81 FR 45965 - Special Conditions: Cirrus Design Corporation, Model SF50; Whole Airplane Parachute Recovery System

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 81, Issue 136 (July 15, 2016)

These special conditions are issued for the Cirrus Design Corporation (Cirrus), model SF50 airplane. This airplane will have a novel or unusual design feature(s) associated with a whole airplane parachute recovery system. 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.

[Federal Register Volume 81, Number 136 (Friday, July 15, 2016)]
[Rules and Regulations]
[Pages 45965-45968]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2016-16813]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 23

[Docket No. FAA-2016-3462; Notice No. 23-275-SC]


Special Conditions: Cirrus Design Corporation, Model SF50; Whole 
Airplane Parachute Recovery System

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions.

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SUMMARY: These special conditions are issued for the Cirrus Design 
Corporation (Cirrus), model SF50 airplane. This airplane will have a 
novel or unusual design feature(s) associated with a whole airplane 
parachute recovery system. 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: These special conditions are effective August 15, 2016 and are 
applicable on July 6, 2016.

FOR FURTHER INFORMATION CONTACT: Mr. Bob Stegeman, Federal Aviation 
Administration, Aircraft Certification Service, Small Airplane 
Directorate, ACE-111, 901 Locust; Kansas City, Missouri 64106; 
telephone (816) 329-4140; facsimile (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Background

    On September 9, 2008, Cirrus Design Corporation applied for a type 
certificate for their new SF50 airplane. The SF50 is a seven seat (five 
adults and two children), pressurized, retractable gear, carbon 
composite, single engine jet airplane. The airplane will have a Maximum 
Take-Off Weight of 6,000 pounds, a Maximum Operating Speed of 250 Knots 
Calibrated Airspeed (KCAS), and a Maximum Operating Altitude of 28,000 
feet.
    Cirrus intends to install a whole airplane ballistic parachute 
system (BPS) called the Cirrus Airframe Parachute System (CAPS). This 
installation couples the BPS with the automatic flight controls. The 
CAPS will be installed as standard equipment on the SF50 airplane. 
Unlike the SR20 and SR22 airplanes CAPS, the SF50 CAPS is a 
supplemental system and no credit for the system will be used to meet 
part 23 requirements. The SF50 CAPS design will require some 
performance enhancements over existing technology used in other BPS.
    The system will consist of the recovery parachute, activation and 
deployment systems, and autopilot functions. The SF50 CAPS will be 
designed for a higher gross weight, maximum activation speed, and 
maximum operating altitude.
    Whole airplane parachute recovery systems are intended to save the 
lives of the occupants in life-threatening situations for which normal 
emergency procedures have been exhausted. Potential emergencies 
include, but are not limited to--loss of power or thrust; loss of 
airplane control; pilot disorientation; pilot incapacitation with a 
passenger on board; mechanical or structural failure; icing; and 
accidents resulting from pilot negligence or error. The recovery system 
should prioritize protection from most probable hazards, but it is not 
reasonable to expect it to protect occupants from every possible 
situation.
    This technology, which was originally developed for ultralight and 
experimental aircraft, was first approved for general aviation 
airplanes with a Supplemental Type Certificate for the Cessna model 
150/152 airplanes. The FAA issued special conditions for these 
airplanes to incorporate ballistic recovery systems on October 22, 1987 
(Special Condition No. 23-ACE-33; Ballistic Recovery System, Inc., 
Modified Cessna 150/A150 Series Airplanes and 152/A152 Model Airplanes 
to Incorporate the GARD-150 System; Docket No. 037CE) (FR Doc. 87-
26420, November 11, 1987). These special conditions were later modified 
for the other general aviation airplanes (Special Condition No. 23-ACE-
76; Ballistic Recovery Systems, Modified for Small General Aviation 
Airplanes; Docket No. 118CE) (FR Doc. 94-16233, August 5, 1994), 
including the Cirrus Design Corporation SR20 airplanes (Special 
Condition No. 23-ACE-88, Ballistic Recovery Systems Cirrus SR20 
Installation, Docket No. 136CE) (FR Doc. 97-27504, October 15, 1997).
    The previously FAA-approved BPS consists of a parachute packed in a 
compartment within the airframe. A solid propellant rocket motor, 
adjacent to the parachute pack, extracts the parachute. A mechanical 
pull handle mounted within reach of the pilot and copilot or passenger 
activates the system. At least two separate independent actions are 
necessary to activate the system.
    In addition to a normal BPS, the SF50 CAPS system will incorporate 
an airbag to assist deployment and a system for sequencing deployment 
and interfacing with the airplane's avionics. The avionics interface is 
intended to bring the airplane within a valid deployment envelope speed 
(67-160 KCAS).
    The SF50 CAPS is a non-required system that differs from other BPS 
in that it will interact with the flight control system and other 
airplane systems. The baseline special conditions must incorporate the 
required level of safety for the normal BPS as well as the aspect that 
interfaces with the airplane. Since it is a non required system, 
additional latitude exists to evaluate and substantiate the system so 
it will present no additional hazards.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Cirrus Design Corporation 
must show that the SF50 meets the applicable provisions of part 23, as 
amended by amendments 23-1 through 23-62 thereto.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 23) do not contain adequate or 
appropriate safety standards for the SF50 because of a novel or unusual 
design feature, special conditions are prescribed under the provisions 
of Sec.  21.16.
    In addition to the applicable airworthiness regulations and special 
conditions, the SF50 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 and the FAA must issue a finding of 
regulatory adequacy under section 611 of Public Law 92-574, the ``Noise 
Control Act of 1972.''
    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.  21.17(a)(2).
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same or similar 
novel or unusual design feature, the special conditions would also 
apply to the other model under Sec.  21.101.

