Special Conditions: The Boeing Company, Model 717-200 Series Airplanes; Seats With Inflatable Lapbelts, 36084-36089 [2013-14322]

Download as PDF 36084 * * Federal Register / Vol. 78, No. 116 / Monday, June 17, 2013 / Rules and Regulations * * * Dated: June 11, 2013. Calvin Jenkins, Deputy Associate Administrator for Government Contracting and Business Development. [FR Doc. 2013–14263 Filed 6–14–13; 8:45 am] BILLING CODE 8205–01–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 23 [Docket No. CE308; Special Conditions No. 23–248–SC] Special Conditions: Cirrus Design Corporation Model SF50 Airplane; Function and Reliability Testing; Withdrawal Federal Aviation Administration (FAA), DOT. ACTION: Final special conditions; withdrawal. AGENCY: The FAA is withdrawing a previously published notice granting special conditions for the Cirrus Design Corporation model SF50 airplane. We are withdrawing Special Condition No. 23–248–SC through mutual agreement with Cirrus Design Corporation. DATES: This special condition published on August 18, 2010 at 75 FR 50853 is withdrawn, effective June 17, 2013. FOR FURTHER INFORMATION CONTACT: J. Lowell Foster, Federal Aviation Administration, Small Airplane Directorate, Aircraft Certification Service, 901 Locust, Room 301, Kansas City, MO 64106; telephone (816) 329– 4125; facsimile (816) 329–4090. SUPPLEMENTARY INFORMATION: SUMMARY: mstockstill on DSK4VPTVN1PROD with RULES Background On August 18, 2010, the FAA published Special Condition No. 23– 248–SC for the Cirrus Design Corporation new model SF50 ‘‘Vision’’ Jet. The SF50 is a low-wing, five-plustwo-place (2 children), single-engine turbofan-powered aircraft. It incorporates an Electronic Flight Information System (EFIS), pressurized cabin, retractable gear, and a V-tail. The turbofan engine is mounted on the upper fuselage/tail cone along the aircraft centerline. It is constructed largely of carbon and fiberglass composite materials. Like other Cirrus products, the SF50 includes a ballistically deployed airframe parachute. The model SF50 has a maximum operating altitude of 28,000 feet, where VerDate Mar<15>2010 18:01 Jun 14, 2013 Jkt 229001 it cruises at speeds up to 300 Knots True Air Speed (KTAS). Its MMO will not exceed 0.62 Mach. The maximum takeoff weight will be at or below 6000 pounds with a range at economy cruise of roughly 1000 nm. Cirrus intends for the model SF50 to be certified for single-pilot operations under 14 CFR part 91 and 14 CFR part 135 operating rules. The following operating conditions will be included: • Day and Night VFR • IFR • Flight Into Known Icing Discussion Before Amendment 3–4, Section 3.19 of Civil Air Regulation (CAR) part 3 required service testing of all airplanes type certificated on or after May 15, 1947. The purpose of the testing was to ‘‘ascertain whether there is reasonable assurance that the airplane, its components, and equipment are reliable, and function properly.’’ Amendment 3–4 to CAR part 3 became effective January 15, 1951, and deleted the service test requirements in Section 3.19 for airplanes of 6,000 pounds maximum weight or less. The introductory text published in Amendment 3–4 explained that most of the significant changes in the amendment stemmed from ‘‘the desire for simplification of the rules in this part with respect to the smaller airplanes, specifically those of 6,000 pounds maximum weight or less, which would be expected to be used mainly as personal airplanes.’’ The introductory material also stated the service test requirement was removed for airplanes of 6,000 pounds maximum weight or less because ‘‘experience seems to indicate that this rule imposes a burden upon the manufacturers not commensurate with the safety gained.’’ The requirement for Function and Reliability (F&R) testing, and the exception for airplanes of 6,000 pounds or less maximum weight, is now found in 14 CFR part 21, section 21.35(b)(2). The decision to exempt airplanes of 6,000 pounds maximum weight or less from F&R testing was based on the state of technology envisioned in 1951. At that time, airplanes of 6,000 pounds maximum weight or less were expected to be used mainly as personal airplanes. They used simple, ‘‘stand-alone’’ systems whose failure was more likely to be an inconvenience than an accident. The situation is different today. Technological advances allow airplanes weighing less than 6,000 pounds to be more complex and integrated than some transport airplanes. New part 23 airplanes can incorporate sophisticated equipment not PO 00000 Frm 00002 Fmt 4700 Sfmt 4700 previously used in a part 23 aircraft. Additionally, part 23 airplanes are being used for business and commercial transportation. They should no longer be envisioned mainly as personal airplanes. Therefore, a special condition to require F&R testing for airplanes weighing 6,000 pounds or less is needed where the level of sophistication is beyond evaluating failures by inspection. The model SF50 certification project was granted an extension on September 19, 2011. 14 CFR part 21, Amendment 95, published in the Federal Register (76 FR 64229) on October 18, 2011, incorporated Special Condition No. 23– 248–SC. On December 11, 2012, Cirrus Design Corporation elected to adjust the model SF50 certification basis to Amendment 21–95. Reason for Withdrawal The FAA is withdrawing Special Condition No. 23–248–SC because Cirrus elected to revise the model SF50 certification basis to Amendment 21–95. The authority citation for this Special Condition withdrawal is 49 U.S.C. 106(g), 40113 and 44701; 14 CFR 21.16 and 21.17; and 14 CFR 11.38 and 11.19. Conclusion Withdrawal of this special condition does not preclude the FAA from issuing another notice on the subject matter in the future or committing the agency to any future course of action. Issued in Kansas City, Missouri on June 7, 2013. Earl Lawrence, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 2013–14327 Filed 6–14–13; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 25 [Docket No. FAA–2013–0453; Special Conditions No. 25–489–SC] Special Conditions: The Boeing Company, Model 717–200 Series Airplanes; Seats With Inflatable Lapbelts Federal Aviation Administration (FAA), DOT. ACTION: Final Special Condition; Request for Comments. AGENCY: These special conditions are issued for the Boeing Model 717–200 series airplanes. These airplanes will have a novel or unusual design feature SUMMARY: E:\FR\FM\17JNR1.SGM 17JNR1 mstockstill on DSK4VPTVN1PROD with RULES Federal Register / Vol. 78, No. 116 / Monday, June 17, 2013 / Rules and Regulations associated with seats with inflatable lapbelts. 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. DATES: The effective date of these special conditions is June 12, 2013. We must receive your comments by August 1, 2013. ADDRESSES: Send comments identified by docket number FAA–2013–0453 using any of the following methods: • Federal eRegulations Portal: Go to https://www.regulations.gov/ and follow the online instructions for sending your comments electronically. Mail: Send comments to Docket Operations, M–30, U.S. Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room W12–140, West Building Ground Floor, Washington, DC 20590–0001. Hand Delivery or Courier: Take comments to Docket Operations in Room W12–140 of the West Building Ground Floor at 1200 New Jersey Avenue SE., Washington, DC, between 8 a.m. and 5 p.m., Monday through Friday, except federal holidays. Fax: Fax comments to Docket Operations at 202–493–2251. Privacy: The FAA will post all comments it receives, without change, to https://www.regulations.gov/, including any personal information the commenter provides. Using the search function of the docket Web site, anyone can find and read the electronic form of all comments received into any FAA docket, including the name of the individual sending the comment (or signing the comment for an association, business, labor union, etc.). DOT’s complete Privacy Act Statement can be found in the Federal Register published on April 11, 2000 (65 FR 19477–19478), as well as at https://DocketsInfo.dot. gov/. Docket: Background documents or comments received may be read at https://www.regulations.gov/ at any time. Follow the online instructions for accessing the docket or go to the Docket Operations in Room W12–140 of the West Building Ground Floor at 1200 New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except federal holidays. FOR FURTHER INFORMATION CONTACT: Alan Sinclair, FAA, Airframe and Cabin Safety Branch, ANM–115, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue VerDate Mar<15>2010 18:01 Jun 14, 2013 Jkt 229001 SW., Renton, Washington 98057–3356; telephone 425–227–2195; facsimile 425–227–1232. The FAA has determined that notice of, and opportunity for prior public comment on, these special conditions are unnecessary because the substance of these special conditions has been subject to the public comment process in several prior instances with no substantive comments received. The FAA therefore finds that good cause exists for making these special conditions effective upon issuance. SUPPLEMENTARY INFORMATION: Comments Invited We invite interested people to take part in this rulemaking by sending written comments, data, or views. The most helpful comments reference a specific portion of the special conditions, explain the reason for any recommended change, and include supporting data. We will consider all comments we receive by the closing date for comments. We may change these special conditions based on the comments we receive. Background Model 717–200 Series Airplanes On January 15, 2013, The Boeing Company (referred to as ‘‘Boeing’’ after this point) applied for a change to Type Certificate No. A6WE to install inflatable lapbelts on Boeing Model 717–200 series airplanes. The Model 717–200 series airplanes are narrow body airplanes with twin-jet rearmounted engines. They are equipped with two Rolls-Royce Deutschland Ltd & Co KG BR700–715A1–30 or BR700– 715C1–30 engines. The maximum takeoff weight