Special Conditions: Sino Swearingen, Model SJ30-2; Side-Facing Seat

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed special conditions.

SUMMARY:

This action proposes special conditions for the Sino Swearingen, Model SJ30-2 airplane. This airplane will have a novel or unusual design feature(s) associated with side-facing seats. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These proposed 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:

Comments must be received on or before October 20, 2000.

ADDRESSES:

Comments on this proposal may be mailed in duplicate to: Federal Aviation Administration, Regional Counsel, ACE-7, Attention: Rules Docket, Docket No. CE163, 901 Locust, Room 506, Kansas City, Missouri 64106, or delivered in duplicate to the Regional Counsel at the above address. Comments must be marked: CE163. Comments may be inspected in the Rules Docket weekdays, except Federal holidays, between 7:30 a.m. and 4:00 p.m.

FOR FURTHER INFORMATION CONTACT:

Les Taylor, Federal Aviation Administration, Aircraft Certification Service, Small Airplane Directorate, ACE-111, 901 Locust, Room 301, Kansas City, Missouri, 816-329-4134, fax 816-329-4090.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of these proposed special conditions by submitting such written data, views, or arguments as they may desire. Communications should identify the regulatory docket or notice number and be submitted in duplicate to the address specified above. The Administrator will consider all communications received on or before the closing date for comments. The proposals described in this action may be changed in light of the comments received. All comments received will be available in the Rules Docket for examination by interested persons, both before and after the closing date for comments. A report summarizing each substantive public contact with FAA personnel concerning this rulemaking will be filed in the docket. Persons wishing the FAA to acknowledge receipt of their comments submitted in response to this action must include with those comments a self-addressed, stamped postcard on which the following statement is made: “Comments to CE163.” The postcard will be date stamped and returned to the commenter.

Background

On October 9, 1995, Sino Swearingen Aircraft Company, 1770 Sky Place Boulevard, San Antonio, Texas 78216, applied for normal category type certificate for their new Model SJ30-2. The Model SJ30-2 airplane is a six-to-eight place, all metal, low-wing, T-tail, twin turbofan engine powered airplane with fully enclosed retractable landing gear. The SJ30-2 will have a VMO/MMO of 320 knots/M=.83, and will have engines mounted aft on the fuselage.

The Model SJ30-2 airplane will contain one side-facing seat. Side facing seats are considered a novel design and were not considered when those airworthiness standards were promulgated. The FAA has determined that the existing regulations do not provide adequate or appropriate safety standards for occupants of side-facing single occupant seats. In order to provide a level of safety that is equivalent to that afforded to occupants of forward and aft facing seats, additional airworthiness standards, in the form of additional special conditions, are necessary.

Type Certification Basis

Under the provisions of 14 CFR 21.17, Sino Swearingen Aircraft Company must show that the Model SJ30-2 meets the applicable provisions of 14 CFR part 23 as amended by Amendments 23-1 through 23-53, and selected portions of 14 CFR part 25 as provided for by 14 CFR part 21, §§ 21.16 and 21.17(a)(2); exemptions, if any; equivalent level of safety findings, if any; and the special conditions adopted by this rulemaking action.

If the Administrator finds that the applicable airworthiness regulations (i.e., part 23) do not contain adequate or appropriate safety standards for the Sino Swearingen Model SJ30-2 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 Model SJ30-2 must comply with the part 23 fuel vent and exhaust emission requirements of 14 CFR part 34 and the noise certification requirements of 14 CFR part 36, and the FAA must issue a finding of regulatory adequacy pursuant to section 611 of Public Law 92-574, the “Noise Control Act of 1972.”

Special conditions, as appropriate, are issued in accordance with § 11.49 after public notice, as required by §§ 11.28 and 11.29(b), and become part of the type certification basis in accordance with § 21.17(a)(2).

Novel or Unusual Design Features

The Model SJ30-2 will incorporate the following novel or unusual design features: A side-facing seat occupiable for taxi, takeoff and landing.

