Source: https://www.federalregister.gov/documents/2013/12/19/2013-30234/special-conditions-bombardier-inc-models-bd-500-1a10-and-bd-500-1a11-series-airplanes-seats-with
Timestamp: 2018-04-23 11:59:03
Document Index: 572321591

Matched Legal Cases: ['art 25', 'art 25', 'art 25', '§\u200925', '§\u200925', '§\u200925', 'art 25', '§\u200925', 'art 25', 'art 25']

Federal Register :: Special Conditions: Bombardier Inc., Models BD-500-1A10 and BD-500-1A11 Series Airplanes; Seats With Non-Traditional, Large, Non-Metallic Panels
76734-76736 (3 pages)
Docket No. FAA-2013-1051
Notice No. 25-512-SC
https://www.federalregister.gov/d/2013-30234 https://www.federalregister.gov/d/2013-30234
Send comments identified by docket number FAA-2013-1051 using any of the following methods:
Alan Sinclair, FAA, Airplane and Cabin Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue SW., Renton, Washington, 98057-3356; telephone 425-227-2195; facsimile 425-227-1149.
On December 10, 2009, Bombardier Inc. applied for a type certificate for their new Models BD-500-1A10 and BD-500-1A11 series airplanes (hereafter collectively referred to as “C-series.” The C-series airplanes are swept-wing monoplanes with a pressurized cabin. They share an identical supplier base and significant common design elements. The fuselage is aluminum alloy material, blended double-bubble fuselage, sized for nominal 5-abreast seating. Each airplane's powerplant consists of two under wing Pratt and Whitney PW1524G ultra-high bypass, geared turbofan engines. Flight controls are fly-by-wire flight with two passive/uncoupled side sticks. Avionics includes five landscape primary cockpit displays. The dimension of the airplanes encompass a wingspan of 115 feet; a height of 37.75 feet; and a length of 114.75 feet for the Model BD-500-1A10 and a length of 127 feet for the Model BD-500-1A11. Passenger capacity is designated as 110 for the Model BD-500-1A10 and 125 for the Model BD-500-1A11. Maximum takeoff weight is 131,000 pounds for the Model BD-500-1A10 and 144,000 pounds for the Model BD-500-1A11. Maximum takeoff thrust is 21,000 pounds for the Start Printed Page 76735Model BD-500-1A10 and 23,300 pounds for the Model BD-500-1A11. Range is 3,394 miles (5,463 kilometers) for both models of airplanes. Maximum operating altitude is 41,000 feet for both model airplanes.
The interior arrangements of the C-series airplanes will include passenger and cabin crew seats in the passenger cabin that incorporate non-traditional, large, non-metallic panels in lieu of traditional metal frame and foam/fabric components.
The applicable airworthiness regulations, Title 14, Code of Federal Regulations (14 CFR) part 25, 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 established by the airworthiness standards, these non-traditional, large, non-metallic panels in the cabin must meet the standards of 14 CFR, part 25, appendix F, parts IV and V, heat release and smoke emission requirements.
Under the provisions of 14 CFR 21.17, Bombardier Inc. must show that the C-series airplanes meet the applicable provisions of 14 CFR part 25 as amended by Amendments 25-1 through 25-129 thereto.
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.
A non-traditional large panel, in this case, is defined as a panel with exposed-surface areas greater than 1.5 ft2 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 center consoles, food trays, video monitors and shrouds.
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 the special conditions. These materials must still comply with § 25.853(a) and (c) if used as a covering for a seat cushion or § 25.853(a) if installed elsewhere on the seat. Large non-metallic panels covered with traditional fabrics or leathers will be tested without their coverings.
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, the FAA 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 Compartment interiors, as amended by Amendment 25-61 and Amendment 25-66) extend survival time by approximately two 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, Notice No. 85-10 (50 FR 15038, April 16, 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 Start Printed Page 76736minimum 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 1 ft2 or less may be considered small enough that they do not have to meet the new standards. Components with exposed surface areas greater than 2 ft2 may be considered large enough that they do have to meet the new standards. Those with exposed-surface areas greater than 1 ft2, but less than 2 ft2, must be considered in conjunction with the areas of the cabin in which they are installed before a determination could be made.”
1. Compliance with Title 14 CFR part 25, appendix F, parts IV and V, heat release and smoke emission, is required for seats that incorporate 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 ft2 of non-traditional, non-metallic panel material per seat place that does not have to comply with No. 1. A triple seat assembly may have a total of 4.5 ft2 excluded on any portion of the assembly (e.g., outboard seat place 1 ft2, middle 1 ft2, and inboard 2.5 ft2).
3. Seats need not meet the test requirements of 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 smoke and heat release in their certification basis and do not need to comply with the requirements of 14 CFR 121.312; and
[FR Doc. 2013-30234 Filed 12-18-13; 8:45 am]