March 6, 2014

SUBMITTED ELECTRONICALLY TO: Federal Docket Management System, 

www.regulations.gov

U.S. Department of Transportation

Docket Operations

West Building, Room W12-140

1200 New Jersey Avenue, SE

Washington, D.C. 20590-0001

RE: International Aero Engines, LLC Petition for Reconsideration of Exemption Denial, 14 

CFR § 33.94(a)(1), Regulatory Docket No. FAA-2013-0815, Exemption No. 10914

Dear Ladies and Gentlemen:

Pursuant to 14 CFR § 11.101,

1 International Aero Engines, LLC (IAE, LLC) hereby petitions 

for reconsideration of the FAA’s January 9, 2014 denial of an exemption from 

§ 33.94(a)(1) for the PW1100G-JM Series Turbofan Engine.

The exemption would allow IAE, LLC to show that its engine is capable of containing 

damage without catching fire and without failure of its mounting attachments where the 

most critical fan blade fails at the blade platform (as more particularly defined in technical 

specifications) rather than at the outermost retention groove. This would result in the 

liberation of more than 80% of the fan blade which is more material than required by 

§ 33.94(a)(1) for the failure point in integrally-bladed rotors.

Legal basis for this request

Section 11.101 provides that a petitioner for reconsideration must, within 60 days after an 

exemption request is denied --

(a) Present a significant additional fact and explain why it was omitted from the original 

petition; 

(b) Establish that the FAA made an important factual error in denying the original 

petition; or

(c) Show that the FAA did not correctly interpret a law, regulation, or precedent. 

 1 All citations are to 14 CFR unless otherwise noted.

117 North Henry Street, Alexandria, VA 22314–2903

Telephone 703.299.0784 Fax 703.299.0254

www.potomac-law.com

Marshall S. Filler Direct Dial - 703.451.7393

Admitted in the District of Columbia and Virginia E-Mail - marshall.filler@potomac-law.com
U.S. Department of Transportation

Docket Operations

March 6, 2014

Page 2

RE: International Aero Engines, LLC Petition for Reconsideration of Exemption Denial, 

14 CFR § 33.94(a)(1), Regulatory Docket No. FAA-2013-0815, Exemption No. 10914

As further described below, IAE, LLC is submitting significant additional facts in accordance 

with § 11.101(a).

Summary of IAE, LLC Petition for Exemption

On September 12, 2013, IAE, LLC filed a petition for exemption from § 33.94(a)(1).2 In 

support of its request, IAE, LLC stated that the design characteristics of the PW1100G-JM 

geared turbofan engine are such that the most critical fan blade will not fail below the 

platform over the blade’s service life. In its petition IAE, LLC stated that the part 33 impact 

assessment and associated engineering data submitted to the FAA3 demonstrated that an 

exemption would not adversely affect safety and would provide an equivalent level of safety 

to that provided by the rule. 

IAE, LLC also stated that granting the petition is in the public interest because it would 

enable the company to design and manufacture an engine with a lighter fan case and 

accessory attachments, and an optimized flange joint design. This results in a lighter-weight 

engine relative to the engine thrust generated, which leads to (1) lower fuel burn, and (2) 

reduced emissions. IAE, LLC then provided specific figures to quantify the reduced fuel 

burn, reduced emissions, and cost savings – all of which constitute significant, tangible 

benefits to the public as a whole.

Summary of FAA Denial 

On January 9, 2014, the FAA denied IAE, LLC’s request for the following reasons. 

1. The petition for exemption stated that the fan blade will not fail below the platform 

over the service life of the blade, but did not provide technical data to establish that 

probability of failure to be at least equivalent to a failure rate of extremely improbable 

or less. Consequently, the petitioner has not shown that granting the exemption 

would not adversely affect safety or shown how the exemption would provide a level 

of safety at least equal to that provided by the rule or those established by the GE 

special conditions.

2. The yearly fuel savings per engine was incorrectly stated in the petition. The petition 

estimated a yearly fuel savings of 26,000 gallons per engine; however, this is the 20-

year fuel savings. The annual fuel savings per engine is 1,292 gallons, which is 

substantially less. Based on an estimated 1,500 flights per year, this fuel savings 

equates to approximately two gallons per flight.

