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###### Department of Transportation

###### Federal Aviation Administration 

          - 14 CFR Part 25 
          - [Docket No. NM359; Special Conditions No. 25-358-SC] 

# AGENCY:

Federal Aviation Administration (FAA), DOT. 

# ACTION:

Final special conditions. 

# SUMMARY:

These special conditions are issued for Boeing Model 737 series airplanes. These airplanes will have a novel or unusual design feature(s) associated with seats that include non-traditional, large, non-metallic panels that would affect survivability during a post-crash fire event. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards. 

# EFFECTIVE DATE:

The effective date of these special conditions is August 9, 2007. 

# FOR FURTHER INFORMATION CONTACT:

                        Alan Sinclair, FAA, Airframe/Cabin Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 227-2195; facsimile (425) 227-1232; electronic mail                         *alan.sinclair@faa.gov*.                     

# SUPPLEMENTARY INFORMATION:

## Future Requests for Installation of Seats With Non-Traditional, Large, Non-Metallic Panels 

We anticipate that seats with non-traditional, large, non-metallic panels will be installed in other makes and models of airplanes. We have made the determination to require special conditions for all applications requesting the installation of seats with non-traditional, large, non-metallic panels until the airworthiness requirements can be revised to address this issue. Having the same standards across the range of airplane makes and models will ensure a level playing field for the aviation industry. 

## Background 

On August 8, 2005, Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124, applied for a design change to Type Certificate No. A16WE for installation of seats that include non-traditional, large, non-metallic panels in Boeing Model 737-700 series airplanes. The Boeing Model 737 series airplanes, currently approved under Type Certificate No. A16WE, are swept-wing, conventional-tail, twin-engine, turbofan-powered, single aisle, medium sized transport category airplanes. 

The applicable regulations for airplanes currently approved under Type Certificate No. A16WE do not require seats to meet the more stringent flammability standards required of large, non-metallic panels in the cabin interior. At the time the applicable rules were written, seats were designed with a metal frame covered by fabric, not with large, non-metallic panels. Seats also met the then recently adopted standards for flammability of seat cushions. With the seat design being mostly fabric and metal, the contribution to a fire in the cabin had been minimized and was not considered a threat. For these reasons, seats did not need to be tested to heat release and smoke emission requirements. 

Seat designs have now evolved to occasionally include non-traditional, large, non-metallic panels. Taken in total, the surface area of these panels is on the same order as the sidewall and overhead stowage bin interior panels. To provide the level of passenger protection intended by the airworthiness standards, these non-traditional, large, non-metallic panels in the cabin must meet the standards of Title 14 Code of Federal Regulations (CFR), part 25, Appendix F, parts IV and V, heat release and smoke emission requirements. 

## Type Certification Basis 

                    Under the provisions of 14 CFR 21.101, Boeing must show that the Model 737 series airplanes, as changed, continue to meet the applicable provisions of the regulations incorporated by reference in Type Certificate No. A16WE, or the applicable                           ( print page 37426)                        regulations in effect on the date of application for the change. The regulations incorporated by reference in the type certificate are commonly referred to as the “original type certification basis.” The regulations incorporated by reference in Type Certificate No. A16WE are as follows: Title 14 CFR part 25, as amended by Amendment 25-1 through Amendment 25-15, for the Models 737-200, -200C, -300, -400, and -500. Title 14 CFR part 25, as amended by Amendment 25-1 through Amendment 25-77, for the Models 737-600, -700, and -800, with the exceptions listed: Section 25.853(d)(3), Compartment interiors, at Amendment 25-72; and equivalent safety findings, § 25.853(f), Compartment interiors. Title 141 CFR part 25, as amended by Amendment 25-1 through Amendment 25-91, for the Models 737-700C and -900, with the exceptions listed: Section 25.853(d)(3), Compartment interiors, at Amendment 25-72; and equivalent safety findings, § 25.853(f), Compartment interiors. Title 14 CFR part 25, as amended by Amendment 25-1 through Amendment 25-108, for the models 737-900ER, with the exceptions listed: Section 25.853(d)(3), Compartment interiors, at Amendment 25-72; and equivalent safety findings, Section 25.853(f), Compartment interiors.                 

