Exemption No. 9999

UNITED STATES OF AMERICA DEPARTMENT OF TRANSPORTATION FEDERAL AVIAnON ADMINISTRA nON RENTON, WASHINGTON 98057·3356

In the matter ofthe petition of Airbus for an exemption from §25.562(b)(2) of Title 14,Code-ofFederal Regulations Regulatory Docket No. FAA·2009·I053

GRANT OF EXEMPTION By letter LR25 IOM09015452 ,dated April 2, 2009, Mssrs. Jean Francois Petit, Certification Manager, and Jelm~ClaudeNANCHE, A350 Chief Airworthiness Engineer, Airbus, 1Rond~ Point Maurice Bellante 31707 Blagnac Cedex, France, petitioned for exemption from § 25.562(b)(2), Title 14,Code afFederal Regulations (14 CFR), as amended by Amendment 25-64. The proposed exemption, ifgranted, would permit relief from the floor ~.'arpagetesting requirement for flight deck seats on Airbus Model A350 airplanes. The petitioner requests relief from the following regulations: Section 25.562(b)(2), Amendment 25~64,requires the floor tracks usedto attach the seat to the floor be misaligned with respect tothe adjacent seat tracks by atleast 10degrees vertically (i.e., out ofparallel) with onerolled 10degrees. The misaligmnent is used during the forward loading dynamic test condition and applies to all seats occupiable for takeoff and landing.

The petitioner supports its request with the following information: This information is quoted from Airbus' petition, with minor edits for darity. Airbus seeks exemption ham the requirement to demonstrate compliance by testing the flight deck seats. The reason Airbus seeks this relief isthat FAA hasdctemllned that such !csting is unnecessary. Since 1992 FAA has taken the

position (see, e.g. Docket 26649, Exemption Grant 5436 dated April 1, 1992) that ·there has not been aproblem with flight deck seat scparations due to floor buckling on narrow body and larger airplanes which have aminimum of 40 inches of frangible structure between the flight deck floor and the lower fuselage contour. The FAA now considers that requiring testing ofpilot seats with floor WalVagccarmot bejusti Red 011 Ilanow body and larger airplanes.' Since that position was first taken, FAA has granted numerous exemptions from the floor warpage testing requiremcnts for flight deck scats to both U.S. and nOI1- U.S. applicants. Airbus seeks the same relief that has been granted toother similarly situated applicants. (See, e.g., exemptions 6425, 6425A, 6600, 6819. 6887, and 6935, all granted to applicants seeking the same relief under similar circumstances_) Airbus submits that granting this exemption is inthe public interest because such action will:
I. Not adversely affect flight safety, as the FAA itselrhas stated; 2. Improve Ihe erricicllcy oftileAirbus A350; 3. Tend to reduce air transp0l1ation and aircargo fares rorall users; and 4. Reduce the cost ofthe aircraft to U.S. operators. FAA has analyzed past requests from numerous petitioners as noted above. These requests were similar inall material respects tothe request ofAirbus. Simply put, using FAA words (see Exemption 6887), 'Subsequent to the adoption ofthi5 requirement by Amendment 25-64, itwas detemlined that, although some cockpit floor dist0l1ions have occurred during accidents, there has not been aproblcm with night dec-kseat separations due to noor buckling on 'nanow body" and larger airplanes having al least 40 inches or frangible struclUre between the flight deck noor andthe extended lower fuselage contour [as does the A350]. Consequently, the 

## r:AAhas concluded that requiring the testing of flight deck seats under conditions of floor warpage cannot bejusti fied on airplanes ofthis minimum size. Although the A350 fuselage will be largely made ofCFRP [carbon fiber reinforced plastic], the nose section and 1110re especially the structure below the cockpit floor is mainly made ofaluminum alloy like 011 traditional metallic fusclages_ More specifically. circumferential frames, skin, nose landing gear bay box structure, and vertical rods are constructed ofaluminulll alloy materia!. The figure below shows the 40 lI1chreference orthe frangible structure between the night deck floor and the extended lower fuselage contour. Although aminor portion orthe skin within the 40 inch zone below the observer seats are made of CFRP, Ihis is nOIlrelevant compared 10the aluminum nose landing gear bay structure and vertical rods.

2Federal Register publication

The FAA determined that good cause existed for waiving the requirement forFederal Register publication. This ae-tionwill not set aprecedent, and we did not receive any comments on previous similar actions that were published inthe Federal Register.

The FAA's analysis The petitioner requests exemption from the requirement in §25.562(b)(2) to conduct dynamic testing with the scat tracks misaligned. This request is limited to seats on the flight deck. The petitioner notes that the FAA has previously granted numerous exemptions from this requirement. While such exemptions must bereviewed forprecedent, the factthat other exemptions have been granted does not ensure that further exemptions will be granted. The conditions and rationale must beestablished ineach case, inorder tojustify relief from arequirement. The petitioner's request forrelief from the requirement to misalign the seat tracks is limited to the Airbus Model A350 flight deck seats. These seats are individually mounted single scats with both floor and wall mounting, to accommodate both flightcrew and observers. Crew seats arc required to be fairly rigid inorder to withstand the pilot reaction forces from the flight controls. Wall mounted seats are generally not subject to floor misalignment requirements, no matter where installed, since they do not mount directly tothe floor. The FAA has reviewed the arguments presented by the petitioner and concluded that the service history ofnight deck scats on larger airplanes supports the petitioner's request and it isinthe interest ofthe public forthe reasons given bythe petitioner. The A350 is largely constructed from composite materials; however, the flight deck area is an exception. Thus, although the crashworthincss assessment ofthe A350 intotal has not been completed, the behavior ofthe flight deck should be consistent with other airplanes ofsimilar size. Although some flight deck floor distortions have been observed after accidents, there has notbeen aproblem with llight deck seat separations due to floor buckling on narrow body and larger airplanes that have aminimum of40 inches of frangible structure between the flight deck floor and the lower fuselage contour. As noted inthe other exemptions referenced by the petitioner, the FAA is considering rulcmaking to change the regulation relative to seats on the flight deck. However, because there are other safety initiatives that are more urgent, there is no schedule forthis action atpresent.

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## rAA's decision

Inconsideration ofthe foregoing, Ifindthat agrant ofexemption is inthe public Il1terest,and will not adversely affect safety. Therefore, pursuant to the authority contained in49 U.S.c. §§ 40IJ3 and 44701, delegated to meby the Administrator, Airbus ishereby granted an exemption from the Ooorwarpage testing requirements of § 25.562(b)(2), Amcndmellt 25-64, to the extent required to permit type certification ofthe Airbus Model A350 forseats mounted in the flight deck. The fol1owing limitations apply to this exemption: 1. This exemption is limited to the Airbus Model A350 series airplanes and applies only to the seats 111the night deck. The scats artofthc flight deck are not exempted. 2. The night deck scats are exempted from compliance with the J0 degrees oftrack misalignment required under §25.562(b)(2). Compliance with al1other requirements of § 25.562 isrequired.

Issued in Renton, Washington, on 

### JAN 22 2010

Ali Bahrami Manager, Transp0l1 Airplane Directorate Aircraft CeJ1ification Service

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