is 121,000 pounds/ 154,885 kilograms. They have a 134 passenger and 6 crew member capacity. The Model 717–200 series airplanes will use inflatable lapbelts, which are designed to limit the forward excursion of occupants in the event of an accident. This will reduce the potential for head injury, thereby reducing the head injury criteria (HIC) measurement. Inflatable lapbelts behave similarly to automotive inflatable airbags, but in these airplanes, the airbags are integrated into the lapbelts and they inflate away from the seated occupants. While inflatable airbags are now standard in the automotive industry, the use of inflatable lapbelts is novel for commercial aviation. PO 00000 Frm 00003 Fmt 4700 Sfmt 4700 36085 Regulatory Requirements Applicable to Model 717–200 Series Airplanes Title 14, Code of Federal Regulations (14 CFR) 121.311(j) requires that no person may operate a transport category airplane type certificated after January 1, 1958, and manufactured on or after October 27, 2009, in passenger-carrying operations, after October 27, 2009, unless all passenger and flight attendant seats on an airplane operated under part 121 rules meet the requirements of § 25.562 in effect on or after June 16, 1988. The Boeing Model 717–200 series airplanes are required to show compliance with certain aspects of § 25.562 as specified per Type Certificate Data Sheet (TCDS) A6WE. But Boeing Model 717–200 series airplanes manufactured on or after October 27, 2009, operated under part 121 must meet all of the requirements of § 25.562 for passenger and flight attendant seats. Thus, it is in the interest of installers to show full compliance to § 25.562, so that an operator under part 121 may be able to use the airplanes without having to do additional certification work. Also, some foreign civil airworthiness authorities have invoked these same operator requirements in the form of airworthiness directives. Section 25.785 requires that occupants be protected from head injury by either ensuring that any object that could injure them is outside the striking radius of their heads or adding padding. Traditionally, this has required seats to be set back so that occupants’ heads are 35 inches from any bulkhead or other rigid interior feature. If this is not practical, specified types of padding must be added. The relative effectiveness of these means of injury protection was not quantified. Amendment 25–64 to 14 CFR part 25, specifically § 25.562, created a new standard that quantifies required head injury protection. Section 25.562 requires that for seat and restraint systems, applicants must use dynamic tests or analysis to demonstrate that persons do not suffer serious head injury under specific conditions. Section 25.562 also requires that protection must be provided or the seat must be designed so that the head impact does not exceed a HIC of 1,000 units. While the test conditions described for HIC are detailed and specific, it is the intent of the requirement that an adequate level of head injury protection be provided for passengers in a severe crash. Because §§ 25.562 and 25.785 and associated guidance do not adequately E:\FR\FM\17JNR1.SGM 17JNR1 36086 Federal Register / Vol. 78, No. 116 / Monday, June 17, 2013 / Rules and Regulations address seats with inflatable lapbelts, the FAA recognizes that appropriate pass/fail criteria need to be developed that do fully address the safety concerns specific to occupants of these seats. mstockstill on DSK4VPTVN1PROD with RULES Advantages of Inflatable Lapbelts Inflatable lapbelts have two potential advantages over other means of headimpact protection. First, they can provide significantly greater protection than energy-absorbing pads, and, second, they can provide essentially equivalent protection for all occupants, regardless of stature. These are significant advantages from a safety standpoint, because inflatable lapbelts will likely provide a level of safety that exceeds the minimum standards of the Code of Federal Regulations. Conversely, inflatable lapbelts in general are active systems and must be relied upon to activate properly when needed, as opposed to energy-absorbing pads or upper torso restraints that are passive and always available. Therefore, the potential advantages must be balanced against this and other potential disadvantages to develop standards for this design feature. Unique Concerns for Inflatable Lapbelts in Airplanes While the automotive industry has extensive experience demonstrating the benefits of using inflatable airbags, the airplane environment presents unique and additional challenges. From the standpoint of a passenger safety system, inflatable lapbelts are unique in that they are both active and entirely autonomous devices. In automobiles, airbags are a supplemental system and work in conjunction with upper torso restraints. In airplanes, inflatable lapbelts are the sole means of injury protection for occupants, i.e., they are not used in conjunction with additional restraints. In addition, automobile crash events have more definable beginnings and ends, and they do not typically last as long as aviation crash events, which can simplify the activation logic. The airplane-operating environment is also quite different from that of automobiles in terms of both the interior design and the exterior environment in which the airplane operates. Airplane cabin furnishings potentially receive greater wear and tear and unanticipated abuse conditions (for example, because of galley loading and damage from passenger baggage). Airplanes also operate at altitudes where exposure to high-intensity radiomagnetic fields (HIRF) could affect the lapbelts’ activation system. The FAA considers inflatable lapbelts to have two primary safety concerns: VerDate Mar<15>2010 18:01 Jun 14, 2013 Jkt 229001 first, that they perform properly under foreseeable operating conditions, and second, that they do not perform (i.e., activate) in a manner or at times that would result in a hazard to the airplane or occupants. This latter point has the potential to be the more rigorous of the requirements, owing to the active nature of the system. The discussion below addresses how these special conditions address the specific issues raised by these two general concerns. Type Certification Basis Under the provisions of § 21.101 Boeing must show that the Model 717– 200 series airplanes, as changed, continue to meet the applicable provisions of the regulations incorporated by reference in Type Certificate No. A6WE or the applicable 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. A6WE are as follows: part 25 of the Federal Aviation Regulations as amended by Amendments 25–1 through 25–82, except where superseded. The U.S. type certification basis for the Model 717– 200 series airplanes is established in accordance with 14 CFR 21.29 and 21.17 and the type certification application date. The U.S. type certification basis is listed in Type Certificate No. A6WE. 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 717–200 series airplanes because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16. 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 novel or unusual design feature, or should any other model already included on the same type certificate be modified to incorporate the same novel or unusual design feature, the special conditions would also apply to the other model. In addition to the applicable airworthiness regulations and special conditions, the Model 717–200 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. PO 00000 Frm 00004 Fmt 4700 Sfmt 4700 The FAA issues special conditions, as defined in 14 CFR 11.19, in accordance with § 11.38, and they become part of the type-certification basis under § 21.101. Novel or Unusual Design Features The Boeing Model 717–200 series airplanes will incorporate the following novel or unusual design features: inflatable lapbelts on certain seats of the Model 717–200 series airplanes to reduce the potential for head injury in the event of an accident. Inflatable lapbelts work similarly to automotive airbags, except the airbags are integrated with the lapbelts of the restraint system. The CFR states the performance criteria for head injury protection in objective terms. However, none of these criteria are adequate to address the specific issues raised concerning seats with inflatable lapbelts. The FAA has therefore determined that, in addition to the requirements of part 25, special conditions are needed to address requirements particular to installation of seats with inflatable lapbelts. Accordingly, in addition to the passenger injury criteria specified in § 25.785, these special conditions are proposed for the Boeing Model 717–200 series airplanes equipped with inflatable lapbelts. Other conditions may be developed, as needed, based on further FAA review and discussions with the manufacturer and civil aviation authorities. Discussion The FAA considers inflatable lapbelts to have two primary safety concerns: first, that they perform properly under foreseeable operating conditions, and second, that they do not perform (i.e., activate) in a manner or at times that would result in a hazard to the airplane or occupants. Effective for Wide Range of Occupants Inflatable lapbelts should be effective for a wide range of occupants. The FAA has historically considered the range from the fifth percentile female to the ninety-fifth percentile male as the range of occupants that must be taken into account. In this case, the FAA is proposing consideration of a broader range of occupants, due to the nature of the lapbelt installation and its close proximity to the occupant. In a similar vein, these persons could have assumed the brace position for accidents in which an impact is anticipated. Test data indicate that occupants in the brace position do not require supplemental protection, and so it would not be necessary to show that inflatable lapbelts will enhance the brace position. E:\FR\FM\17JNR1.SGM 17JNR1 Federal Register / Vol. 78, No. 116 / Monday, June 17, 2013 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES However, the inflatable lapbelts must not introduce any hazards when they deploy into seated, braced occupants. Another area of concern is children in these seats whether lap-held, in approved child safety seats, or occupying the seat directly. Although specifically prohibited by the FAA operating regulations, the use of the supplementary loop belt (‘‘belly belt’’) may be required by other civil aviation authorities, and should also be considered with the end goal of meeting those regulations. Similarly, if the seat is occupied by a pregnant woman, the installation needs to address such usage, either by demonstrating that it will function properly, or by adding appropriate limitation on usage. No Resulting Hazards From Proper Functioning To be an effective safety system, inflatable lapbelts must function properly and must not introduce any additional hazards to occupants as a result of their functioning. There are several areas where inflatable lapbelts differ from traditional occupant protection systems and require special conditions to ensure adequate performance. Inflatable lapbelts are essentially single-use devices. As a result, they could potentially deploy under crash conditions that are not sufficiently severe as to require head injury protection from the inflatable lapbelts. Since crashes are frequently composed of a series of impacts before the airplane comes to rest, if a larger impact follows the initial impact, the inflatable lapbelts could be rendered useless. Other safety devices such as energy absorbing pads or upper torso restraints tend to provide continuous protection regardless of severity or number of impacts in a crash event. Therefore, the inflatable lapbelts should provide protection when required and they should not expend their protection during a less severe impact. Also, it is possible to have several large impact events during the course of a crash, but there will be no requirement for the inflatable lapbelts to provide protection for multiple impacts. Each occupant’s restraint system is designed to provide protection for only that occupant. However, unoccupied seats that may have active lapbelts are also a concern. It will be necessary to show that the required protection is provided for each occupant, regardless of the number of occupied seats. Impact on Egress Since the inflatable lapbelts likely have a large volume displacement, the inflated bags could potentially impede VerDate Mar<15>2010 18:01 Jun 14, 2013 Jkt 229001 egress of passengers. Since the bags deflate to absorb energy, it is likely that the inflatable lapbelts would be deflated at the time that persons would be trying to leave their seats. Nonetheless, it is appropriate to specify a time interval after which the inflatable lapbelts may not impede rapid egress. Ten seconds has been chosen as a reasonable time, since this corresponds to the maximum time allowed for an exit to be opened (in accordance with § 25.809). In actuality, it is unlikely that a flight attendant would be able to prepare an exit this quickly, especially in an accident that is severe enough to deploy the inflatable lapbelts. Furthermore, the inflatable lapbelts will likely deflate much more quickly than ten seconds. It is even more critical that the inflatable lapbelts do not impede rapid egress in the emergency exit row seats. Section 25.813 clearly requires that there must be an unobstructed passageway from the main aisle to the exit and that there must be no interference in opening the exit. The restraint system must not impede access to and the opening of the exit. In some cases, such as a Type III over-wing hatch, a passenger is the one who will open the exit. These lapbelts should be evaluated in the exit row under existing regulations (§§ 25.809 and 25.813) and guidance material. The inflatable lapbelts must also be evaluated in postcrash conditions. They should be evaluated using representative restraint systems in the bag deployed condition. This evaluation includes reviewing the access to and opening of the exit, specifically looking for obstructions in the egress path and any interference in opening the exit. Each unique interior configuration must be considered (e.g., passageway width and single, or dual passageways with the outboard seat removed). If restraints create any obstruction or interference, they could impede rapid egress. If these restraint systems are installed at exit door rows, it is likely that project-specific guidance will be necessary. Availability When Needed These special conditions include requirements to ensure that inflatable lapbelts operate in the aviation environment. These special conditions also incorporate requirements to ensure that the inflatable lapbelts are protected from HIRF and meet the requirements of § 25.1316. Existing regulations regarding lightning, § 25.1316, and the existing HIRF special condition for the Boeing Model 717–200 series aircraft, Special Conditions No. 25–ANM–60 (57 FR 34511, August 5, 1992), are also applicable. PO 00000 Frm 00005 Fmt 4700 Sfmt 4700 36087 Since inflatable lapbelts will be electrically powered, the system could possibly fail if the fuselage separates. Since this system is intended as crash/ post-crash protection means, failure due to fuselage separation is not acceptable. As with emergency lighting, the system should function properly if such a separation occurs at any point in the fuselage. Inflatable lapbelts will rely on electronic sensors for signaling and pyrotechnic charges for activation so that they are available when needed. Prevention of Inadvertent Activation Inflatable lapbelts could be susceptible to inadvertent activation, causing them to deploy in a potentially unsafe manner. The consequences of such deployment must be considered in establishing the reliability of the system. Therefore, Boeing must substantiate that if the lapbelts inadvertently deploy, they will not create a hazard to the airplane. If this cannot be substantiated, then Boeing must demonstrate that inadvertent deployment is an extremely improbable occurrence (i.e., less than 10¥9 per flight hour). Also, if the lapbelts are inadvertently deployed, the effects on passengers or crew members who are standing or sitting close by should also be considered. A minimum reliability level will have to be established for this case, depending upon the consequences, even if the effect on the airplane is negligible. In-service and outside environmental conditions could increase the potential for inadvertent activation. The cumulative effects of wear and tear must also be considered so that it does not increase the likelihood of an inadvertent deployment to an unacceptable level. To mitigate the effects of such cumulative damage, it is necessary to develop an appropriate inspection interval and selftest capability. Environmental conditions, such as lightning and HIRF, could potentially affect inflatable lapbelt systems. To demonstrate compliance in such conditions, it is first necessary to determine whether the lapbelts are critical or essential systems. If inadvertent deployment could cause a hazard to the airplane, inflatable lapbelts are considered a critical system; if inadvertent deployment could cause injuries to persons, the inflatable lapbelts are considered an essential system. Finally, the inflatable lapbelt installation should be protected from the effects of fire, so, for example, a rupture of the pyrotechnic squib does not create an additional hazard. Flammability Special Conditions No. 25–187–SC (66 FR 52017, October 12, 2001) issued E:\FR\FM\17JNR1.SGM 17JNR1 mstockstill on DSK4VPTVN1PROD with RULES 36088 Federal Register / Vol. 78, No. 116 / Monday, June 17, 2013 / Rules and Regulations for the Boeing Model 777 series airplanes was the first special conditions to address flammability of the airbag material. The Boeing Model 717–200 series airplanes will use the similar airbag material in their inflatable lapbelts. During the development of inflatable lapbelts, the manufacturer was unable to develop a fabric that would meet the inflation requirements for the bag and the flammability requirements of part I(a)(1)(ii) of appendix F to part 25. The fabrics that were developed that meet the flammability requirement did not produce acceptable deployment characteristics. However, the manufacturer was able to develop a fabric that meets the less stringent flammability requirements of part I(a)(1)(iv) of appendix F to part 25 and has acceptable deployment characteristics. Part I of appendix F to part 25 specifies the flammability requirements for interior materials and components. Appendix F does not explicitly reference inflatable restraint systems, because they did not exist when the flammability requirements were written. The existing requirements are based on both material types, as well as use, and have been specified in light of the stateof-the-art materials available to perform a given function. In the absence of a specific reference, the default requirement would be for the type of material used to construct the inflatable restraint, which is a fabric in this case. However, in issuing special conditions, the FAA must also consider the use of the material and whether the default requirement is appropriate. In this case, the specialized function of the inflatable restraints means that highly specialized materials are needed. The standard normally applied to fabrics is a 12-second vertical ignition test. However, materials that meet this standard do not perform adequately as inflatable restraints. Since the safety benefits of the inflatable restraints are very significant, the flammability standard appropriate for these devices should not screen out suitable materials, thereby effectively eliminating use of inflatable restraints. The FAA will need to establish a balance between the safety benefit of the inflatable restraints and flammability performance. At this time, the 