0.. 

Ronald J . Hinderberger Hie Boeing Company 

Lead Administrator P.O. Box 3707 MC 67-LR 

Delegated Compliance Org. Seattle, WA 98124-2207 

Commercial Airplanes 

DEC 1 6 2010 BDCO-10-053 84 

U.S. Department of Transportation 

Docket Management System 

1200 New Jersey Avenue, SE 

West Building Ground Floor, Room W12-140 

Washington, D.C. 20590 

Subject: Petition for Exemption from Title 14 Code of 

Federal Regulations section 25.1309(c) and 

25.1305(c)(6) at Amendment 25.120 with 

Respect to Crew Annunciation of the Status of 

Fuel System Components 

Model: 747-8F, 747-8 

The Boeing Company respectfully submits this petition for exemption from 

specific aspects of Title 14 Code of Federal Regulations Section 25.1309(c) and 

25.1305(c)(6) at Amendment 25.120 for a limited number of General Electric 

(GE) GEnx-2B powered 747-8F and 747-8 airplanes as described in the summary 

below. The enclosure to this letter provides the details of the petition in 

accordance with Title 14 Code of Federal Regulations Section 11.81. The 

following summary is provided for the Federal Register in accordance with 14 

CFR Section 11.81(f). 

Summary for Federal Register 

Petitioner: The Boeing Company. 

Section of 14 CFR Affected: Section 25.1309(c) and 25.1305(c)(6). 

Description of Relief Being Sought: 

Boeing is requesting relief from frill compliance to Section 25.1309(c) and 

25.1305(c)(6) for the General Electric (GE) GEnx-2B powered 747-8F and 747-8 

airplanes for the unambiguous and timely indication to the flight crew to alert 

them of an anticipated friel system contamination. If granted, this exemption will 

allow sufficient time for Boeing to develop, certify and incorporate into 

production a new alerting system this is fully compliant with Section 25.1309(c) 

and 25.1305(c)(6). The exemption would allow relief from the requirement in 

Section 25.1309(c) and 25.1305(c)(6) to provide indication to the crew of 

anticipated friel system contamination for General Electric GEnx-2B powered 

747-8F and 747-8 airplanes delivered up to June 30, 2014 and December 31, 

2018 for retrofit incorporation. 
( ^ Page 2 

Docket Management System 

BDCO-10-053 84 

Very truly yours, 

> /Christine Thompson 

"^Lead Project Administrator, Development Projects 

(425) 266-6572, MC 03-56 

FAX: (425)294-9340 

Enclosure: Petition for Exemption from 14 CFR 25.1309(c) and 

25.1305(c)(6) at Amdt. 25-120 

cc 

Name 

Ali Bahrami 

Gary Oltman 

Sue Lucier 

Jon Regimbal 

Henry Wildegans 

Henk Pruis 

Letter 

EDT 

EDT 

EDT 

EDT 

EDT 

EDT 

Enclosures 

EDT 

EDT 

EDT 

EDT 

EDT 

EDT 

Comments 

ANM-IOOS 

ANM-102S 

ANM-140S 

ANM-140S 

EASA Panel 0 

EASA Panel 7 
Enclosure to BDCO-10-05384 

Page 1 of 5 

Petition for Exemption from 14 CFR 25.1305(c)(6) and 25.1309(c) Amendment 25-120 for 

General Electric GEnx-2B Powered 747-8 and 747-8F Airplane Minor IVIodels, FAA 

Project Numbers PS05-0211 and PS05-0212 

Name and Address of the Petitioner 

CM. Thompson, Manager, Lead Project Administrator, Development Projects 

The Boeing Company, 

PO Box 3707, 

Seattle, Washington, 98124 

B. Section of the Code of Federal Regulations (CFRs) that are affected 

As provided for in 14 CFR 11.61(b), Boeing hereby petitions for exemption to the 

following CFRs: 

Reaulation 

14 CFR 25. 

1305(c)(6) 

14 CFR 

25.1309(c) 

At 

Amendment 

120 

120 

Which Requires 

(c) For turbine engine-powered airplanes. In addition 

to the powerplant instruments required by paragraph 

(a) of this section, the following powerplant 

instruments are required: 

(6) An indicator for the fuel strainer or filter required by 

§25.997 to indicate the occurrence of contamination of 

the strainer or filter before it reaches the capacity 

established in accordance with §25.997(d). 

(c) Warning information must be provided to alert the 

crew to unsafe system operating conditions, and to 

enable them to take appropriate corrective action. 

