performed.
``Perform all step climbs using VNAV or maximum climb thrust.
``In flight, within 3 hours of top of descent, but not less than
15 minutes before top of descent, check fuel temperature. If fuel
temperature is colder than -10 degrees C, perform a step climb using
maximum climb thrust. If a step climb using maximum climb thrust
cannot be accomplished, verify cruise speed is set to 0.84 Mach or
less, and manually advance thrust levers to maximum (autothrottles
may be overridden). After reaching maximum climb thrust, hold for 10
seconds or until reaching 0.86 Mach, whichever occurs first. Check
engines to ensure they have achieved maximum climb thrust and
operate normally.''
Fuel Circulation Procedure
(g) As of 10 days after the effective date of this AD: If the
fuel temperature has not exceeded 0 degrees Celsius during the
ground turn, before further flight, using the main tank fuel boost
pumps, pump fuel through the fuel manifold using the high flow mode
for a minimum of one minute. A certified mechanic must do the fuel
circulation procedure required by this paragraph using a method
approved by the Manager, Seattle Aircraft Certification Office
(ACO), FAA.
(h) Before further flight after accomplishing the action
required by paragraph (g) of this AD, make a record in which the
person accomplishing the procedure certifies that it was
accomplished in accordance with the approved method, and provide the
record to the flightcrew. Under the provisions of the Paperwork
Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and
Budget (OMB) has approved the information collection requirements
contained in this AD and has assigned OMB Control Number 2120-0056.
Special Flight Permit
(i) Special flight permits, as described in section 21.197 and
section 21.199 of the Federal Aviation Regulations (14 CFR 21.197
and 21.199), are not allowed.
Alternative Methods of Compliance (AMOCs)
(j)(1) The Manager, Seattle ACO, FAA, ATTN: Margaret Langsted,
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle ACO,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6500; fax (425) 917-6590; has the authority to approve
AMOCs for this AD, if requested using the procedures found in 14 CFR
39.19.
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your appropriate principal inspector (PI) in the FAA
Flight Standards District Office (FSDO), or lacking a PI, your local
FSDO.
Material Incorporated by Reference
(k) None.
Issued in Renton, Washington, on September 5, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-21138 Filed 9-11-08; 8:45 am]
BILLING CODE 4910-13-P