2.5-inch per minute horizontal test is considered to provide that balance. As materials standards and technology change (which is expected), the FAA may change this standard in subsequent special conditions to account for improved materials. As discussed previously, the following special conditions can be VerDate Mar<15>2010 18:01 Jun 14, 2013 Jkt 229001 characterized as addressing either the safety performance of the system or the system’s integrity against inadvertent activation. Because a crash requiring use of the inflatable lapbelts is a relatively rare event, and because the consequences of an inadvertent activation are potentially quite severe, these latter requirements are probably the more rigorous from a design standpoint. Finally, it should be noted that the special conditions are applicable to the inflatable lapbelt system as installed. The special conditions are not an installation approval. Therefore, while the special conditions relate to each such system installed, the overall type certificate or supplemental type certificate approval is a separate finding and must consider the combined effects of all such systems installed. For the reasons discussed above, 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. Applicability As discussed above, these special conditions are applicable to the Model 717–200 series airplanes. Should Boeing apply at a later date for a change to the type certificate to include another model incorporating the same novel or unusual design feature, the special conditions would apply to that model as well. Conclusion This action affects only certain novel or unusual design features on one model series of airplanes. It is not a rule of general applicability. The substance of these special conditions has been subjected to the notice and comment period in several prior instances and has been derived without substantive change from those previously issued. It is unlikely that prior public comment would result in a significant change from the substance contained herein. Therefore, the FAA has determined that prior public notice and comment are unnecessary and good cause exists for adopting these special conditions upon issuance. The FAA is requesting comments to allow interested persons to submit views that may not have been submitted in response to the prior opportunities for comment described above. 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: PO 00000 Frm 00006 Fmt 4700 Sfmt 4700 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 717–200 series airplanes equipped with inflatable lapbelts. 1. Seats with Inflatable Lapbelts. It must be shown that the inflatable lapbelt will deploy and provide protection under crash conditions where it is necessary to prevent serious head injury. The means of protection must take into consideration a range of stature from a two-year-old child to a ninety-fifth percentile male. The inflatable lapbelt must provide a consistent approach to energy absorption throughout that range of occupants. In addition, the following situations must be considered: a. The seat occupant is holding an infant. b. The seat occupant is a child in a child restraint device. c. The seat occupant is a child not using a child restraint device. d. The seat occupant is a pregnant woman. 2. The inflatable lapbelt must provide adequate protection for each occupant regardless of the number of occupants of the seat assembly, considering that unoccupied seats may have active seatbelts. 3. The design must prevent the inflatable lapbelt from being either incorrectly buckled or incorrectly installed such that the inflatable lapbelt would not properly deploy. Alternatively, it must be shown that such deployment is not hazardous to the occupant, and will provide the required head injury protection. 4. It must be shown that the inflatable lapbelt system is not susceptible to inadvertent deployment as a result of wear and tear, or inertial loads resulting from in-flight or ground maneuvers (including gusts and hard landings), and other operating and environmental conditions (vibrations, moisture, etc.) likely to be experienced in service. 5. Deployment of the inflatable lapbelt must not introduce injury mechanisms to the seated occupant, or result in injuries that could impede rapid egress. This assessment should include an occupant who is in the brace position when it deploys and an occupant whose belt is loosely fastened. 6. It must be shown that inadvertent deployment of the inflatable lapbelt, during the most critical part of the flight, will either not cause a hazard to E:\FR\FM\17JNR1.SGM 17JNR1 Federal Register / Vol. 78, No. 116 / Monday, June 17, 2013 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES the airplane or its occupants, or it meets the requirement of § 25.1309(b). 7. It must be shown that the inflatable lapbelt will not impede rapid egress of occupants 10 seconds after its deployment. 8. The system must be protected from lightning and high intensity radiomagnetic fields (HIRF). The threats specified in existing regulations regarding lightning, § 25.1316, and existing HIRF special conditions for the Boeing Model 717–200 series airplanes, Special Conditions No. 25–ANM–60, are incorporated by reference for the purpose of measuring lightning and HIRF protection. 9. Inflatable lapbelts, once deployed, must not adversely affect the emergency lighting system (e.g., block proximity lights to the extent that the lights no longer meet their intended function). 10. The inflatable lapbelt must function properly after loss of normal aircraft electrical power, and after a transverse separation of the fuselage at the most critical location. A separation at the location of the lapbelt does not have to be considered. 11. It must be shown that the inflatable lapbelt will not release hazardous quantities of gas or particulate matter into the cabin. 12. The inflatable lapbelt installation must be protected from the effects of fire such that no hazard to occupants will result. 13. There must be a means for a crew member to verify the integrity of the inflatable lapbelt activation system prior to each flight, or it must be demonstrated to reliably operate between inspection intervals. The FAA considers the loss of the airbag system deployment function alone (i.e., independent of the conditional event that requires the airbag system deployment) to be a major failure condition. 14. The inflatable material may not have an average burn rate of greater than 2.5 inches/minute when tested using the horizontal flammability test as defined in 14 CFR part 25, appendix F, part I, paragraph (b)(5). Issued in Renton, Washington, on June 12, 2013. Jeffrey E. Duven, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2013–14322 Filed 6–14–13; 8:45 am] BILLING CODE 4910–13–P VerDate Mar<15>2010 18:01 Jun 14, 2013 Jkt 229001 DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2013–0462; Directorate Identifier 2013–NM–092–AD; Amendment 39–17476; AD 2013–11–16] RIN 2120–AA64 Airworthiness Directives; Hawker Beechcraft Corporation (Type Certificate Previously Held by Raytheon Aircraft Company) Airplanes We are adopting a new airworthiness directive (AD) for certain Hawker Beechcraft Corporation (Type Certificate Previously Held by Raytheon Aircraft Company) Model BAe.125 Series 800A (including C–29A and U– 125), and 800B airplanes; and Model Hawker 800 (including variant U–125A) and 800XP airplanes modified in accordance with a certain winglet supplemental type certificate. This AD requires revising the Limitations section of the airplane flight manual (AFM) and installing placards on the instrument panel. This AD was prompted by reports of several instances of severe vibration and wing/aileron oscillations. We are issuing this AD to prevent vibration and wing/aileron oscillations, which could cause structural damage or lead to divergent flutter, and result in loss of integrity of the wing, loss of control of the airplane, and in-flight breakup. DATES: This AD is effective July 2, 2013. The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of July 2, 2013. We must receive comments on this AD by August 1, 2013. ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments. • Fax: 202–493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590. • Hand Delivery: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590, between 9 a.m. PO 00000 Frm 00007 Fmt 4700 Sfmt 4700 and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this AD, contact Aviation Partners Inc., 7299 Perimeter Road South, Seattle, WA 98108; telephone 800–946–4538; email info@aviationpartners.com; Internet https://www.aviationpartners.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221. Examining the AD Docket Federal Aviation Administration (FAA), DOT. ACTION: Final rule; request for comments. AGENCY: SUMMARY: 36089 You may examine the AD docket on the Internet at https:// www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: 800–647– 5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Kathleen Arrigotti, Aerospace Engineer, Airframe Branch, ANM–120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057–3356; phone: (425) 917–6426; fax: (425) 917–6590; email: kathleen.arrigotti@faa.gov. SUPPLEMENTARY INFORMATION: Discussion We have received reports of several instances of severe vibration and wing/ aileron oscillation due to lack of sufficient flutter margin with winglets installed. This condition, if not corrected, could cause structural damage or lead to divergent flutter, and result in loss of integrity of the wing, loss of control of the airplane, and inflight breakup. Relevant Service Information We reviewed Aviation Partners Service Bulletin SBH–13–001, Revision A, dated May 3, 2013. The service information describes procedures for revising the Limitations section of the AFM to include an altitude restriction, and installing placards on the instrument panel. FAA’s Determination We are issuing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design. E:\FR\FM\17JNR1.SGM 17JNR1