Systems, controls, and associated monitoring and 

warning means must be designed to minimize crew 

errors which could create additional hazards. 
Enclosure to BDCO-10-05384 

Page 2 of 5 

The extent of relief being sought 

Regulation 

14 CFR 

25.1305(c)(6) 

and 25.1309(c) 

Amendment 120 

Requires: 

For the GEnx2B fuel system 

to comply with 

14 CFR 

25.1309(c), an 

unambiguous 

and timely 

indication to 

the flight crew 

is required to 

alert them of 

an anticipated 

fuel system 

contamination 

that could clog 

the fuel 

system, or 

could 

significantly 

delay the 

indication 

required by 14 

CFR 

25.1305(c)(6) 

during gross 

contamination 

of the airplane 

fuel system. 

The purpose of 

this indication 

is to enable the 

flight crew to 

take 

appropriate 

corrective 

action. 

Relief is necessary because: 

The 747-8 and 747-8F / GEnx-2B engines will be 

some of the first General Electric engines to 

incorporate a method to detect gross fuel system 

contamination. The FAA only recently provided 

guidance regarding what is needed to show 

compliance to §25.1305(c)(6) and §25.1309(c) for 

indication of gross fuel contamination. Therefore, 

it would create a significant burden if Boeing were 

now required to incorporate this new gross fuel 

system contamination indication(s) on the first 

production 747-8/-8F airplanes. 

For the 747-8/-8F fuel systems to comply with 

§25.1309(c), an unambiguous and timely 

indication to the flight crew is required in the event 

that multiple engines on the same flight are 

subjected to a fuel filter impending bypass 

condition. Further, to comply with §25.1309(c), 

the flight crew must be alerted of anticipated fuel 

system contamination that could clog the fuel 

system ahead of the engine fuel filter, or that 

could significantly delay the indication required by 

§25.1305(c)(6) during gross contamination of the 

airplane fuel system. The purpose of this 

indication is to enable the flight crew to take 

appropriate corrective action. 

With this petition for exemption, Boeing is 

requesting relief for a limited number of 747-8F 

and 747-8 airplanes to allow sufficient time to 

develop, validate, certify and incorporate into 

production a new compliant gross fuel system 

contamination indication(s). Following 

incorporation of the compliant indication into 

production airplanes, Boeing will issue a service 

bulletin that recommends all airplanes delivered 

under this time limited exemption be retrofitted. 

Description of relief sought: The requested timelimited exemption will allow the Boeing Models 

747-8F and 747-8 relief from the requirement of 

§25.1305(c)(6) and 25.1309(c) for an 

unambiguous and timely indication to the flight 

crew of gross fuel system contamination. 
Enclosure to BDCO-10-05384 

Page 3 of 5 

The relief sought is limited to those 747-8F and 

747-8 aircraft completed prior to the production 

incorporation of the compliant message. The 

production incorporation of the compliant 

message will first be accomplished by 30 June 

2014. A service bulletin will be available no later 

than 30 June 2014 such that all 747-8F and 747-8 

airplanes delivered under this exemption can 

order parts and install a compliant configuration. 

The Boeing service bulletin will recommend that 

all airplanes be retrofitted by 31 December 2018. 

Passenger and crew safety will not be appreciably 

affected by a grant of exemption in this case. The 

requested time-limited exemption will allow the 

Boeing Models 747-8F and 747-8 relief from the 

requirement for an unambiguous and timely 

indication to the flight crew of gross fuel system 

contamination. 

Description of the Issue 

The FAA recently clarified what is required to show compliance to §25.1309(c) and 

§25.1305(c)(6) for indication of gross fuel contamination. Given the advanced stage of the 

747-8F and 747-8/GEnx-2B programs relative to gaining basic amended type design 

certification, Boeing is requesting this time-limited exemption to implement a robust, reliable 

design and verification of the subject alerting. Boeing agrees that severe fuel system 

contamination can lead to undesirable engine effects, such as loss of thrust. 

The FAA has found the 747-8F and 747-8 /GEnx-2B design to be non-compliant to §25. 

1309(c) and §25.1305(c)(6) for this issue. This FAA position is based on the lack of an 

unambiguous and timely annunciation to the flight crews of gross contamination of the airplane 

fuel supply. The engine fuel indication system does not currently directly address the basic 

problem of gross fuel system contamination indication. 

Prior to the expiration of this time-limited exemption, Boeing intends to comply with these 

requirements by providing a flight deck indication of gross fuel system contamination using a 

sensor upstream of the main fuel filter. Additionally, Boeing will elevate the existing EICAS 

flight deck alert for a multiple-engine fuel filter impending bypass condition. 
Enclosure to BDCO-10-05384 

Page 4 of 5 

Statement of No Adverse Affect on Safety 

The GEnx-2B engine fuel system design allows for the greatest possible tolerance to gross 

fuel contamination. Excessive fuel system component blockage of the GEnx-2B engine does 

not limit fuel flow to the engine due to multiple bypasses in the design. 

