Petition for Extension of Limitation fr om Exemption No. 10267, 10267A, and 10267B

The Boeing Company Douglas M. Lane, ODA Deputy Lead Administrator The Boeing Company

PO Box 3707 Seattle, Washington, 98124

Section of the Code of Federal Re gulations (CFRs) that are affected

Regulation At

Amendment Which Requires

14 CFR 25.1305(c)(6) 120 (c) For turbine engine-powered airplanes. In addition to the powerplant instrum ents required by paragraph (a) of this section, the following powerplant instruments are required:

(6) An indicator for the fuel st rainer or filter required by §25.997 to indicate the occurr ence of contamination of

the strainer or filter befo re it reaches the capacity established in accordance with §25.997(d).

14 CFR 25.1309(c) 120 (c) Warning information must be provided to alert the crew to unsafe system operat ing conditions, and to enable them to take appropr iate corrective action. Systems, controls, and associated monitoring and warning means must be desig ned to minimize crew

errors which could create additional hazards.The Original Extent of Relief Sought and Reason(s):

Regulation Requires: Relief is necessary because:

14 CFR 25.1305(c)(6)

and 25.1309(c)

Amendment

120 For the GEnx-2B fuel system to comply with § 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 § 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. The 747-8 and 747-8F / GEnx-2B engines will

be some of the first G eneral 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. Therefor e, 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 prior to Type

Certification.

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 engi nes 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 contaminati on 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 t he 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 i ssue a service bulletin that recommends all airplanes delivered under this Time-Limited Exemption be

retrofitted.Description of relief sought: 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 fu el system contamination.

The relief sought is limited to those 747-8F and 747-8 aircraft completed prior to the production incorporati on 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 Boei ng service bulletin will recommend that all airplanes be retrofitted by 31 December 2016.

Description of Issue

On 7 June 2013, FAA Time-Limited Exempti on No. 10267B was published (as amended from the original issuance on 19 May 2011, and Re vision A on 5 August 2011) granting operators of the Boeing Model 747-8F and 747-8 airplanes powered by General Electric GEnx-2B engines temporary relief from the flight deck i ndication requirements for indicating fuel system contamination. The grant of Exemption was from the requi rements of §25.1305(c)(6) and §25.1309(c) at Amendment 25-120, for airplanes fo r which an application for an airworthiness certificate is made prior to 30 June 2014.

Boeing seeks an extension to t he time-limited relief from full compliance to §25.1305(c)(6) and §25.1309(c) for the GEnx-2B powered 747-8 and 747-8F production airplanes, for the unambiguous and timely indication to the flight crew to alert them of an anticipated fuel system contamination event. If gr anted, this extension will allow sufficient time for Boeing to complete modifications of the new Main Fuel-O il Heat Exchanger differential pressure sensing system, which has demonstrated less than des ired reliability on production airplanes. The

extension would allow relief fo r airplanes for which an app lication for an airworthiness certificate is made prior to 31 March 2015 and 30 September 2017 for retrof it of the 747-8 and

747-8F fleet.Relief from the original schedule is necessary because: Boeing and GE worked together to design and cert ify a gross fuel cont amination indicating system compliant to §25.1305(c)(6) and §25. 1309(c), under ODA Project Number PS13- 0049. On 25 June 2014, 747-8 airplane RC035 was the first production delivery of the compliant design. GE Service Bulletin GEnx-2B S/B 79-0017 (18 June 2014) and Boeing Service Bulletin 747-73-2082 (13 June 2014) provide retrofit instruction to the operators.

However, findings during production engine pass-off testing at GE and pre-delivery production airplane testing at Boeing has shown that the new Main Fuel-Oil Heat Exchanger differential pressure sensing system is demonstr ating less than desired re liability. The root cause process will identify necessary hardwar e and/or software modifications to improve system reliability. Until this design is avail able, Boeing desires to limit the number of airplanes in the fleet with this unreliable s ensing system. The grant ing of the Exemption extension will allow time for Boeing and GE to develop, validate, and certify a reliable Main Fuel-Oil Heat Exchanger differential pressure sensing system for production and in-service airplanes.

Statement of No Adverse Affect on Safety Due to Schedule Extension

Boeing contends that the safety rationale provi ded in the original Petition for Exemption is not compromised by this extension. Additionally, the unam biguous EICAS Caution message (ENG FL FILT MULT) is provided to t he flight crew in the event that multiple engines on the same flight subjected to a fuel filter impending by pass condition remains

active.

Statement of Public Interest

Boeing asserts that the public interest stated in the original Petition for Exemption is still applicable to the r equested extension.

Request to Waive Publication and Comment

Boeing requests that the revisi on to the original Time-Limit ed Exemption not be delayed by the public process including publication of the subject petition as there were no previous public comments, and the conditions for grant of the original Exemption remain the same.

Privileges of this Exemption Outside the United States

Per §11.81(h), Boeing requests that the privilege s of this Exemption be extended outside the United States. This extension of privileges is necessary for operations based within foreign countries having bilateral agreem ents with the United States acce pting FAA 14 CFR Part 25 as their airworthiness standards for transpor t category aircraft. The 747-8F and 747-8 are intended for the global market place with a launc h customer based in a country utilizing the

United States airworthiness standards.Conclusion

Boeing requests an additional nine (9) month ext ension to allow suffici ent time for Boeing to complete modifications of the new Main Fuel-Oil Heat Ex changer differential pressure sensing system, which has demonstrated less than desired reliability on production airplanes. This would result in an Exem ption termination date of 31 March 2015 for airplanes that have not been issued an original ai rworthiness certificate prior to this date and 30 September 2017 for retrofit of the 747-8 and 747-8F fleet.

Summary to be Published in the Federal Register

PETITIONER: Boeing Commercial Airplanes

SECTION OF 14 CFR AFFECTED: §25.1305(c)(6) and §25.1309(c)

DESCRIPTION OF RELIEF SOUGHT: The Boeing Company has requested additional compliance time until 31 March 2015 (an additional 9 months) for airplanes that have not been issued an original airworthiness certif icate prior to this date and 30 September

2017 for retrofit of the 747-8 and 747-8F fl eet. This nine (9) month extension is requested in order to complete modification s of the new Main Fuel-Oil Heat Exchanger differential pressure sensing system to improve system reliability, compliant with §25.1305(c)(6) and §25.1309(c), for GEnx -2B powered 747-8/8F airplanes.