[[Page 45966]]

Novel or Unusual Design Features

    The SF50 will incorporate the following novel or unusual design 
features: A whole-airplane parachute recovery system that is a 
supplemental safety system and unlike any previously approved BPS, will 
add enhancements that assist deployment and autopilot functions that 
work to bring the airplane into an acceptable deployment envelope.

Discussion

    This system is a non-required system that will interact with the 
flight control system. These special conditions must incorporate the 
required level of safety for the normal ballistic parachute system as 
established by Special Condition 23-ACE-76 in addition to the aspect 
that interfaces with the airplane.
    The FAA revised Sec.  23.1309, Equipment, systems, and 
installations, in amendment 23-62 (76 FR 75736, December 2, 2011) to 
address two different types of equipment and systems installed in the 
airplane. This system operates at the limit of the normal operating 
envelope and challenges normal expectations of such a supplemental 
system. Amendment 23-62 preamble states: Section 23.1309 lists the 
qualifiers ``under the airplane operating and environmental 
conditions''.
    Section 23.1309, amendment 23-62 preamble also describes two 
actions for the applicant. First, the applicant must consider the full 
normal operating envelope of the airplane, as defined by the Airplane 
Flight Manual, with any modification to that envelope associated with 
abnormal or emergency procedures and any anticipated flightcrew action. 
Second, the applicant must consider the anticipated external and 
internal airplane environmental conditions, as well as any additional 
conditions where equipment and systems are assumed to ``perform as 
intended''.
    Section 23.1309(a)(2) requires analysis of any installed equipment 
or system with potential failure conditions that are catastrophic, 
hazardous, major, or minor, to determine their impact on the safe 
operation of the airplane. The applicant must show that they do not 
adversely affect proper functioning of the equipment, systems, or 
installations covered by Sec.  23.1309 and do not otherwise adversely 
influence the safety of the airplane or its occupants.
    Section 23.1309(a)(2) does not mandate that non-required equipment 
and systems function properly during all airplane operations once in 
service, provided all potential failure conditions have no effect on 
the safe operation of the airplane. The equipment or system must 
function in the manner expected by the manufacturer's operating manual 
for the equipment or system. An applicant's statement of intended 
function must be sufficiently detailed so the FAA can evaluate whether 
the system is appropriate for its intended function(s).
    To incorporate the intent of amendment 23-62, the FAA issues these 
special conditions to include previous BPS special conditions, address 
the interaction CAPS with other airplane systems, and that it is a non-
required system. The system must function within specified 
manufacturer's limits while operated within the manufacturers 
recommended envelope. Since it is a non-required system, the means of 
substantiation have been altered to reflect the bounds of the operating 
envelope, the means of analysis that can be substantiated with 
overlapping lower-level testing/analysis, and relieve in-flight 
deployment to avoid unnecessary expense and the inherent danger in 
performing this test.
    All special condition requirements must meet two fundamental 
criteria:
     The installed system must not introduce unacceptable 
hazards prior to or after activation.
     The applicant must show that the system does not adversely 
affect proper functioning of the equipment, systems, or installations 
covered by Sec.  23.1309 and do not otherwise adversely influence the 
safety of the airplane or its occupants.