Agencies

[Federal Register Volume 78, Number 116 (Monday, June 17, 2013)]
[Rules and Regulations]
[Pages 36084-36089]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-14322]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2013-0453; Special Conditions No. 25-489-SC]


Special Conditions: The Boeing Company, Model 717-200 Series 
Airplanes; Seats With Inflatable Lapbelts

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final Special Condition; Request for Comments.

-----------------------------------------------------------------------

SUMMARY: These special conditions are issued for the Boeing Model 717-
200 series airplanes. These airplanes will have a novel or unusual 
design feature

[[Page 36085]]

associated with seats with inflatable lapbelts. 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.

DATES: The effective date of these special conditions is June 12, 2013. 
We must receive your comments by August 1, 2013.

ADDRESSES: Send comments identified by docket number FAA-2013-0453 
using any of the following methods:
     Federal eRegulations Portal: Go to https://www.regulations.gov/ and follow the online instructions for sending 
your comments electronically.
    Mail: Send comments to Docket Operations, M-30, U.S. Department of 
Transportation (DOT), 1200 New Jersey Avenue SE., Room W12-140, West 
Building Ground Floor, Washington, DC 20590-0001.
    Hand Delivery or Courier: Take comments to Docket Operations in 
Room W12-140 of the West Building Ground Floor at 1200 New Jersey 
Avenue SE., Washington, DC, between 8 a.m. and 5 p.m., Monday through 
Friday, except federal holidays.
    Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to https://www.regulations.gov/, including any personal 
information the commenter provides. Using the search function of the 
docket Web site, anyone can find and read the electronic form of all 
comments received into any FAA docket, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478), as well as at https://DocketsInfo.dot.gov/ gov/.
    Docket: Background documents or comments received may be read at 
https://www.regulations.gov/ at any time. Follow the online instructions 
for accessing the docket or go to the Docket Operations in Room W12-140 
of the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except federal holidays.

FOR FURTHER INFORMATION CONTACT: Alan Sinclair, FAA, Airframe 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 425-227-1232.

SUPPLEMENTARY INFORMATION: The FAA has determined that notice of, and 
opportunity for prior public comment on, these special conditions are 
unnecessary because the substance of these special conditions has been 
subject to the public comment process in several prior instances with 
no substantive comments received. The FAA therefore finds that good 
cause exists for making these special conditions effective upon 
issuance.

Comments Invited

    We invite interested people to take part in this rulemaking by 
sending written comments, data, or views. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data.
    We will consider all comments we receive by the closing date for 
comments. We may change these special conditions based on the comments 
we receive.

Background

Model 717-200 Series Airplanes

    On January 15, 2013, The Boeing Company (referred to as ``Boeing'' 
after this point) applied for a change to Type Certificate No. A6WE to 
install inflatable lapbelts on Boeing Model 717-200 series airplanes. 
The Model 717-200 series airplanes are narrow body airplanes with twin-
jet rear-mounted engines. They are equipped with two Rolls-Royce 
Deutschland Ltd & Co KG BR700-715A1-30 or BR700-715C1-30 engines. The 
maximum takeoff weight is 121,000 pounds/154,885 kilograms. They have a 
134 passenger and 6 crew member capacity.
    The Model 717-200 series airplanes will use inflatable lapbelts, 
which are designed to limit the forward excursion of occupants in the 
event of an accident. This will reduce the potential for head injury, 
thereby reducing the head injury criteria (HIC) measurement. Inflatable 
lapbelts behave similarly to automotive inflatable airbags, but in 
these airplanes, the airbags are integrated into the lapbelts and they 
inflate away from the seated occupants. While inflatable airbags are 
now standard in the automotive industry, the use of inflatable lapbelts 
is novel for commercial aviation.