The main fuel filter is sized for compliance to §33.67 and subsequently §25.997(d). The fuel 

strainer at the LP pump exit provides additional filtering capability for the system. The fuel 

strainer is sized to protect the heat exchangers and high pressure fuel pump gear stage from 

extreme / maintenance-induced contamination. The fuel strainer does not stop particles that 

are within the size range of expected contamination. This contamination is passed through 

the eductor pump and the heat exchangers to the filter. When the filter is exposed to 

contaminated fuel and debris accumulates to the point that it reaches impending blockage, an 

alert is provided to the flight deck via an advisory level message according to the requirements 

of §25.1305(c)(6). The GEnx-2B fuel system indications provide flight crew warning 

information that an unsafe operating condition may exist via the main fuel filter advisory-level 

messages. This alerting scheme provides an adequate level of safety for the airplanes 

affected by this exemption. This is the same fuel filter alerting on all Boeing production 

airplanes. 

The existing GEnx engine also incorporates a differential pressure sensor across the fuel 

strainer that under certain conditions provides EICAS Status messages and CMC messages 

for additional awareness beyond any previous GE powered airplane model. 

Service history studies conducted showed that the fuel strainer / filter architecture used on 

GE90, GE90-115B, CF6-6, CF6-50, CF6-80A, CF6-80C2, and CF6-80E engines (similar 

architecture of the GEnx-2B engine) have had no known IFSD or power interruption events 

attributed to clogging of components upstream of the main fuel filter. 

The proven service history of similar engine models, the maintenance actions defined to 

preclude the introduction of solid contamination into the fuel tanks and the existing flight deck 

messages and crew procedures from associated checklists provide an adequate level of 

safety for the airplanes affected by this exemption. 

Statement of Public Interest 

Granting this petition is in the public's interest because it would allow adequate time for Boeing 

and its supplier to develop an effective design solution to the requirement to add a flight deck 

indication of gross fuel system contamination that became applicable to the Model 747-8F and 

747-8 well after the airplane development program completed firm configuration. Conversely, 

if the requested relief is not granted the addition of the subject flight deck indication at this late 

stage of the airplane development program would lead to delays in the deliveries of Models 

747-8F and 747-8 airplanes. The public interest will be advanced by the grant of Exemption 

as it is in the best economic interest of the United States. Many 747-8F and 747-8 customers 

are overseas. Further delivery delays of the 747-8F and 747-8 are not in the interest of the 

public due to the potential negative impact to export sales, the balance-of-trade, the gross 

domestic product and economic health of the United States. 
Enclosure to BDCO-10-05384 

Page 5 of 5 

In addition, without adequate time to develop a robust solution, nuisance flight deck alerts inservice have the potential to reduce operational safety when flight crews are tasked to respond 

to false indications potentially resulting in unnecessary flight diversions, landing at airports that 

they are not familiar with, and conceivably, shutting down an engine unnecessarily. 

Availability of 747-8F and 747-8 airplanes with the GEnx-2B engines will reduce fuel burn and 

hence reduce emissions of carbon dioxide, reduce global emissions of NOx, and reduce 

operating costs of airlines. 

Request for Waiver of Publication 

The petitioner requests that this petition for exemption not be delayed by the public process, 

which includes publication of the subject petition, due to the fact that this exemption will not set 

a precedent. Boeing believes good cause exists to waive the publication and comment 

requirements of §11.85, §11.87, and §11.89. 

The 747-8F and 747-8 petition is being provided in a timely manner; however, due to the 

scheduled delivery of the first 747-8F being near the second quarter of the year 2011, a delay 

in processing of the Exemption could delay the entry into service. 

H. Privileges of this Exemption Outside the United States 

Per §11.81 (h), Boeing requests that the privileges of this Exemption be extended outside the 

United States. This extension of privileges is necessary for operations based within foreign 

countries having bilateral agreements with the United States accepting FAA 14 CFR Part 25 

as their ainworthiness standards for transport category aircraft. The 747-8F and 747-8 are 

intended for the global market place with a launch customer based in a country utilizing the 

United States ainA/orthiness standards. 

I. Conclusion 

The requested time-limited exemption will allow the Boeing Models 747-8F and 747-8 relief 

from the requirement of §25.1305(c)(6) and §25.1309(c) for an unambiguous and timely 

indication to the flight crew of gross fuel contamination. 

The relief sought is limited to those 747-8F and 747-8 aircraft completed prior to the 

production incorporation of the compliant message. The production incorporation of the 

compliant message will be accomplished by 30 June 2014 delivery and all subsequent 747-8F 

and 747-8 airplanes. The Boeing Service Bulletin will recommend that all 747-8F and 747-8 

airplanes delivered under this exemption be retrofitted by 31 December 2018.