In addition, the certification basis includes certain special conditions, exemptions, or later amended sections of the applicable part that are not relevant to these special conditions. 

If the Administrator finds that the applicable airworthiness regulations (i.e., 14 CFR part 25) do not contain adequate or appropriate safety standards for the Boeing Model 737 series airplanes because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16. 

In addition to the applicable airworthiness regulations and special conditions, the Boeing Model 737 series airplanes must comply with the fuel vent and exhaust emission requirements of 14 CFR part 34 and the noise certification requirements of 14 CFR part 36. 

The FAA issues special conditions as defined in § 11.19, under § 11.38, and they become part of the type certification basis under § 21.101. 

Special conditions are initially applicable to the model for which they are issued. Should the type certificate for that model be amended later to include any other model that incorporates the same or similar novel or unusual design feature, or should any other model already included on the same type certificate be modified to incorporate the same or similar novel or unusual design feature, the special conditions would also apply to the other model under § 21.101. 

## Novel or Unusual Design Features 

The Boeing Model 737 series airplanes will incorporate the following novel or unusual design features: These models offer interior arrangements that include passenger seats that incorporate non-traditional, large, non-metallic panels in lieu of the traditional metal frame covered by fabric. The flammability properties of these panels have been shown to significantly affect the survivability of the cabin in the case of fire. These seats are considered a novel design for transport category airplanes that include Amendment 25-61 and Amendment 25-66 in the certification basis, and were not considered when those airworthiness standards were established. 

The existing regulations do not provide adequate or appropriate safety standards for seat designs that incorporate non-traditional, large, non-metallic panels in their designs. In order to provide a level of safety that is equivalent to that afforded to the balance of the cabin, additional airworthiness standards, in the form of special conditions, are necessary. These special conditions supplement § 25.853. The requirements contained in these special conditions consist of applying the identical test conditions required of all other large panels in the cabin, to seats with non-traditional, large, non-metallic panels. 

## Definition of “Non-Traditional, Large, Non-Metallic Panel” 

A non-traditional, large, non-metallic panel, in this case, is defined as a panel with exposed-surface areas greater than 1.5 square feet installed per seat place. The panel may consist of either a single component or multiple components in a concentrated area. Examples of parts of the seat where these non-traditional panels are installed include, but are not limited to: Seat backs, bottoms and leg/foot rests, kick panels, back shells, credenzas and associated furniture. 

Examples of traditional exempted parts of the seat include: Arm caps, armrest close-outs such as end bays and armrest-styled center consoles, food trays, video monitors and shrouds. 

## Clarification of “Exposed” 

“Exposed” is considered to include those panels directly exposed to the passenger cabin in the traditional sense, plus those panels enveloped such as by a dress cover. Traditional fabrics or leathers currently used on seats are excluded from these special conditions. These materials must still comply with § 25.853(a) and § 25.853(c) if used as a covering for a seat cushion, or § 25.853(a) if installed elsewhere on the seat. Non-traditional, large, non-metallic panels covered with traditional fabrics or leathers will be tested without their coverings or covering attachments. 

## Discussion 

In the early 1980s the FAA conducted extensive research on the effects of post-crash flammability in the passenger cabin. As a result of this research and service experience, we adopted new standards for interior surfaces associated with large surface area parts. Specifically, the rules require measurement of heat release and smoke emission (part 25, Appendix F, parts IV and V) for the affected parts. Heat release has been shown to have a direct correlation with post-crash fire survival time. Materials that comply with the standards (i.e., § 25.853 entitled “Compartment interiors,” as amended by Amendment 25-61 and Amendment 25-66), extend survival time by approximately 2 minutes, over materials that do not comply. 