Regulatory Requirements Applicable to Model 717-200 Series Airplanes

    Title 14, Code of Federal Regulations (14 CFR) 121.311(j) requires 
that no person may operate a transport category airplane type 
certificated after January 1, 1958, and manufactured on or after 
October 27, 2009, in passenger-carrying operations, after October 27, 
2009, unless all passenger and flight attendant seats on an airplane 
operated under part 121 rules meet the requirements of Sec.  25.562 in 
effect on or after June 16, 1988.
    The Boeing Model 717-200 series airplanes are required to show 
compliance with certain aspects of Sec.  25.562 as specified per Type 
Certificate Data Sheet (TCDS) A6WE. But Boeing Model 717-200 series 
airplanes manufactured on or after October 27, 2009, operated under 
part 121 must meet all of the requirements of Sec.  25.562 for 
passenger and flight attendant seats. Thus, it is in the interest of 
installers to show full compliance to Sec.  25.562, so that an operator 
under part 121 may be able to use the airplanes without having to do 
additional certification work. Also, some foreign civil airworthiness 
authorities have invoked these same operator requirements in the form 
of airworthiness directives.
    Section 25.785 requires that occupants be protected from head 
injury by either ensuring that any object that could injure them is 
outside the striking radius of their heads or adding padding. 
Traditionally, this has required seats to be set back so that 
occupants' heads are 35 inches from any bulkhead or other rigid 
interior feature. If this is not practical, specified types of padding 
must be added. The relative effectiveness of these means of injury 
protection was not quantified. Amendment 25-64 to 14 CFR part 25, 
specifically Sec.  25.562, created a new standard that quantifies 
required head injury protection.
    Section 25.562 requires that for seat and restraint systems, 
applicants must use dynamic tests or analysis to demonstrate that 
persons do not suffer serious head injury under specific conditions. 
Section 25.562 also requires that protection must be provided or the 
seat must be designed so that the head impact does not exceed a HIC of 
1,000 units. While the test conditions described for HIC are detailed 
and specific, it is the intent of the requirement that an adequate 
level of head injury protection be provided for passengers in a severe 
crash.
    Because Sec. Sec.  25.562 and 25.785 and associated guidance do not 
adequately

[[Page 36086]]

address seats with inflatable lapbelts, the FAA recognizes that 
appropriate pass/fail criteria need to be developed that do fully 
address the safety concerns specific to occupants of these seats.

Advantages of Inflatable Lapbelts

    Inflatable lapbelts have two potential advantages over other means 
of head-impact protection. First, they can provide significantly 
greater protection than energy-absorbing pads, and, second, they can 
provide essentially equivalent protection for all occupants, regardless 
of stature. These are significant advantages from a safety standpoint, 
because inflatable lapbelts will likely provide a level of safety that 
exceeds the minimum standards of the Code of Federal Regulations. 
Conversely, inflatable lapbelts in general are active systems and must 
be relied upon to activate properly when needed, as opposed to energy-
absorbing pads or upper torso restraints that are passive and always 
available. Therefore, the potential advantages must be balanced against 
this and other potential disadvantages to develop standards for this 
design feature.

Unique Concerns for Inflatable Lapbelts in Airplanes

    While the automotive industry has extensive experience 
demonstrating the benefits of using inflatable airbags, the airplane 
environment presents unique and additional challenges. From the 
standpoint of a passenger safety system, inflatable lapbelts are unique 
in that they are both active and entirely autonomous devices. In 
automobiles, airbags are a supplemental system and work in conjunction 
with upper torso restraints. In airplanes, inflatable lapbelts are the 
sole means of injury protection for occupants, i.e., they are not used 
in conjunction with additional restraints. In addition, automobile 
crash events have more definable beginnings and ends, and they do not 
typically last as long as aviation crash events, which can simplify the 
activation logic.
    The airplane-operating environment is also quite different from 
that of automobiles in terms of both the interior design and the 
exterior environment in which the airplane operates. Airplane cabin 
furnishings potentially receive greater wear and tear and unanticipated 
abuse conditions (for example, because of galley loading and damage 
from passenger baggage). Airplanes also operate at altitudes where 
exposure to high-intensity radiomagnetic fields (HIRF) could affect the 
lapbelts' activation system.
    The FAA considers inflatable lapbelts to have two primary safety 
concerns: first, that they perform properly under foreseeable operating 
conditions, and second, that they do not perform (i.e., activate) in a 
manner or at times that would result in a hazard to the airplane or 
occupants. This latter point has the potential to be the more rigorous 
of the requirements, owing to the active nature of the system. The 
discussion below addresses how these special conditions address the 
specific issues raised by these two general concerns.

Type Certification Basis

    Under the provisions of Sec.  21.101 Boeing must show that the 
Model 717-200 series airplanes, as changed, continue to meet the 
applicable provisions of the regulations incorporated by reference in 
Type Certificate No. A6WE or the applicable 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. A6WE are as follows: part 25 of the 
Federal Aviation Regulations as amended by Amendments 25-1 through 25-
82, except where superseded. The U.S. type certification basis for the 
Model 717-200 series airplanes is established in accordance with 14 CFR 
21.29 and 21.17 and the type certification application date. The U.S. 
type certification basis is listed in Type Certificate No. A6WE.
    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 717-200 series 
airplanes because of a novel or unusual design feature, special 
conditions are prescribed under the provisions of Sec.  21.16.
    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 novel or 
unusual design feature, or should any other model already included on 
the same type certificate be modified to incorporate the same novel or 
unusual design feature, the special conditions would also apply to the 
other model.
    In addition to the applicable airworthiness regulations and special 
conditions, the Model 717-200 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 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type-
certification basis under Sec.  21.101.

Novel or Unusual Design Features

    The Boeing Model 717-200 series airplanes will incorporate the 
following novel or unusual design features: inflatable lapbelts on 
certain seats of the Model 717-200 series airplanes to reduce the 
potential for head injury in the event of an accident. Inflatable 
lapbelts work similarly to automotive airbags, except the airbags are 
integrated with the lapbelts of the restraint system.
    The CFR states the performance criteria for head injury protection 
in objective terms. However, none of these criteria are adequate to 
address the specific issues raised concerning seats with inflatable 
lapbelts. The FAA has therefore determined that, in addition to the 
requirements of part 25, special conditions are needed to address 
requirements particular to installation of seats with inflatable 
lapbelts.
    Accordingly, in addition to the passenger injury criteria specified 
in Sec.  25.785, these special conditions are proposed for the Boeing 
Model 717-200 series airplanes equipped with inflatable lapbelts. Other 
conditions may be developed, as needed, based on further FAA review and 
discussions with the manufacturer and civil aviation authorities.

