Special Conditions: Skyryse, Robinson Helicopter Company Model R66 Helicopter; Interaction of Systems and Structures

DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 27</CFR> <DEPDOC>[Docket No. FAA-2024-0875; Notice No. 27-24-01-SC]</DEPDOC> <SUBJECT>Special Conditions: Skyryse, Robinson Helicopter Company Model R66 Helicopter; Interaction of Systems and Structures</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), DOT. <HD SOURCE="HED">ACTION:</HD> Notice of proposed special conditions. <SUM> <HD SOURCE="HED">SUMMARY:</HD> This action proposes special conditions for the Robinson Helicopter Company (Robinson) Model R66 helicopter. This helicopter, as modified by Skyryse, will have a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for normal category helicopters. This design feature is a novel control input and fly-by-wire (FBW) system. 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. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Send comments on or before October 15, 2024. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Send comments identified by Docket No. FAA-2024-0875 using any of the following methods: <E T="03">Federal eRegulations Portal:</E> Go to <E T="03">www.regulations.gov</E> and follow the online instructions for sending your comments electronically. <E T="03">Mail:</E> 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. <E T="03">Hand Delivery or Courier:</E> Take comments to 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. <E T="03">Fax:</E> Fax comments to Docket Operations at 202-493-2251. <E T="03">Docket:</E> Background documents or comments received may be read at <E T="03">www.regulations.gov</E> at any time. Follow the online instructions for accessing the docket or go to 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. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Daniel Moore, Airframe Section, AIR-622, Technical Policy Branch, Policy and Standards Division, Aircraft Certification Service, Federal Aviation Administration, 901 Locust, Kansas City, MO 64106; telephone (303) 342-1066; email <E T="03">Daniel.E.Moore@faa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Comments Invited</HD> The FAA invites 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 proposed special conditions, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date for comments, and will consider comments filed late if it is possible to do so without incurring delay. The FAA may change these special conditions based on the comments received. <HD SOURCE="HD1">Privacy</HD> Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in title 14, Code of Federal Regulations (14 CFR) 11.35, the FAA will post all comments received without change to <E T="03">www.regulations.gov,</E> including any personal information you provide. The FAA will also post a report summarizing each substantive verbal contact received about these special conditions. <HD SOURCE="HD1">Confidential Business Information</HD> Confidential Business Information (CBI) is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to these special conditions contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to these special conditions, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and the indicated comments will not be placed in the public docket of these proposed special conditions. Send submissions containing CBI to the individual listed in the For Further Information Contact section above. Comments the FAA receives, which are not specifically designated as CBI, will be placed in the public docket for these proposed special conditions. <HD SOURCE="HD1">Background</HD> On April 10, 2023, Skyryse applied for a supplemental type certificate for removal of the mechanical control system and installation of a computer controlled flight control system in the Model R66 helicopter. The Robinson Model R66 helicopter, currently approved under Type Certificate No. R00015LA, is a single engine normal category rotorcraft. The maximum take-off weight is 2,700 pounds, with a maximum seating capacity of five passengers. <HD SOURCE="HD1">Type Certification Basis</HD> Under the provisions of 14 CFR 21.101, Skyryse must show that the Robinson Model R66 helicopter, as changed, continues to meet the applicable provisions of the regulations listed in Type Certificate No. R00015LA or the applicable regulations in effect on the date of application for the change, except for earlier amendments as agreed upon by the FAA. If the Administrator finds that the applicable airworthiness regulations do not contain adequate or appropriate safety standards for the Robinson Model R66 helicopter 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 applicant apply for a supplemental type certificate to modify any other model included on the same type certificate to incorporate the same novel or unusual design feature, these special conditions would also apply to the other model under § 21.101. In addition to the applicable airworthiness regulations and special conditions, the Robinson Model R66 helicopter 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 § 11.38, and they become part of the type certification basis under § 21.101. <HD SOURCE="HD1">Novel or Unusual Design Feature</HD> The Robinson Model R66 helicopter will incorporate the following novel or unusual design feature: Novel control input and FBW system. <HD SOURCE="HD1">Discussion</HD> Skyryse is proposing to install an FBW flight control system (FCS) intended to replace the current hydraulicly boosted mechanical primary FCS, on a Robinson Model R66 helicopter. FBW systems are new to part 27 rotorcraft and as such, the rotorcraft FCS will now contain control functions that affect the static strength of rotorcraft structure. These proposed special conditions would give the applicant an option to offset the structural factor of safety based on the probability of system failure. These proposed special conditions apply to systems that can induce loads on the airframe or change the response of the rotorcraft to maneuvers or to control inputs, as a result of failure. Some potential examples include part 27 rotorcraft equipped with FBW or fly-by-light FCSs, autopilots, stability augmentation systems, load alleviation systems, flutter control systems, fuel management systems, and other systems that either directly or as a result of failure or malfunction affect structural performance. The FAA has issued special conditions for the interaction of systems and structures to other aircraft in the past (parts 23, 25, and 29). Active flight control systems are capable of providing automatic responses to inputs from sources other than the pilots. These automatic systems may become inoperative or may operate in a degraded mode, which could impact the loads envelope and rotorcraft static strength. Therefore, it is necessary to determine the structural factors of safety and operating margins such that the joint probability of structural failures due to application of loads during system malfunctions is not greater than that found in rotorcraft equipped with earlier technology control systems. To achieve this objective, it is necessary to define the failure conditions with their associated frequency of occurrence in order to determine the structural factors of safety and operating margins that will ensure an acceptable level of safety. The 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. <HD SOURCE="HD1">Applicability</HD> As discussed above, these proposed special conditions are applicable to the model for which they are issued. Should the applicant apply for a supplemental type certificate to modify any other model included on the same type certificate to incorporate the same novel or unusual design feature, these special conditions would apply to the other model as well. <HD SOURCE="HD1">Conclusion</HD> This action affects only a certain novel ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 23k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━