At the time these standards were written, the potential application of the requirements of heat release and smoke emission to seats was explored. The seat frame itself was not a concern because it was primarily made of aluminum and there were only small amounts of non-metallic materials. It was determined that the overall effect on survivability was negligible, whether or not the food trays met the heat release and smoke requirements. The requirements therefore did not address seats. The preambles to both the Notice of Proposed Rule Making (NPRM), Notice No. 85-10 (50 FR 15038, April16, 1985) and the Final Rule at Amendment 25-61 (51 FR 26206, July 21, 1986), specifically note that seats were excluded “because the recently-adopted standards for flammability of seat cushions will greatly inhibit involvement of the seats.” 

                    Subsequently, the Final Rule at Amendment 25-83 (60 FR 6615, March 6, 1995) clarified the definition of minimum panel size: “It is not possible to cite a specific size that will apply in all installations; however, as a general rule, components with exposed-surface areas of one square foot or less may be considered small enough that they do not have to meet the new standards. Components with exposed-surface areas greater than two square feet may be considered large enough that they do have to meet the new standards. Those                           ( print page 37427)                        with exposed-surface areas greater than one square foot, but less than two square feet, must be considered in conjunction with the areas of the cabin in which they are installed before a determination could be made.”                 

                    In the late 1990s, the FAA issued Policy Memorandum 97-112-39,                     *Guidance for Flammability Testing of Seat/Console Installations*, October 17, 1997 (                    *http://rgl.faa.gov*). That memo was issued when it became clear that seat designs were evolving to include large non-metallic panels with surface areas that would impact survivability during a cabin fire event, comparable to partitions or galleys. The memo noted that large surface area panels must comply with heat release and smoke emission requirements, even if they were attached to a seat. If the FAA had not issued such policy, seat designs could have been viewed as a loophole to the airworthiness standards that would result in an unacceptable decrease in survivability during a cabin fire event.                 

In October of 2004, an issue was raised regarding the appropriate flammability standards for passenger seats that incorporated non-traditional, large, non-metallic panels in lieu of the traditional metal covered by fabric. The Seattle Aircraft Certification Office and Transport Standards Staff reviewed this design and determined that it represented the kind and quantity of material that should be required to pass the heat release and smoke emissions requirements. We have determined that special conditions would be promulgated to apply the standards defined in 14 CFR 25.853(d) to seats with large, non-metallic panels in their design. 

## Discussion of Comments 

                    Notice of proposed special conditions No. 25-06-13-SC, pertaining to Boeing Model 737 series airplanes, was published in the                     **Federal Register**                     on November 9, 2006. Comments were received from Air Tran, Airbus, B/E Aerospace, Boeing, Delta Engineering, the International Coordinating Council of Aerospace Industries Associations (ICCAIA), KLM, and Weber Aircraft LP.                 

## Special Conditions Are Not the Appropriate Means To Establish These Requirements 

Airbus, Boeing, Delta Engineering, ICCAIA, and Weber suggested that the proposed special conditions were not the appropriate way to establish these requirements. These commenters suggested that either the seat technical standard order (TSO) be revised to include the requirements, or that formal rulemaking activity take place to amend Title 14 CFR part 25. 

The commenters stated that including the requirements in either the seat TSO or an amendment to part 25 would ensure that the requirements were applied equally and consistently throughout the FAA and industry. Airbus stated that if the requirements were located in the seat TSO it would reduce the overall administrative burden by requiring a single showing of compliance for a given seat design that may be installed in different types of airplanes. 

*FAA Response:*                     We believe that including these requirements in the context of special conditions is appropriate. The proliferation of the use of large, non-metallic panels in the construction of seats has created a need to issue special conditions to maintain the current level of safety. Special conditions are the best way of introducing these requirements until we determine it is necessary to amend part 25 through the rulemaking process. Also, seats are not required to follow guidance in a TSO to be eligible for installation on an airplane. Furthermore, the proposed TSO C127b includes these standards as optional criteria.                 

## Request To Add Airplane Models to the Applicability 

Air Trans, Boeing, Delta Engineering, ICCAIA, and Weber all suggested that the applicability of the proposed special conditions be expanded and not limited to only Boeing Model 737 series airplanes. The commenters noted that other airplane models certified under 14 CFR part 25 include the same design features identified as “novel or unusual” on Boeing Model 737 series airplanes. 