Discussion

    The FAA considers inflatable lapbelts to have two primary safety 
concerns: first, that they perform properly under foreseeable operating 
conditions, and second, that they do not perform (i.e., activate) in a 
manner or at times that would result in a hazard to the airplane or 
occupants.

Effective for Wide Range of Occupants

    Inflatable lapbelts should be effective for a wide range of 
occupants. The FAA has historically considered the range from the fifth 
percentile female to the ninety-fifth percentile male as the range of 
occupants that must be taken into account. In this case, the FAA is 
proposing consideration of a broader range of occupants, due to the 
nature of the lapbelt installation and its close proximity to the 
occupant. In a similar vein, these persons could have assumed the brace 
position for accidents in which an impact is anticipated. Test data 
indicate that occupants in the brace position do not require 
supplemental protection, and so it would not be necessary to show that 
inflatable lapbelts will enhance the brace position.

[[Page 36087]]

However, the inflatable lapbelts must not introduce any hazards when 
they deploy into seated, braced occupants.
    Another area of concern is children in these seats whether lap-
held, in approved child safety seats, or occupying the seat directly. 
Although specifically prohibited by the FAA operating regulations, the 
use of the supplementary loop belt (``belly belt'') may be required by 
other civil aviation authorities, and should also be considered with 
the end goal of meeting those regulations. Similarly, if the seat is 
occupied by a pregnant woman, the installation needs to address such 
usage, either by demonstrating that it will function properly, or by 
adding appropriate limitation on usage.

No Resulting Hazards From Proper Functioning

    To be an effective safety system, inflatable lapbelts must function 
properly and must not introduce any additional hazards to occupants as 
a result of their functioning. There are several areas where inflatable 
lapbelts differ from traditional occupant protection systems and 
require special conditions to ensure adequate performance.
    Inflatable lapbelts are essentially single-use devices. As a 
result, they could potentially deploy under crash conditions that are 
not sufficiently severe as to require head injury protection from the 
inflatable lapbelts. Since crashes are frequently composed of a series 
of impacts before the airplane comes to rest, if a larger impact 
follows the initial impact, the inflatable lapbelts could be rendered 
useless. Other safety devices such as energy absorbing pads or upper 
torso restraints tend to provide continuous protection regardless of 
severity or number of impacts in a crash event. Therefore, the 
inflatable lapbelts should provide protection when required and they 
should not expend their protection during a less severe impact. Also, 
it is possible to have several large impact events during the course of 
a crash, but there will be no requirement for the inflatable lapbelts 
to provide protection for multiple impacts.
    Each occupant's restraint system is designed to provide protection 
for only that occupant. However, unoccupied seats that may have active 
lapbelts are also a concern. It will be necessary to show that the 
required protection is provided for each occupant, regardless of the 
number of occupied seats.

Impact on Egress

    Since the inflatable lapbelts likely have a large volume 
displacement, the inflated bags could potentially impede egress of 
passengers. Since the bags deflate to absorb energy, it is likely that 
the inflatable lapbelts would be deflated at the time that persons 
would be trying to leave their seats. Nonetheless, it is appropriate to 
specify a time interval after which the inflatable lapbelts may not 
impede rapid egress. Ten seconds has been chosen as a reasonable time, 
since this corresponds to the maximum time allowed for an exit to be 
opened (in accordance with Sec.  25.809). In actuality, it is unlikely 
that a flight attendant would be able to prepare an exit this quickly, 
especially in an accident that is severe enough to deploy the 
inflatable lapbelts. Furthermore, the inflatable lapbelts will likely 
deflate much more quickly than ten seconds.
    It is even more critical that the inflatable lapbelts do not impede 
rapid egress in the emergency exit row seats. Section 25.813 clearly 
requires that there must be an unobstructed passageway from the main 
aisle to the exit and that there must be no interference in opening the 
exit. The restraint system must not impede access to and the opening of 
the exit. In some cases, such as a Type III over-wing hatch, a 
passenger is the one who will open the exit. These lapbelts should be 
evaluated in the exit row under existing regulations (Sec. Sec.  25.809 
and 25.813) and guidance material. The inflatable lapbelts must also be 
evaluated in post-crash conditions. They should be evaluated using 
representative restraint systems in the bag deployed condition.
    This evaluation includes reviewing the access to and opening of the 
exit, specifically looking for obstructions in the egress path and any 
interference in opening the exit. Each unique interior configuration 
must be considered (e.g., passageway width and single, or dual 
passageways with the outboard seat removed). If restraints create any 
obstruction or interference, they could impede rapid egress. If these 
restraint systems are installed at exit door rows, it is likely that 
project-specific guidance will be necessary.

Availability When Needed

    These special conditions include requirements to ensure that 
inflatable lapbelts operate in the aviation environment. These special 
conditions also incorporate requirements to ensure that the inflatable 
lapbelts are protected from HIRF and meet the requirements of Sec.  
25.1316. Existing regulations regarding lightning, Sec.  25.1316, and 
the existing HIRF special condition for the Boeing Model 717-200 series 
aircraft, Special Conditions No. 25-ANM-60 (57 FR 34511, August 5, 
1992), are also applicable.
    Since inflatable lapbelts will be electrically powered, the system 
could possibly fail if the fuselage separates. Since this system is 
intended as crash/post-crash protection means, failure due to fuselage 
separation is not acceptable. As with emergency lighting, the system 
should function properly if such a separation occurs at any point in 
the fuselage. Inflatable lapbelts will rely on electronic sensors for 
signaling and pyrotechnic charges for activation so that they are 
available when needed.

Prevention of Inadvertent Activation

    Inflatable lapbelts could be susceptible to inadvertent activation, 
causing them to deploy in a potentially unsafe manner. The consequences 
of such deployment must be considered in establishing the reliability 
of the system. Therefore, Boeing must substantiate that if the lapbelts 
inadvertently deploy, they will not create a hazard to the airplane. If 
this cannot be substantiated, then Boeing must demonstrate that 
inadvertent deployment is an extremely improbable occurrence (i.e., 
less than 10-9 per flight hour). Also, if the lapbelts are 
inadvertently deployed, the effects on passengers or crew members who 
are standing or sitting close by should also be considered. A minimum 
reliability level will have to be established for this case, depending 
upon the consequences, even if the effect on the airplane is 
negligible.
    In-service and outside environmental conditions could increase the 
potential for inadvertent activation. The cumulative effects of wear 
and tear must also be considered so that it does not increase the 
likelihood of an inadvertent deployment to an unacceptable level. To 
mitigate the effects of such cumulative damage, it is necessary to 
develop an appropriate inspection interval and self-test capability. 
Environmental conditions, such as lightning and HIRF, could potentially 
affect inflatable lapbelt systems. To demonstrate compliance in such 
conditions, it is first necessary to determine whether the lapbelts are 
critical or essential systems. If inadvertent deployment could cause a 
hazard to the airplane, inflatable lapbelts are considered a critical 
system; if inadvertent deployment could cause injuries to persons, the 
inflatable lapbelts are considered an essential system. Finally, the 
inflatable lapbelt installation should be protected from the effects of 
fire, so, for example, a rupture of the pyrotechnic squib does not 
create an additional hazard.