FAA Position

The intent of these special conditions is to establish a level of safety for the occupant of the side facing seat consistent with the level afforded occupants of the forward and aft facing seats. The primary objective is that all occupants should have protection from serious injuries, regardless of the orientation of the seat system. Occupants of side facing seats are exposed to different physical loads than forward facing occupants, such as lateral body contact with armrests and walls. Thus, a means to assess the potential for injuries due to occupant loads imparted by lateral impacts must be imposed.

Therefore, the following special conditions are considered to be applicable to the side facing seat on the SJ30-2.

In addition to the airworthiness standards in §§ 23.562 and 23.785, the following special conditions provide the additional injury criteria and installation/testing guidelines that represent the minimum acceptable airworthiness standards for side facing seats:

1. Injury Criteria

(a) Existing Criteria: All injury protection criteria of § 23.562(c)(1) through (c)(7) and § 23.785 apply to the occupant of a side facing seat. Head Injury Criteria (HIC) assessments are only required for head contact with either the seat or adjacent structures or both.

(b) Body-to-wall/furnishing contact: The seat must be installed aft of a structure such as an interior wall or furnishing that will support the pelvis, upper arm, chest, and head of an occupant seated next to the structure. Horizontal tests of the seat must include representative structures for the forward wall. The wall must include attachments that represent the geometry, strength, and stiffness of the airplane installation. If there are structures forward of the wall that will affect the deformation of the wall, these structures must be addressed in the test procedure. The contact surface of this structure must be covered with at least two inches of energy absorbing protective foam, such as ensolite.

(c) Thoracic Trauma: Testing with a Side Impact Dummy (SID), as defined by 49 CFR part 572, Subpart F, or its equivalent, must be conducted and Thoracic Trauma Index (TTI) injury criteria acquired with the SID must be less than 85, as defined in 49 CFR part 572, Subpart F. SID TTI data must be processed as defined in Federal Motor Vehicle Safety Standard (FMVSS) § 571.214, S 6.13.5. Rational analysis, comparing an installation with another installation where TTI data were acquired and found acceptable, may also be viable.

(d) Pelvis: Pelvic lateral acceleration must not exceed 130g. Pelvic acceleration data must be processed as defined in FMVSS § 571.214, S 6.13.5.

2. General Test Guidelines

(a) One test with the SID Anthropomorphic Test Dummy (ATD), undeformed floor, no yaw, and with all lateral structural supports (armrests/walls).

Pass/fail injury assessments: TTI; and pelvic acceleration.

(b) One test with the Hybrid II ATD, or equivalent, deformed floor, with 10 degrees yaw, and with all lateral structural supports (armrests/walls). Pass/fail injury assessments: HIC; and upper torso restraint system retention and pelvic acceleration.

(c) Vertical test to be conducted with modified Hybrid II ATD's with existing pass/fail criteria.

Applicant's Position

The intent of the criteria established is to provide an equivalent level of safety to that afforded to forward and aft facing seats. The applicant concurs that the test guidelines and injury criteria defined achieve that goal with the following exceptions and clarifications.

1. In the assessment of the TTI and pelvic lateral accelerations for the test condition defined in Item 2(a), the applicant proposes to retain the option of using either the SID ATD as defined or, alternately, the EuroSID ATD as defined by the Official Journal of European Communities, L169 Volume 39, dated July 8, 1996, Directive 96/27/EC and amending Directive 70/156/EEC. The applicant considers both the SID and the EuroSID to be acceptable ATD's for the showing of compliance with the requirements of Item 2(a).

2. The designation of “seat/restraint systems * * * installed in the first row” given in § 23.562 is applied to the crew seats located on the flight deck. The designation of “all other seat/restraint systems” given in § 23.562 is applicable to all SJ30-2 seats other than those located on the flight deck. Therefore, the test conditions of Items 2(a) and 2(b) shall be in accordance with the 21G pulse defined in § 23.562(b)(2) with the exceptions noted, and the test conditions of Item 2(c) shall be in accordance with the 15G pulse defined in § 23.562(b)(1) with the exceptions noted.