*FAA Response:*                     We agree that many other airplane models certified under 14 CFR part 25 include “novel or unusual” design features similar to those on Boeing Model 737 series airplanes. We are developing model-specific special conditions for all transport category airplanes operating under part 121 regulations. We will continue to issue special conditions regarding this subject until part 25 is formally amended through the rulemaking process. If part 25 is amended, these requirements will have general applicability instead of model-specific applicability. We are currently using a similar approach for high intensity radiated fields (HIRF) special conditions. The HIRF special conditions will continue to be issued on a model-specific basis until part 25 is amended to include regulations applicable to HIRF.                 

## Request To Add Airplanes Operating Under Part 129 to the Applicability 

Delta Engineering questioned why the proposed special conditions would be applicable to airplanes operated under 14 CFR part 121 and would not be applicable to airplanes operated under 14 CFR part 129. Delta Engineering provided the example of an airplane with a foreign registration. Per the applicability of the proposed special conditions, the requirements of the proposed special conditions would not be applicable because the airplane would be operated in compliance with part 129 operating rules instead of part 121 operating rules. 

*FAA Response:*                     As discussed previously, our intent in adopting these special conditions is to apply them to airplanes that are already required to comply with the smoke and heat release requirements adopted in Amendment 25-61 and Amendment 25-66. Model 737 airplanes with this amendment in their certification basis *                                         are subject to these special conditions, regardless of the operational regulatory parts under which they are operated. Certain other airplanes operated under part 121 are also subject to these requirements as a result of § 121.312, as amended by Amendment 121-189, even if their certification basis does not include Amendment 25-61. However, airplanes with a certification basis preceding Amendment 25-61 and not subject to § 121.312 are not required to comply either with § 25.853 or with these special conditions.                 

## Request To Clarify the Effects of the Proposed Special Conditions on the Existing Fleet 

Air Trans and KLM expressed concern that the requirements in the proposed special conditions would be retroactive and affect the existing airplane fleet or follow-on deliveries of airplanes with previously certified interiors. 

*FAA Response:*                     We have added a new special condition 4 in these special conditions to clarify that only airplanes associated with new seat certification programs will be affected by the requirements in these special conditions. Previously certificated interiors on the existing airplane fleet and follow-on deliveries of airplanes with previously certificated interiors will not be affected.                           ( print page 37428)    

## Request for Justification Regarding Selection of Materials and Quantitative Limits 

Air Tran, B/E Aerospace, and Weber questioned how 1.5 square feet became the maximum area of non-metallic material per seat. B/E stated that the proposed special conditions need further review because the exclusion does not adequately address items traditionally mounted on seat backs. B/E specifically asked if large video monitors would have to comply when installed in seat backs or large, non-metallic panels. 

Weber stated that the proposed special conditions include many exclusions based on the size and location of material. Weber also stated that the quantitative limits for these exclusions do not appear to be based on data. Weber suggested that the proposed special conditions be revised to include justification for the quantitative limits. Furthermore, Weber stated that due to the number of passenger places, First Class seats are limited to a much smaller amount of non-compliant material than Tourist Class seats, despite the fact that there are fewer First Class seats per area of the passenger cabin. Larger seats with fewer passenger places should not have lower quantitative limits on non-compliant material. 

Weber also stated that, based on observation of airplane cabins and the amount of materials in a seat design, the following statement in the proposed special conditions is incorrect: “Seat designs have now evolved to occasionally include non-traditional, large, non-metallic panels. Taken in total, the surface area of these panels is on the same order as the sidewall and overhead stowage bin interior panels.” 

