Source: https://www.federalregister.gov/documents/2012/07/23/2012-17864/special-conditions-tamarack-aerospace-group-cirrus-model-sr22-active-technology-load-alleviation
Timestamp: 2018-08-18 09:26:10
Document Index: 725623276

Matched Legal Cases: ['§\u200921', 'art 23', 'art 23', '§\u200921', 'art 35', 'art 36', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923', 'art 23', '§\u200923']

Federal Register :: Special Conditions: Tamarack Aerospace Group, Cirrus Model SR22; Active Technology Load Alleviation System (ATLAS)
42949-42952 (4 pages)
SC 23.301 Loads, Probability of Failure of Load Alleviation System
SC 23.303 Factor of Safety, Load Alleviation Systems
SC 23.571 Through SC 23.574 Fatigue and Damage Tolerance
SC 23.629 Flutter
2. Active Load Alleviation Systems—Control System Requirements.
SC 23.672 Load Alleviation Systems
https://www.federalregister.gov/d/2012-17864 https://www.federalregister.gov/d/2012-17864
These special conditions are issued for the Tamarack Aerospace Group's modification to the Cirrus SR22 airplane. This airplane as modified by Tamarack will have a novel or unusual design feature(s) associated with Tamarack Aerospace Group's modification. The design change will install winglets and an Active Technology Load Alleviation system (ATLAS). The addition of the ATLAS mitigates the negative effects of the winglets by effectively aerodynamically turning off the winglet under limit gust and maneuver loads. This is accomplished by measuring the aircraft loading and moving a small aileron-like device called a Tamarack Active Control Surface (TACS). The TACS movement reduces lift at the tip of the wing, resulting in the wing center of pressure moving inboard, thus reducing bending stresses along the wing span. 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.
For sections 23.301 through 23.629 (structural requirements), contact Mr. Mike Reyer, telephone (816) 329-4131. For sections 23.672 through 23.701 (control system requirements), contact Mr. Ross Schaller, telephone (816) 329-4162. The address and facsimile for both Mr. Reyer and Mr. Schaller is: Small Airplane Directorate, Aircraft Certification Service, 901 Locust, Kansas City, Missouri 64106; facsimile (816) 329-4090.
On February 15, 2011, Tamarack Aerospace Group applied for a supplemental type certificate for installation of winglets and an Active Technology Load Alleviation System (ATLAS) on the Cirrus Model SR22 (serial numbers 0002-2333, 2335-2419, and 2421-2437). The Cirrus Model SR22 is a certified, single reciprocating engine, four-passenger, composite airplane.
Under the provisions of § 21.101, Tamarack Aerospace Group must show that the Cirrus Model SR22, as changed, continues to meet the applicable provisions of the regulations incorporated by reference in Type Certificate Data Sheet A00009CH 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 Data Sheet A00009CH (Serial Numbers (S/Ns) 0002 through 2333, 2335 through 2419, and 2421 through 2437) are as follows:
Change in Cirrus Model SR22 certification basis for regulation 14 CFR 23.1359 through Amendment 23-49 from: Not Applicable to: Applicable
ACE-96-6 for 14 CFR Section 23.221 (Spinning); refer to FAA Memorandum, dated June 10, 1998, for Models SR20, SR22.
ACE-00-09 for 14 CFR 23.1143(g) (Engine Controls) and 23.1147(b) (Mixture Controls) Refer to FAA Memorandum, dated September 11, 2000, for Model SR22.
23-ACE-88 for ballistic parachute for Models SR20, SR22.
In addition, if the regulations incorporated by reference do not provide adequate standards regarding the change, the applicant must comply with certain regulations in effect on the date of application for the change. The FAA has determined that the Cirrus SR22 complies with the following sections of 14 CFR part 23, as amended by Amendments 23-1 through 23-61 for the areas affected by the change.
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 SR22 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 SR22 must comply with the fuel vent and exhaust emission requirements of 14 CFR part 35 and the noise certification requirements of 14 CFR part 36.
Notice of proposed special conditions No. 23-12-01-SC for the Cirrus SR22 airplanes was published on May 15, 2012 (77 FR 28530). No comments were received and the special conditions are adopted as proposed.
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 Tamarack modified Cirrus SR22 is imminent, the FAA finds that good cause exists to make these special conditions effective upon issuance.
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 Model SR22 airplanes (S/Ns 0002 through 2333, 2335 through 2419, and 2421 through 2437) modified by Tamarack Aerospace Group.