Applicability

As discussed above, these special conditions are applicable to the Model SJ30-2. Should Sino Swearingen Aircraft Company 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 under the provisions of § 21.101(a)(1).

Conclusion

The special conditions proposed in the FAA position are acceptable. The conditions requested by the applicant are as follows:

1. The EuroSID-1 ATD as defined in the Applicant's Position is considered an acceptable equivalent for the purposes of the tests defined in these special conditions.

2. The applicants position which is consistent with Advisory Circular 23.562-1, page 4, shows a table in which “crew” seats are shown to meet the 19/26G pulses and passenger seats are shown to meet the 15/21 G pulses.

This action affects only certain novel or unusual design features on one model of airplane. It is not a rule of general applicability, and it affects only the applicant who applied to the FAA for approval of these features on the airplane.

List of Subjects in 14 CFR Part 23

• Aircraft
• Aviation safety
• Signs and symbols

Citation

The authority citation for these special conditions is as follows:

Authority: 49 U.S.C. 106(g), 40113 and 44701; 14 CFR 21.16 and 21.17 for TC; and 14 CFR 11.28 and 11.29(b).

The Proposed Special Conditions

Accordingly, the Federal Aviation Administration (FAA) proposes the following special conditions as part of the type certification basis for the Sino Swearingen Aircraft Company Model SJ30-2 airplane applicable to side-facing seats occupiable during taxi, takeoff, and landing.

1. Injury Criteria

(a) Existing Criteria: All injury protection criteria of § 23.562(c)(1) through (c)(7) and § 23.785 apply to the occupant of a side facing seat. Head Injury Criteria (HIC) assessments are only required for head contact with either the seat or adjacent structures or both.

(b) Body-to-wall/furnishing contact: The seat must be installed aft of a structure such as an interior wall or furnishing that will support the pelvis, upper arm, chest, and head of an occupant seated next to the structure. Horizontal tests of the seat must include representative structures for the forward wall. The wall must include attachments that represent the geometry, strength, and stiffness of the airplane installation. If there are structures forward of the wall that will affect the deformation of the wall, these structures must be addressed in the test procedure. The contact surface of this structure must be covered with at least two inches of energy absorbing protective foam, such as ensolite.

(c) Thoracic Trauma: Testing with a Side Impact Dummy (SID), as defined by 49 CFR part 572, Subpart F, or its equivalent, must be conducted and Thoracic Trauma Index (TTI) injury criteria acquired with the SID must be less than 85, as defined in 49 CFR part 572, Subpart F. SID TTI data must be processed as defined in Federal Motor Vehicle Safety Standard (FMVSS) § 571.214, S 6.13.5. Rational analysis, comparing an installation with another installation where TTI data were acquired and found acceptable, may also be viable. The use of the EuroSID-1 as defined by the Official Journal of European Communities, L169 Volume 39, dated July 8, 1996, Directive 96/27/EC and amending Directive 70/156/EEC is considered acceptable for the collection of this data.

(d) Pelvis: Pelvic lateral acceleration must not exceed 130g. Pelvic acceleration data must be processed as defined in FMVSS § 571.214, S 6.13.5.

2. General Test Guidelines

(a) One test with the SID Anthropomorphic Test Dummy (ATD) or the EuroSID-1, as defined above, undeformed floor, no yaw, and with all lateral structural supports (armrests/walls).

Pass/fail injury assessments: TTI; and pelvic acceleration.

(b) One test with the Hybrid II ATD, or equivalent, deformed floor, with 10 degrees yaw, and with all lateral structural supports (armrests/walls).

Pass/fail injury assessments: HIC; and upper torso restraint system retention and pelvic acceleration.

(c) Vertical test to be conducted with modified Hybrid II ATD's with existing pass/fail criteria.

(d) G-loads used in 2(a), 2(b) and 2(c) are those defined in 14 CFR part 23, § 23.562(b), for first row (crew) and other rows (passenger) seats.