*FAA Response:*                     In 1993, the FAA published a report (DODT/FAA/CT-TN93-13) documenting the results of full-scale testing using panels on seats that did, or did not, comply with heat release and smoke emissions requirements. Those test results showed that limited quantities of material on seats that did not meet heat release and smoke emissions requirements did not raise a safety issue. Amendment 25-83 states that, based on this testing, components with exposed-surface areas greater than one square foot, but less than two square feet, must be considered in conjunction with the areas of the cabin in which they are installed before a determination can be made regarding whether or not they have to meet the heat release and smoke density regulations. Based on that information we determined that 1.5 feet of non-metallic material per seat is appropriate.                 

In response to B/E Aerospace's comment, video monitor installations are not affected by these special conditions. There are existing flammability regulations that cover those installations. 

In response to Weber's comment regarding the size limitations, as noted above, we believe that the quantitative limits are justified. These size limitations are consistent with full-scale test data and the design criteria developed at the time Amendment 25-61 was adopted.  Also, these size limitations were considered during the rulemaking process for Amendment 25-61. 

In response to Weber's comment regarding our statement that the surface areas of some seat installations are equivalent to the amount of material in sidewall and overhead stowage bin interior panels, in our review of applicants' proposed furnishings for passenger cabin installations, we have noticed an increase in the use of large, non-metallic material in proposed seating configurations. Based on those reviews, we believe that our statement is correct. 

## Request To Revise the Type Certification Basis Section 

Boeing noted that the amendment levels for some of the airplanes were incorrectly cited in the Type Certification Basis section of the proposed special conditions. 

*FAA Response:*                     We have revised the Type Certification Basis section to incorporate Boeing's recommended changes.                 

## Request for Clarification of the Testing Method in the “Clarification of Exposed” Paragraph 

B/E Aerospace asked if the non-traditional, large, non-metallic panels covered with traditional fabrics or leathers could be tested without the dress cover. Boeing suggested that the words “or method of covering attachment” be added in the last sentence of the “Clarification of Exposed” paragraph. 

*FAA Response:*                     We agree to revise the last sentence of the “Clarification of Exposed” paragraph to address B/E Aerospace's question and incorporate Boeing's suggestion. In these special conditions that sentence now states “Non-traditional, large, non-metallic panels covered with traditional fabrics or leathers will be tested without their coverings or covering attachments.”                 

## Request for Clarification Regarding Fabric and Thermoplastic Panels 

Airbus requested that the FAA provide information regarding whether or not fabric covered panels are less threatening than thermoplastic ones. No justification was provided for this request. 

*FAA Response:*                     The standards for using fabric, thermoplastic, and leather have been previously established and are applied separately.                 

## Request for a Better Description of Traditional and Non-Traditional Areas/Furnishings 

                    Airbus requested a better description of the console size in the “Definition of ‘Non-Traditional, Large, Non-Metallic Panel ’ ” paragraph of the proposed special conditions. Airbus noted that in the proposed special conditions “Center Consoles” are listed as “traditional exempted areas.” Airbus stated that this may be true for small consoles that “* * * do not protrude the standard seat cushion geometries. However, it is understood that large consoles (which do also divide the forward legroom) are expected to comply with HRR/SD [heat release and smoke density] criteria.” Airbus suggested that this issue should be clarified because FAA Memorandum 97-112-39,                     *Guidance for Flammability Testing of Seat/Console Installations,*                     addresses those larger, separate consoles.                 

B/E Aerospace stated that the definition of non-traditional areas was not adequate and asked about seat backs, seat bottoms, and kick panels. This commenter also asked if fire blocking material is considered a traditional fabric. 

*FAA Response:*                     We agree and have revised this paragraph to include “credenzas” as an additional example of non-traditional areas and “armrest-styled center consoles” as an additional example of traditionally exempted areas. In this final special condition the revised sentences appear as follows: “Examples of nontraditional areas include, but are not limited to: seat backs, bottoms and leg/foot rests, kick panels, back shells, credenzas and associated furniture. Examples of traditional exempted areas include: arm caps, armrest close-outs such as end bays and armrest-styled center consoles, food trays, video monitors and shrouds.”                 

