Exemption No. 10186

UNITED STATES OF 4MERICA DEPARTMENT OF TRANSPORTATION

, FEDERAL AVIATION ADMINISTRATION RENTON, WASHINGTON 98057-3356 I

Inthe matter ofthe petition of The Boeing Company for an exemption from 

### §26.35 ofTitle 14, Code ofFederal Regulations Regulatory Docket No. FAA-20IO-0905

GRANT OF EXEMiTiON By letter 7-7EI W-RlCIO-071, dated September 1,2010, Mr. Robert I. Carlson, AEW&C Certification Manager, The Boeing Company, 20403 68:1hAvenue South, 18-26 Building 1sl Floor MC: 84-08, Kent, Washington, 98.032,petitio~ed the Federal Aviation Administration (FAA) for anexemption from §26.35 ofTitle 14,Code ofFederal Regulations (14 CFR). This exemption is requested for Boeing Model 737~700 airpl~nes converted to Airborne Early Warning & Control (AEW&C) military airplanes inaccprdance with Supplemental Type Certificate (STC) ST01999SE. Part 26, subpart D, requirements are related to airplane fuel tank flanunability. The petitioner requests relief from the following regtdation: Section 26.35 Changes to type certificates affLting fuel tank flammability, which requires flammability exposure analyses, assessrhents to determine ifcritical design configuration control limitations are compromisbd, and the development ofdesign changes and service instructions. The petitioner supports its request with the following. The following information is quoted from The Boeing Company's petition with minor revisions for clarity. The complete petition may be found inthe Department ofTransportation's Federal Document Management System, Docket No. FAA~20I0-0905. Extent ofRelief Requested (14 CFR 11.81(e)): I The relief requested extends across new installa~ons associated with the AEW&C modifications as documented in STC ST01999SE and relief from the entire content of 14CFR 26.35.Why This Exemption Would Benefit the Public Interest (14 CFR 11.81(d)):

Granting this exemption will benefit the public interest by freeing up valuable FAA resources no longer required to evaluate and approve any enhanced instructions for continued airworthiness, asweUas design modifications and associated compliance data submittals to support these rule changes, particularly when no operators will be required to incorporate them. Why This Exemption Would Not Adversely Affect Public Safety (14 CFR 11.81(e)): Public safety will not be adversely affected because the Model 737-700 AEW&C is a military airplane that will notbe operated for commercial passenger transportation or compensation for hire. Further, it iscost prohibitive to reconfigure an airplane for such use after 

### ithas been converted to an AEW&C military airplane, making 

### ithigWyunlikely to ever be operated under part 121, 125, or 129. Summary for Publication inthe Federal Register (14 eFR II.8Iill); The petitioner seeks exemption from the requirements of 14CFR 26.35 forModel 737-700 airplanes that have incorporated the AEW&C modification, on the basis that these airplanes are not subjected to anoperational rule that would require an update of their maintenance programs. These airplanes arb not currently operated commercially within or outside the United States, and they arelnot expected to be inthe future. Federal Register publication A summary ofthe petition was published inthe Federal Register onNovember 24, 2010 (75 FR 71793). No comments were received regarding the exemption request. The FAA's analysis The FAA has developed criteria toconsider when deciding whether to grant or deny adesign approval holder's (DAH) petition for exemption from part 26 requirements. These criteria were meant as a general guide to making decisions about sudh requests and were not developed for any specific request. The FAA uses these criteria as a ~tarting point for making its decision. However, other factors may also beconsidered before ~final decision ismade on any particular exemption request. The criteria are illustrated inthe table that follows.

2The determination ofwhether an airplane isoperating under part 121, 125, or 129(N-registered)

isbased on whether that particular aiIplane is listed on an air carrier's Operations Specifications. The rationaJe behind the criteria contained inthe table above isthis: The rule requires DAHs to develop data for use by operators. Ifthere are no operators for aparticular airplane who are required by the rules to use such data, itwould be apoor use ofresources for the DAH to develop it. Therefore, itwould benefit both the DAH ahd the public as awhole to spend resources on more important safety issues rather than on developing data that will not be used. Inaddition, granting such anexemption would not adversely affect safety because there are no airplanes that would be required to incorporate the data, nor is itlikely that there will be any in the future. The FAA has reviewed The Boeing Company's request and has determined that granting this exemption would not have an adverse effect on public safety and would be in the public interest based on the following information: The FAA notes that Boeing Model 737-700 airplanes modified inaccordance with STC ST01999SE have been heavily modified to convert them to AEW&C airplanes for military use, and that they are not used forcommercial passenger transportation or compensation for hire. The petitioner also slated that the Model 737-700 AEW&C military airplane has been specially designed and configured formilitary operations under exclusive authority ofthe military airworthiness authority ofthe customer's country. Upon delivery, each airplane isremoved from the FAA registry. No airplanes are operating, or expected to operate inthe future, under parts 121, 125, or 129. The FAA finds that, since Model 737-700 AEW&C military airplane is used only in military applications, there is no FAA operating requirement to install the flammability reduction means orto keep itoperational ifalready installed. As aresult, Boeing Model 737-700 airplanes converted to AEW&C military airplanes in accordance with STC ST01999SE meet the baseline exemption criteria forpart 26. There are 110 other factors to be considered regarding The Boeing Company's petition for exemption. Additional information This exemption grants relief toThe Boeing Company from having to meet the airworthiness requirements of §26.35. This exemption docs not grant relief from the related operational requirements contained in §§ 121.1117, 125.509, and 129.117. Should aperson choose to operate aModel 737-700 AEW&C military airplane under part 121, 125, or 129beyond the operational compliance deadlines as stated in 

### §§ 121.1117, 125.509, and 129.117, that person will berequired tocomply with those operational requirements. In addition, this exemption does not provide any relief from part 25 requirements determined to be applicable when developing acertification basis in accordance with §21.101.

4The FAA'5decision

In consideration ofthe foregoing, Ifind that agrant of~xemPtion is inthe public interest. Therefore, pursuant to the authority contained in49 U.S.C. §§ 40113 and44701, delegated to me by the Administrator, The Boeing Company ishereby ~ranted anexemption from § 26.35 for STC STO1999SE. The limitations and conditions section of STC STO1999SE must listthis exemption and state that:

• compliance with §26.35 has not been demonstrated, and

• §§ 121.1117, 125.509, and 129.117 require that a Flammability Impact Mitigation Means be installed by the compliance times specified inthose regulations, ifrequired by §26.35. Issued in Renton, Washington, on 

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. ~-SUZanneMasterson Acting Manager, Transport Airplane Directorate Aircraft Certification Service

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