 2 The petition was supplemented on September 26, 2013 to address international issues.

3 This privileged and confidential data was submitted directly to the Engine & Propeller Directorate for 

evaluation.
U.S. Department of Transportation

Docket Operations

March 6, 2014

Page 3

RE: International Aero Engines, LLC Petition for Reconsideration of Exemption Denial, 

14 CFR § 33.94(a)(1), Regulatory Docket No. FAA-2013-0815, Exemption No. 10914

Significant additional facts

Pursuant to § 11.101(a), IAE, LLC is submitting significant additional engineering 

information showing that the probability of the fan blade’s failure below the platform is 

extremely improbable or less. This confidential analysis will be submitted in confidence to 

the Engine & Propeller Directorate contemporaneously with the filing of this petition for 

reconsideration.

This detailed technical report provides evidence in the form of significant additional data, 

test results, and analyses which shows that the fan blade below platform fracture rate for 

the PW1100G-JM Series Turbofan Engine is extremely improbable (i.e., less than 1E-09 

per flight hour). This probability of fracture supports the conclusion that safety is not affected 

and the requested exemption to § 33.94(a)(1) would provide an equivalent level of safety to 

that provided by the rule. 

The fracture rate determination was based on a robust fault tree risk analysis that includes 

all below platform fracture mechanisms of the PW1100G-JM fan blade, including corrosion, 

low cycle fatigue, embedded flaws, high cycle fatigue, impact and overstress.

The data was not provided in the original submittal because § 33.94(a)(1) does not include

a probability analysis requirement. Although such a requirement was included in the GE 

special conditions4

, there was no indication in that document that this analysis had been 

performed before the special conditions were issued.

As the FAA correctly noted on page 7 of the Denial of Exemption, the 26,000-gallon figure is 

the 20-year fuel savings for each engine, not the per year fuel savings. However, the 

remaining figures for fuel consumption reduction (192.2 million gallons), cost savings ($517 

million), and reduced carbon dioxide emissions (2.7 billion pounds) are all accurate when 

the life of the engine program (i.e., 5000 engines entering into service between 2015 and 

2035) is considered in the aggregate. It is these aggregated public benefits – particularly 

the reduced carbon dioxide emissions – which support a finding that granting this petition is 

in the public interest.

In summary, granting this petition would allow the approval of a fan blade which results in 

less fuel burn, lower operating costs and reduced emissions. It would also be consistent 

with Congress’ desire to encourage the development of new aviation technology which is

clearly in the public interest.

 4 The special conditions were issued for the GEnx series, the GEnx-2B series and the GE90-75B/-85B/-

76B model turbofan engines.
U.S. Department of Transportation

Docket Operations

March 6, 2014

Page 4

RE: International Aero Engines, LLC Petition for Reconsideration of Exemption Denial, 

14 CFR § 33.94(a)(1), Regulatory Docket No. FAA-2013-0815, Exemption No. 10914

Good Cause Exists to Grant this Request without Further Notice and Comment

Section 11.87 lists four factors that the agency considers in deciding whether a petitioner 

has shown good cause for the FAA not to delay action on a petition for exemption. Those 

factors are set forth below in italics along with the company’s response in plain text:

(a) Whether granting the petition would set a precedent: The FAA has previously 

granted similar relief in the form of special conditions as referenced in this petition; 

therefore, this request would not set a precedent.

(b) Whether the relief requested is identical to exemptions previously granted: The 

requested relief is substantially similar to that previously granted through the special 

conditions process.

(c) Whether delaying action would adversely affect IAE, LLC: Delaying action for the 

notice and comment process will inject further delay and uncertainty into the 

certification process. IAE, LLC is planning to run another engine test in May and 

therefore requires a decision on its request as soon as possible.

(d) Whether the petition was filed in a timely manner: The petition for reconsideration is 

timely filed.

Summary of Petition for Reconsideration

In accordance with § 11.81(f), IAE, LLC offers the following summary suitable for publication 

in the Federal Register.

IAE, LLC petitions for reconsideration of the FAA’s January 9, 2014 denial of

an exemption from § 33.94(a)(1) for its engine model PW1100G-JM. The 

exemption would allow IAE, LLC to show that the engine is capable of 

containing damage without catching fire and without failure of its mounting 

attachments where the most critical fan blade fails at the fan blade platform 

rather than at the outermost retention groove. The petition for reconsideration 

is based on the submission of significant additional engineering information 

demonstrating that failure of the blade below the platform is extremely 

improbable.

Respectfully submitted,

Marshall S. Filler

Counsel for International Aero Engines, LLC

Attachment (submitted separately to the FAA)