The applicant does not have to demonstrate the system in flight on a 
test airplane.

Discussion of Comments

    Notice of proposed special conditions No. 23-16-01-SC for the 
Cirrus Design Corporation SF50 airplanes was published in the Federal 
Register on March 18, 2016 (81 FR 14801). The FAA received 11 comments 
that disagreed with the special condition provisions for demonstration 
via test or test supported by analysis. These comments primarily 
focused on the concern that the FAA should require testing of the BPS 
in flight to validate intended performance.
    The process of an applicant showing compliance to these BPS system 
special conditions is a complex and multi-tiered process. The applicant 
must conservatively demonstrate each function of the entire deployment 
event sequentially, from pulling the handle to securing the airplane 
after ground impact, to meet the special conditions. These separate 
events and functions can be demonstrated to satisfy the requirements of 
these special conditions with lower-level testing, normally using 
analysis supported by test. This is consistent with certification 
methods used on many other parts of the airplane.
    The FAA decision to allow a means of compliance without requiring 
inflight deployment on a test airplane is not a complete elimination of 
testing or an evaluation of the system. The FAA believes that test or 
analysis supported by test will provide an acceptable level of safety 
to demonstrate that the system will perform its intended function; 
therefore, no in-flight deployment on a test airplane will be required.
    The Cirrus SF50 BPS is a non-required safety device intended to 
improve occupant survivability in emergencies and under extreme 
conditions. The certification requirements contained in these special 
conditions are consistent with the requirements of Sec. Sec.  
23.1301(a) and 23.1309(a) for equipment that is not required for type 
certification or by the operating rules. Because the BPS is non-
required equipment, its design must be shown to be appropriate for the 
intended function and it must not adversely affect safety. The FAA 
Aircraft Certification Service has evaluated the intended function, 
design, and installation of the SF50 BPS, and has considered what is 
required to meet an acceptable confidence level.
    The potential operational decision to deploy the BPS in service 
would be the result of an emergency, one that will invariably result in 
a controlled crash. While the BPS is expected to improve occupant 
survivability in an emergency, the residual risk to the occupants is 
not completely eliminated. The primary hazard introduced while 
performing a comprehensive BPS flight test is the risk to the flight 
test crew when exposed to controlled crash conditions during a 
successful deployment. The FAA has determined the requirement to 
demonstrate the BPS via testing or testing supported by analysis to be 
``appropriate for the intended function and does not adversely affect 
safety''. Therefore, the FAA will not require a comprehensive flight 
test deployment.
    Another commenter requested clarification of paragraph 1(c)(3), 
regarding definition of occupant protection after aircraft structure 
damage. To clarify, the FAA's intent of this paragraph was to ensure 
that the cabin can protect the occupants after a normal deployment even 
if the cabin experiences damage resulting from the deployment process 
or as a result of ground impact. The paragraph does not

[[Page 45967]]

assume any airplane damage prior to system deployment.

Applicability

    As discussed above, these special conditions are applicable to the 
SF50. Should Cirrus 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 standard practice, the effective date of final special 
conditions would be 30 days after the date of publication in the 
Federal Register; however, as the certification date for the Cirrus 
SF50 is imminent, the FAA finds that good cause exists to make these 
special conditions effective upon issuance.

Conclusion

    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, 44701, 14 CFR 11.38, 11.39, 
21.16 and 21.17.