## Request for Additional Testing by the FAA 

                    Airbus, Delta Engineering, ICCAIA, and KLM commented that the FAA should conduct additional testing prior                           ( print page 37429)                        to implementing the proposed special conditions. Airbus and KLM provided similar statements that tests with different amounts of non-traditional, large, non-metallic panels on seats have never been performed to evaluate to what extent the increase in the flammability standard of those seat parts might influence fire safety. ICCAIA stated that the FAA should perform testing to confirm the benefit of issuing the proposed special conditions. ICCAIA noted that seat back shells may be made from parts created from a combination of different materials and sizes. As a result, application of the proposed special conditions would result in multiple tests to determine if the seat back shells were compliant, and the test results would be open to interpretation.                 

Delta Engineering stated that the proposed special condition does not provide information regarding the smoke density and heat release aspects of traditional seat components and that, through testing, the FAA should establish the safety gains related to having the large composite panel compliant with the existing heat release and smoke density requirements. This commenter also stated that the smoke emissions from the seat cushion foam may negate any safety gain related to having the large composite panel compliant with smoke density requirements. In addition, this commenter also questioned whether the FAA conducted extensive testing to confirm that the regulatory standards now being applied to passenger seats are compatible with the requirements in the proposed special conditions. 

*FAA Response:*                     As stated in the proposed special conditions, the FAA has conducted extensive research on the effects of post-crash flammability in the passenger cabin. As a result of that research, combined with service experience, we adopted new airworthiness standards for interior surfaces associated with large surface area parts. The proliferation of the use of large, non-metallic panels in the construction of seats was not anticipated when those airworthiness standards were issued. This increased use of large, non-metallic panels in seating configurations has created a need to issue special conditions to provide the level of passenger protection intended by those airworthiness standards. Seat cushion standards are a separate consideration and were taken into account when these special conditions were created.                 

Furthermore, testing is not required to issue special conditions. The basis for issuing special conditions is that the applicable airworthiness regulations do not contain adequate or appropriate safety standards for a “novel or unusual” design feature. 

## Request for a Cost-Benefit Analysis 

Airbus, B/E Aerospace, ICCAIA, and Weber noted that the proposed special conditions did not include a cost-benefit analysis to support the proposed requirements. Airbus suggested that a cost-benefit analysis should be done through the traditional rulemaking process. ICCAIA stated that the cost-benefit analysis should be conducted because the requirements in the proposed special conditions would be applied to other airplane makes and models. B/E Aerospace and Weber provided similar statements regarding the cost impact to seat manufacturers. Those commenters stated that compliant material is limited and expensive. Weber also stated that significant time and costs would be involved in modifying current designs and developing new materials to comply with the proposed special conditions. 

*FAA Response:*                     When Amendment 25-61 went through the formal rulemaking process a formal economic regulatory analysis was provided. These special conditions effectively serve to maintain the benefits achieved in that amendment by providing an equivalent level of safety for the novel or unusual design feature described earlier. Under Executive Order 12866, these analyses are required only for rules of general applicability. A cost-benefit analysis is not part of the process for proposing special conditions, which apply only to a specified type certificate and are not rules of general applicability.                 

## Request To Clarify the Effective Date of the Proposed Special Conditions 

Air Trans and Boeing both commented on the effective date of the proposed special conditions. Air Trans stated that the proposed special conditions did not include an effective date. Boeing commented that these proposed special conditions should not be applicable upon publication and should not be applicable to the first delivered Model 737-900ER airplane. Boeing noted that it typically takes at least one year for seat manufacturers to incorporate major design changes, such as those required in the proposed special conditions. 

*FAA Response:*                     In response to Air Trans' statement, under standard practice, the effective date of final special conditions is 30 days after the date of publication in the                     **Federal Register**                    . These special conditions follow this practice and will be applicable to all type design changes that include new seat approvals applied for after the effective date of these special conditions.                 

In response to Boeing's comment, as stated previously, the issue regarding large, non-metallic seats is a long standing one and has generated many discussions between the FAA and the aviation industry. Through the Seattle Aircraft Certification Office the FAA has made Boeing aware of the requirements in these special conditions. Since the time the proposed special conditions were published for public comment, the first Boeing Model 737-900ER airplane was delivered; therefore, these special conditions are not applicable to the approved arrangement on that airplane. 

