
[Federal Register Volume 76, Number 143 (Tuesday, July 26, 2011)]
[Rules and Regulations]
[Pages 44457-44458]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-18191]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 34

[Docket No. FAA-2011-0746]


Application of Regulations on Fuel Venting

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Policy determination.

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SUMMARY: This document advises the public of a recent decision by the 
Federal Aviation Administration (FAA) concerning the application of 
certain provisions of the regulations regarding fuel venting 
requirements.

DATES: We must receive your comments by August 25, 2011.

ADDRESSES: This is a notice of a policy determination only. You may 
send comments identified by Docket Number FAA-2011-0746 using any of 
the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the online instructions for sending your 
comments electronically.
     Mail: Send comments to Docket Operations, M-30; U.S. 
Department of Transportation, 1200 New Jersey Avenue, SE., Room W12-
140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to http://www.regulations.gov, including any personal 
information the commenter provides. Using the search function of the 
docket Web site, anyone can find and read the electronic form of all 
comments received into any FAA dockets, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov.
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov at any time. Follow the online instructions 
for accessing the docket or go to Docket Operations in Room W12-140 of 
the West Building Ground Floor at 1200 New Jersey Avenue, SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Curtis Holsclaw, Office of Environment 
and Energy (AEE-2), FAA, 800 Independence Ave., SW., Washington, DC 
20591; e-mail Curtis.holsclaw@faa.gov, facsimile (202) 267-5594, 
telephone (202) 267-3575.

SUPPLEMENTARY INFORMATION: Title 14 of the Code of Federal Regulations 
(14 CFR), part 34, Sec.  34.11 is the regulation that prohibits fuel 
venting, the intentional discharge to the atmosphere of fuel drained 
from fuel nozzle manifolds after engines are shut down. By its terms, 
the regulation does not apply to normal fuel seepage from shaft seals, 
joints, and fittings.
    During a recent aircraft certification, the FAA became aware of 
difficulties in applying the language of Sec.  34.11 to the newest 
designs of aircraft engines. The Boeing Models 747-8, 747-8F, and 787 
series airplanes incorporate new General Electric (GE) Model GEnx-2B 
and GEnx-1B engines, respectively. These GE engines include an advanced 
technology fuel system that significantly reduces fuel consumption and 
emissions. This technology incorporates the use of a larger, complex 
fuel manifold and a new fuel nozzle design that also uses check valves 
as an alternative to a fuel manifold drainage collection tank as a 
means to prevent release of fuel after shutdown. While this design 
reduces overall emissions, flight tests revealed an intermittent, 
inadvertent release of a small amount of

[[Page 44458]]

fuel after the engines were shut down. This release of fuel is caused 
by unexpected elevated fuel manifold pressures that result in the 
release of fuel from the fuel nozzles. Under certain atmospheric 
conditions this release of fuel results in a visible vapor. This event 
was not observed during the GEnx engine's certification testing under 
14 CFR part 33, but only after it was installed and operated on the 
subject airplanes.
    Following these observations, the FAA reconsidered how the 
provisions of Sec.  34.11 should be applied under the circumstances of 
these certifications. A review of the history of the section found that 
it was promulgated in 1973 in response to short-sighted environmental 
practices of the time, including the routine dumping of up to a gallon 
of raw fuel onto the ground after engines were shut down. The general 
prohibition in Sec.  34.11 is stated in the first sentence of that 
section, that ``[n]o fuel venting emissions shall be discharged into 
the atmosphere from any new or in-use aircraft gas turbine engine 
subject to the subpart.'' The second sentence appears to condition this 
prohibition, stating that ``[t]his paragraph is directed at the 
elimination of intentional discharge to the atmosphere of fuel drained 
from fuel nozzle manifolds after engines are shut down and does not 
apply to normal fuel seepage from shaft seals, joints, and fittings.'' 
The language of the second sentence presents a unique situation in 
aircraft certification by introducing the concept of intent, without 
clearly referencing where the intent attaches. The second sentence also 
specifies three locations where ``seepage'' is considered normal and 
acceptable.
    Historically, application of Sec.  34.11 has not been an issue. 
Aircraft engines designed since promulgation of the rule have not 
included any means by which fuel is collected and dispersed outside the 
engine after shutdown. The GEnx engines at issue do not release fuel 
from the three locations noted in the regulation--shaft seals, joints, 
or fittings. Nor does the amount of fuel or the manner in which it is 
being released rise to the level of historical fuel dumping that 
prompted the adoption of the regulation in 1973. Yet, small quantities 
of fuel (up to 5.5 ounces) are being released intermittently under 
certain conditions, and the fuel is being vaporized on contact with hot 
surfaces inside the engine, resulting in the visible fuel vapors that 
have been observed when they emit from either the inlet or exit plane 
of the engine.
    The new engines incorporate technological advances and 
environmental performance improvements that were never envisioned when 
the original regulation was adopted in 1973. These factors have made it 
more difficult to reconcile the design and function of these engines in 
a certification context with a 38-year-old regulation that was aimed at 
a different set of circumstances. Application of the current regulation 
has become less clear in this context.
    With the cooperation of the equipment manufacturers, the FAA 
investigated the safety and environmental effects of the fuel release 
and vaporization. The FAA consulted with the Environmental Protection 
Agency (EPA) on the local air quality impacts. While we were satisfied 
that no safety and minimal environmental effects are evident, we remain 
concerned about compliance with the intent of the current regulation, 
and the inability of the current regulation to be unambiguously applied 
to the certification situation.
    The FAA has determined that the best course of action is to allow 
the current certification of these engine/airframe combinations. The 
certification basis includes requirements that the manufacturers 
develop and install modifications that will eliminate these 
intermittent fuel releases and observed vapors that have been 
experienced during certification testing. These modifications will 
apply to newly manufactured airplanes by December 31, 2012, and in-use 
airplanes by December 31, 2014.
    The technological advances incorporated in these engines allow them 
to more than exceed the separate regulatory requirements for emissions 
that are the focus of current environmental compliance efforts. The FAA 
will re-examine the language of the fuel venting regulation and its 
application during certification to determine whether it needs to be 
changed to address issues associated with newer technologies. We may 
consult with the EPA on whether to propose changes to Sec.  34.11 and 
its companion regulation at 40 CFR 87.11. We will also consider whether 
more flexibility in application of the regulation is appropriate based 
on the experience gained during this certification. The decision to 
proceed with certification of the subject airframe/engine combinations 
is an effort to acknowledge the lack of clarity in the application of 
the regulation to the specific circumstances encountered. The 
requirement to modify the aircraft is intended to prevent any 
retrenchment from the original regulatory intent.

    Issued in Washington, DC, on July 14, 2011.
Lourdes Q. Maurice,
Executive Director, Office of Environment and Energy.
[FR Doc. 2011-18191 Filed 7-25-11; 8:45 am]
BILLING CODE 4910-13-P