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 Cirrus SF50 airplanes.
    1. Whole Airplane Parachute Recovery System With Flight Control and 
Deployment Augmentation.
    (a) System Validation.
    (1) The applicant must demonstrate by test, or analysis supported 
by test, that the system will not cause an unacceptable hazard or 
otherwise exceed the system deployment design loads for the critical 
flight conditions.
    (2) The recovery system activation envelope must include speeds at 
or near VS up to at least Vo. The applicant must 
satisfactorily demonstrate by test, or by analysis supported by test, 
the logic and automatic control interface that allow the recovery 
system activation over this speed range.
    (b) Occupant Restraint.
    Each seat in the airplane must be equipped with an approved 
restraint system, which will protect the occupants from serious head 
and upper torso injuries during a recovery system deployment and ground 
impact at the critical load conditions.
    (c) Parachute Performance.
    (1) A 1.5 factor of safety applied to the limit load must be used 
for all components of the recovery system as well as the attachment 
structure, the cabin structure surrounding the occupants, and any 
interconnecting structure of the airplane. Limit loads are defined as 
the parachute deployment forces developed within the operational 
envelope of the system. Lower factors of safety for airplane weight and 
velocity may be used, so that when combined in the energy equation, 
represent a 1.5 factor of safety of the energy equation.
    (2) Stitching must be of a type that will not ravel when broken.
    (3) The applicant must show via test, or analysis supported by 
test, that with the recovery parachute deployed and the airplane 
structure damaged, the airplane impact during touchdown will result in 
an occupant environment in which serious injury to the occupants is 
improbable.
    (4) The applicant must show via test, or analysis supported by 
test, that with the recovery parachute deployed, the airplane can 
impact the ground in various adverse weather conditions, including 
winds up to 15 knots, without endangering the airplane occupants at and 
after touchdown.
    (d) System Function and Operations.
    (1) The installation design and location of the extraction device 
must consider fire hazards associated with the activation of the 
parachute system and reduce this potential as much as possible without 
compromising function of the extraction device.
    (2) A system safety analysis will be conducted on the recovery 
system that will consider the effects of annunciated and un-annunciated 
failures. This analysis will address both losses of function as well as 
malfunction (including un-commanded system activation). The applicant 
must show that they do not adversely affect proper functioning of the 
equipment, systems, or installations covered by Sec.  23.1309, and do 
not otherwise adversely influence the safety of the airplane or its 
occupants. It must be shown that reliable and functional deployment in 
the adverse weather conditions that the airplane is approved for have 
been considered. For example, if the airplane is certified for flight 
in icing conditions, and flight test in icing reveals that ice may 
cover the deployment area, then the possible adverse effects of ice or 
an ice layer covering the parachute deployment area should be analyzed.
    (3) The recovery system must be designed to safeguard against 
inadvertent activation. Two separate and intentional actions will be 
required to activate the system.
    (4) It must be demonstrated that the system can be activated 
without difficulty by occupants of various sizes, from a 10th 
percentile female to a 90th percentile male, while sitting in the pilot 
or copilot seat.
    (5) The system must be labeled for identification, function, and 
operating limitations.
    (6) The airplane must be equipped with ASTM F 2316-06 conforming 
placards suitable to draw attention of first responders. Section 11 of 
ASTM F 2316-06, specifies that the airplane should be marked with a 
``danger'' placard placed adjacent to the exit point of each rocket/
parachute, an ``identifying'' placard attached to each rocket, and 
``warning'' placard(s) applied where occupant(s) enter the airplane or 
where rescue personnel can readily see the placard(s).
    (e) Design and Construction.
    (1) All components of the system must be protected against 
deterioration due to weathering, corrosion, and abrasion.
    (2) Adequate provisions must be made for ventilation and drainage 
of the system compartments and associated structure to ensure the sound 
condition of the system.
    (f) Materials and workmanship.
    (1) The suitability and durability of materials used for parts, the 
failure of which could adversely affect safety, must--
    i. Be established by experience or tests;
    ii. Meet approved specifications that ensure their having the 
strength and other properties assumed in the design data; and
    iii. Take into account the effects of environmental conditions, 
such as temperature and humidity, expected in service.
    (2) Workmanship must be of a high standard.
    (3) The parachute(s) must be identified with a data panel that 
defines the Manufacturer, Date of Manufacture, Part Number, and Serial 
Number.
    (g) Systems Maintenance and Inspection.
    (1) Instructions for continued airworthiness must be prepared for 
the system that meet the requirements of Sec.  23.1529.
    (2) Adequate means must be provided to permit the close examination 
of the system components to ensure proper functioning, alignment, 
lubrication, and adjustment during the required inspection of the 
system.

[[Page 45968]]

    (h) Operating Limitations.
    (1) Operating limitations must be prescribed to ensure proper 
operation of the system. A detailed discussion of the system, including 
operation, limitations, and deployment envelope must be included in the 
Airplane Flight Manual.
    (2) Operating limitations must be prescribed for inspecting and 
overhauling the system components at approved intervals.

    Issued in Kansas City, Missouri, on July 6, 2016.
William Schinstock,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-16813 Filed 7-14-16; 8:45 am]
BILLING CODE 4910-13-P