AFS-15-3961-E

January 5, 2016

 Exemption No. 14235

 Regulatory Docket No. FAA-2015-2370

Mr. Steven Bastas

Manager, Winter Operations

United Airlines

233 South Wacker Drive, 17th Floor

Chicago, IL 60606

Dear Mr. Bastas:

This letter is to inform you that we have granted your request for exemption. It transmits our 

decision, explains its basis, and gives you the conditions and limitations of the exemption, 

including the date it ends.

The Basis for Our Decision

By letter dated June 2, 2015, you petitioned the Federal Aviation Administration (FAA) on 

behalf of United Airlines, for an exemption from § 121.629(b) of Title 14, Code of Federal 

Regulations (14 CFR) to exempt United Airlines from the requirement that “no person may 

take off an aircraft when frost, ice, or snow is adhering to the wings,” if Boeing, the original 

equipment manufacturer (OEM) of the B-737-600, -700, -800, and -900/900ER Next 

Generation (NG) airplanes, has determined a safe zone within which cold soaked fuel frost 

(CSFF) is permissible; visibly marked the zone on the wing; and placed an appropriate 

limitation in the FAA-approved Airplane Flight Manual (AFM).

The FAA has determined that good cause exists for not publishing a summary of the petition 

in the Federal Register because the requested exemption would not set a precedent, and any 

delay in acting on this petition would be detrimental to United Airlines.

The FAA has issued a grant of exemption in circumstances similar in all material respects to 

those presented in your petition. In Grant of Exemption No. 13337 (copy enclosed), the FAA 

found that allowing Southwest Airlines to dispatch and takeoff B737-700 and -800 NG 

aircraft with CSFF within the limitations specified in the FAA-approved Boeing AFM 
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accompanied by the required training of associated personnel would not adversely affect 

safety. In addition, the FAA found that a grant would be in the public interest because it 

would decrease the environmental impact of using deicing fluids and would increase 

operational efficiency and effectiveness by allowing specified aircraft as defined by the 

Boeing analysis and written in the FAA-approved AFM limitations to dispatch and takeoff 

without having to remove CSFF from the delineated upper wing surfaces. Although 

Exemption No. 13337 applied only to the B737-700 and 800 NG aircraft, the FAA finds that 

its determination that a grant of exemption would not adversely affect safety also extends to 

the B737-600 and 900/900ER NG aircraft because Boeing’s safety analysis and the FAAapproved AFM also cover these series. 

Having reviewed your reasons for requesting an exemption, I find that—

• they do not differ materially from those presented by the petitioner in the enclosed Grant

of Exemption No. 13337;

• the reasons stated by the FAA for granting the enclosed Grant of Exemption No. 13337 

also apply to the situation you present; and 

• a grant of exemption is in the public interest.

Our Decision

Under the authority contained in 49 U.S.C. §§ 106 (f), 40113 and 44701, which the FAA 

Administrator has delegated to me, United Airlines is granted an exemption from § 

121.629(b) of Title 14, Code of Federal Regulations (14 CFR) to exempt United Airlines from 

the requirement that “no person may take off an aircraft when frost, ice, or snow is adhering to 

the wings,” if Boeing, the original equipment manufacturer (OEM) of the B-737-600, -700, -

800, and -900/900ER Next Generation (NG) airplanes, has determined a safe zone within 

which cold soaked fuel frost (CSFF) is permissible; visibly marked the zone on the wing; and 

placed an appropriate limitation in the FAA-approved Airplane Flight Manual (AFM). This 

exemption is subject to the conditions and limitations described below.

Conditions and Limitations:

1. The dispatch and takeoff with CSFF on upper wing surfaces only applies to United

Airlines Boeing 737-600, -700, -800, and -900/900ER NG aircraft as specified in the 

Boeing engineering and aeronautical analysis.

2. United Airlines will use and adhere to the revised Boeing AFM miscellaneous limitations 

for CSFF in all instances concerning CSFF.

3. This exemption does not relieve United Airlines from any other limitations or 

requirements with regards to deicing and anti-icing operations.

4. This exemption is provided and effective under the following conditions:
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a. The appropriate United Airlines operations manual contains the following limitations 

and conditions from the FAA approved B-737-600, -700, -800, and -900/900ER NG 

AFM: 

Takeoff with cold soaked fuel frost on the wing tank upper surfaces is not permitted if 

any of the following conditions are present:

1) The ambient air temperature is below +4 degrees C, +39 degrees fahrenheit.

2) The tank fuel temperature is below -16 degrees C, +3 degrees F.

3) There is cold soaked fuel frost on the wing tank upper surfaces that is beyond the 

lines defining the permissible cold soaked fuel frost area.

4) There is precipitation or visible moisture (rain, snow, drizzle, or fog with less than 

1 mile visibility).

b. FAA has approved United Airlines CSFF pilot training program and any assigned 

pilots must have been trained prior to applying CSFF exemption standards.

c. United Airlines must provide ground and operational training to all pilots and ground 

personnel to ensure each is able to clearly discern the applicability of the CSFF 

exemption requirements, to include identifying which United Airlines aircraft have the 

painted CSFF upper wing areas. The training must include recognition of those 

airplanes approved for CSFF exemption.

d. The pilot-in-command retains final authority for takeoff of a flight with CSFF. 

This exemption terminates on Janaury 31, 2018, unless sooner superseded or rescinded.

Sincerely,

Enclosure