Flammability

    Special Conditions No. 25-187-SC (66 FR 52017, October 12, 2001) 
issued

[[Page 36088]]

for the Boeing Model 777 series airplanes was the first special 
conditions to address flammability of the airbag material. The Boeing 
Model 717-200 series airplanes will use the similar airbag material in 
their inflatable lapbelts. During the development of inflatable 
lapbelts, the manufacturer was unable to develop a fabric that would 
meet the inflation requirements for the bag and the flammability 
requirements of part I(a)(1)(ii) of appendix F to part 25. The fabrics 
that were developed that meet the flammability requirement did not 
produce acceptable deployment characteristics. However, the 
manufacturer was able to develop a fabric that meets the less stringent 
flammability requirements of part I(a)(1)(iv) of appendix F to part 25 
and has acceptable deployment characteristics.
    Part I of appendix F to part 25 specifies the flammability 
requirements for interior materials and components. Appendix F does not 
explicitly reference inflatable restraint systems, because they did not 
exist when the flammability requirements were written. The existing 
requirements are based on both material types, as well as use, and have 
been specified in light of the state-of-the-art materials available to 
perform a given function. In the absence of a specific reference, the 
default requirement would be for the type of material used to construct 
the inflatable restraint, which is a fabric in this case. However, in 
issuing special conditions, the FAA must also consider the use of the 
material and whether the default requirement is appropriate. In this 
case, the specialized function of the inflatable restraints means that 
highly specialized materials are needed.
    The standard normally applied to fabrics is a 12-second vertical 
ignition test. However, materials that meet this standard do not 
perform adequately as inflatable restraints. Since the safety benefits 
of the inflatable restraints are very significant, the flammability 
standard appropriate for these devices should not screen out suitable 
materials, thereby effectively eliminating use of inflatable 
restraints. The FAA will need to establish a balance between the safety 
benefit of the inflatable restraints and flammability performance. At 
this time, the 2.5-inch per minute horizontal test is considered to 
provide that balance. As materials standards and technology change 
(which is expected), the FAA may change this standard in subsequent 
special conditions to account for improved materials.
    As discussed previously, the following special conditions can be 
characterized as addressing either the safety performance of the system 
or the system's integrity against inadvertent activation. Because a 
crash requiring use of the inflatable lapbelts is a relatively rare 
event, and because the consequences of an inadvertent activation are 
potentially quite severe, these latter requirements are probably the 
more rigorous from a design standpoint.
    Finally, it should be noted that the special conditions are 
applicable to the inflatable lapbelt system as installed. The special 
conditions are not an installation approval. Therefore, while the 
special conditions relate to each such system installed, the overall 
type certificate or supplemental type certificate approval is a 
separate finding and must consider the combined effects of all such 
systems installed. For the reasons discussed above, 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.

Applicability

    As discussed above, these special conditions are applicable to the 
Model 717-200 series airplanes. Should Boeing apply at a later date for 
a change to the type certificate to include another model incorporating 
the same novel or unusual design feature, the special conditions would 
apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on one model series of airplanes. It is not a rule of general 
applicability.
    The substance of these special conditions has been subjected to the 
notice and comment period in several prior instances and has been 
derived without substantive change from those previously issued. It is 
unlikely that prior public comment would result in a significant change 
from the substance contained herein. Therefore, the FAA has determined 
that prior public notice and comment are unnecessary and good cause 
exists for adopting these special conditions upon issuance. The FAA is 
requesting comments to allow interested persons to submit views that 
may not have been submitted in response to the prior opportunities for 
comment described above.

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 717-200 series airplanes 
equipped with inflatable lapbelts.
    1. Seats with Inflatable Lapbelts. It must be shown that the 
inflatable lapbelt will deploy and provide protection under crash 
conditions where it is necessary to prevent serious head injury. The 
means of protection must take into consideration a range of stature 
from a two-year-old child to a ninety-fifth percentile male. The 
inflatable lapbelt must provide a consistent approach to energy 
absorption throughout that range of occupants. In addition, the 
following situations must be considered:
    a. The seat occupant is holding an infant.
    b. The seat occupant is a child in a child restraint device.
    c. The seat occupant is a child not using a child restraint device.
    d. The seat occupant is a pregnant woman.
    2. The inflatable lapbelt must provide adequate protection for each 
occupant regardless of the number of occupants of the seat assembly, 
considering that unoccupied seats may have active seatbelts.
    3. The design must prevent the inflatable lapbelt from being either 
incorrectly buckled or incorrectly installed such that the inflatable 
lapbelt would not properly deploy. Alternatively, it must be shown that 
such deployment is not hazardous to the occupant, and will provide the 
required head injury protection.
    4. It must be shown that the inflatable lapbelt system is not 
susceptible to inadvertent deployment as a result of wear and tear, or 
inertial loads resulting from in-flight or ground maneuvers (including 
gusts and hard landings), and other operating and environmental 
conditions (vibrations, moisture, etc.) likely to be experienced in 
service.
    5. Deployment of the inflatable lapbelt must not introduce injury 
mechanisms to the seated occupant, or result in injuries that could 
impede rapid egress. This assessment should include an occupant who is 
in the brace position when it deploys and an occupant whose belt is 
loosely fastened.
    6. It must be shown that inadvertent deployment of the inflatable 
lapbelt, during the most critical part of the flight, will either not 
cause a hazard to

[[Page 36089]]

the airplane or its occupants, or it meets the requirement of Sec.  
25.1309(b).
    7. It must be shown that the inflatable lapbelt will not impede 
rapid egress of occupants 10 seconds after its deployment.
    8. The system must be protected from lightning and high intensity 
radiomagnetic fields (HIRF). The threats specified in existing 
regulations regarding lightning, Sec.  25.1316, and existing HIRF 
special conditions for the Boeing Model 717-200 series airplanes, 
Special Conditions No. 25-ANM-60, are incorporated by reference for the 
purpose of measuring lightning and HIRF protection.
    9. Inflatable lapbelts, once deployed, must not adversely affect 
the emergency lighting system (e.g., block proximity lights to the 
extent that the lights no longer meet their intended function).
    10. The inflatable lapbelt must function properly after loss of 
normal aircraft electrical power, and after a transverse separation of 
the fuselage at the most critical location. A separation at the 
location of the lapbelt does not have to be considered.
    11. It must be shown that the inflatable lapbelt will not release 
hazardous quantities of gas or particulate matter into the cabin.
    12. The inflatable lapbelt installation must be protected from the 
effects of fire such that no hazard to occupants will result.
    13. There must be a means for a crew member to verify the integrity 
of the inflatable lapbelt activation system prior to each flight, or it 
must be demonstrated to reliably operate between inspection intervals. 
The FAA considers the loss of the airbag system deployment function 
alone (i.e., independent of the conditional event that requires the 
airbag system deployment) to be a major failure condition.
    14. The inflatable material may not have an average burn rate of 
greater than 2.5 inches/minute when tested using the horizontal 
flammability test as defined in 14 CFR part 25, appendix F, part I, 
paragraph (b)(5).

    Issued in Renton, Washington, on June 12, 2013.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-14322 Filed 6-14-13; 8:45 am]
BILLING CODE 4910-13-P
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