## Request To Extend the Public Comment Period 

Boeing requested that the public comment period for the proposed special conditions be extended from 20 days to 60 days. Boeing stated that the proposed special conditions would require significant design changes to seat components. Airframe and seat manufacturers would need to assess the economic impact of the proposed special conditions and communicate that information to the FAA. 

*FAA Response:*                     The subject of large, non-metallic seat panels is a long standing issue between the FAA and the aviation industry. We have had ongoing discussions with industry representatives in an effort to work out a solution, and the results of these discussions are reflected in these special conditions. We do not agree that an extension to the public comment period is needed or would result in further changes to these special conditions.                 

Except as noted above, these special conditions are adopted as proposed. 

## Applicability 

As discussed above, these special conditions are applicable to Boeing Model 737 series airplanes. Should Boeing apply at a later date for a change to the type certificate to include another model on the same type certificate incorporating the same novel or unusual design feature, the special conditions would apply to that model as well. 

                    Seats do not have to meet these special conditions when installed in compartments that are not otherwise required to meet the test requirements of Title 14 CFR part 25, Appendix F, parts IV and V. For example, airplanes that do not have § 25.853, Amendment 25-61 or later, in their certification basis and those airplanes that do not need to comply with the requirements of 14 CFR 121.312.                           ( print page 37430)    

Only airplanes associated with new certification programs applied for after the effective date of these special conditions will be affected by the requirements in these special conditions. The existing airplane fleet and follow-on deliveries of airplanes with previously certified interiors are not affected. 

## Conclusion 

This action affects only certain novel or unusual design features on Boeing Model 737 series airplanes. It is not a rule of general applicability. 

# List of Subjects in 14 CFR Part 25

      - Aircraft
      - Aviation safety
      - Reporting and recordkeeping requirements

The authority citation for these special conditions is as follows:

Authority:49 U.S.C. 106(g), 40113, 44701, 44702, 44704. 

## The Special Conditions 

Accordingly, pursuant to the authority delegated to me by the Administrator, the following special conditions are issued as part of the type certification basis for Boeing Model 737 series airplanes. 

1. Except as provided in paragraph 3 of these special conditions, compliance with Title 14 CFR part 25, Appendix F, parts IV and V, heat release and smoke emission, is required for seats that corporate non-traditional, large, non-metallic panels that may either be a single component or multiple components in a concentrated area in their design. 

                        2. The applicant may designate up to and including 1.5 square feet of non-traditional, non-metallic panel material per seat place that does not have to comply with special condition Number 1, above. A triple seat assembly may have a total of 4.5 square feet excluded on any portion of the assembly (                        *e.g.*, outboard seat place 1 square foot, middle 1 square foot, and inboard 2.5 square feet).                     

3. Seats do not have to meet the test requirements of Title 14 CFR part 25, Appendix F, parts IV and V, when installed in compartments that are not otherwise required to meet these requirements. Examples include: 

a. Airplanes with passenger capacities of 19 or less, 

b. Airplanes that do not have § 25.853, Amendment 25-61 or later, in their certification basis and are not subject to the requirements of 14 CFR 121.312, and 

c. Airplanes exempted from § 25.853, Amendment 25-61 or later. 

4. Only airplanes associated with new seat certification programs applied for after the effective date of these special conditions will be affected by the requirements in these special conditions. Previously certificated interiors on the existing airplane fleet and follow-on deliveries of airplanes with previously certificated interiors are not affected. 

Issued in Renton, Washington, on June 29, 2007. 

Stephen P. Boyd, 

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. 

# Footnotes

*.                             Model 737-600, -700, -700C, -800, and -900 as of the effective date of these special conditions.                    
        Back to Citation      

[FR Doc. 07-3339  Filed 7-9-07; 8:45 am]

BILLING CODE 4910-13-M