(B) In addition to the requirements in 14 CFR part 23, § 23.301 Loads, comply with the following:
(a) Failures of the load alleviation system, including the annunciation system, must be immediately annunciated to the pilot or annunciated prior to the next flight. Failure of the load alleviation system, including the annunciation system, must be no greater than 1 × 10−5 per flight hour.
(b) If failure of the load alleviation system, including the annunciation system, is greater than 1 × 10−8 per flight hour, an independent system functional test must be accomplished at a periodic interval to limit time exposure to an undetected failed system. The time interval for the system functional test must be selected so that the product of the time interval in hours and the failure of the load alleviation system, including the annunciation system, is no greater than 1 × 10−5 per hour.
(C) In place of the requirements in 14 CFR part 23, § 23.303 Factor of Safety, comply with the following:
(a) The loads resulting from 14 CFR part 23, §§ 23.321 through 23.537, as applicable, corresponding to a fully operative load alleviation system. A factor of safety of 1.5 must be applied to determine ultimate loads.
(b) If an independent system functional test is required by SC 23.301(b), the loads resulting from 14 CFR part 23, §§ 23.321 through 23.537, as applicable, corresponding to the system in the failed state without additional flight limitations or reconfiguration of the airplane. A factor of safety of 1.0 must be applied to determine ultimate loads.
(c) The loads corresponding to the time of occurrence of load alleviation system failure and immediately after the failure. These loads must be determined at any speed up to VNE, starting from 1g level flight conditions, and considering realistic scenarios, including pilot corrective actions. A factor of safety of 1.5 must be applied to determine ultimate loads.
(d) For airplanes equipped with “before the next flight” failure annunciation systems, the loads resulting from 14 CFR part 23, §§ 23.321 through 23.537, as applicable, corresponding to the system in the failed state without additional flight limitations or reconfiguration of the airplane. A factor of safety of 1.25 must be applied to determine ultimate loads.
(e) For airplanes equipped with “immediate” failure annunciation systems, the loads resulting from 14 CFR part 23, §§ 23.321 through 23.537, as applicable, corresponding to the system in the failed state with additional flight limitations or reconfiguration of the airplane. A factor of safety of 1.0 must be applied to determine ultimate loads.
(D) In addition to the requirements in 14 CFR part 23, §§ 23.571 through 23.574, comply with the following:
If any system failure would have a significant effect on the fatigue or damage evaluations required in §§ 23.571 through 23.574, then these effects must be taken into account. If an independent system functional test is required by SC 23.301(b), the effect on fatigue and damage evaluations resulting from the selected inspection interval must be taken into account.
(E) In addition to the requirements in 14 CFR part 23, § 23.629 Flutter, comply with the following:
(a) With the load alleviation system fully operative, compliance to 14 CFR part 23, § 23.629 must be shown. Compliance with § 23.629(f) must include the ATLAS control system and control surface.
(b) At the time of occurrence of load alleviation system failure and immediately after the failure, compliance with 14 CFR part 23, § 23.629(a) and (e) must be shown up to VD/MD without consideration of additional operating limitations or reconfiguration of the airplane.
(c) For airplanes equipped with “before the next flight” failure annunciation systems and the load alleviation system in the failed state, compliance to 14 CFR part 23, § 23.629 Flutter, paragraphs (a) and (e), must be shown up to VD/MD without consideration of additional operating limitations or reconfiguration of the airplane.
(d) For airplanes equipped with “immediate” failure annunciation systems and the load alleviation system in the failed state, compliance to 14 CFR part 23, § 23.629 Flutter, paragraphs (a) and (e), must be shown with consideration of additional operating limitations or reconfiguration of the airplane at speeds up to VD = 1.4 × maximum speed limitation selected by the applicant.
(A) In place of 14 CFR part 23, § 23.672 Stability augmentation and automatic and power-operated systems requirement, comply with the following:
(B) In place of 14 CFR part 23, § 23.677 Trim systems requirement, comply with the following:
(a) Proper precautions must be taken to prevent inadvertent, improper, or abrupt Tamarack Active Control Surface (TACS) operation.
(b) The load alleviation system must be designed so that, when any one connecting or transmitting element in the primary flight control system fails, adequate longitudinal control for safe flight and landing is available.
(C) In place of 14 CFR part 23, § 23.683 Operation tests requirement, comply with the following:
(D) In place of 14 CFR part 23, § 23.685 Control system details requirement, comply with the following:
(E) In place of 14 CFR part 23, § 23.697 Wing flap controls requirement, comply with the following:
(F) In place of 14 CFR part 23, § 23.701 Flap interconnection requirement, comply with the following:
Issued in Kansas City, Missouri, on July 13, 2013.
[FR Doc. 2012-17864 Filed 7-20-12; 8:45 am]