Airworthiness Criteria: Special Class Airworthiness Criteria for the Wing Aviation LLC; Hummingbird Unmanned Aircraft

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 21</CFR> <DEPDOC>[Docket No. FAA-2022-1763]</DEPDOC> <SUBJECT>Airworthiness Criteria: Special Class Airworthiness Criteria for the Wing Aviation LLC; Hummingbird Unmanned Aircraft</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), Department of Transportation (DOT). <HD SOURCE="HED">ACTION:</HD> Issuance of final airworthiness criteria. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The FAA announces the special class airworthiness criteria for the Wing Aviation LLC (Wing) Hummingbird unmanned aircraft (UA). This document sets forth the airworthiness criteria that the FAA finds to be appropriate and applicable for the UA design. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> These airworthiness criteria are effective February 12, 2024. </EFFDATE> <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Mack A. Martinez, Product Policy Management—Emerging Aircraft Section, AIR-62B, Technical Policy Branch, Policy and Standards Division, Aircraft Certification Service, Federal Aviation Administration, 2300 East Devon Avenue, Room 335/339, Des Plaines, IL 60018, telephone (847) 294-7481. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Background</HD> Wing Aviation LLC (Wing) applied to the FAA on September 19, 2018, for a special class type certificate (TC) under 14 CFR 21.17(b) for the Model Hummingbird UA. The Model Hummingbird consists of a fixed-wing airplane UA and its associated elements (AE) including communication links and components that control the UA. The Model Hummingbird UA has a maximum gross takeoff weight of approximately 15 pounds. It is approximately 3.4 feet in width, 4.2 feet in length, and 9.4 inches in height. The Model Hummingbird UA is battery powered using electric motors for vertical takeoff, landing, and forward flight. The unmanned aircraft system (UAS) operations would rely on high levels of automation and may include multiple UA operated by a single pilot, up to a ratio of 20 UA to 1 pilot. Wing intends for the Model Hummingbird to be used to deliver packages. The proposed concept of operations (CONOPS) for the Model Hummingbird includes a maximum operating altitude of 400 feet above ground level, a maximum cruise speed of 68 knots, operations beyond visual line of sight (BVLOS), and operations over people (OOP). Wing has not requested approval for flight into known icing for the Model Hummingbird UA. Under § 21.17(c), an application for type certification is effective for 3 years. Section 21.17(d) provides that where a TC has not been issued within that 3-year time limit, the applicant may file for an extension and update the designated applicable regulations in the type certification basis. The effective date of the applicable airworthiness requirements for the updated type certification basis must not be earlier than 3 years before the date of issue of the TC. Since the project was not certificated within 3 years after the application date above, the FAA approved the applicant's request to extend the application for type certification. As a result, the date of the updated type certification basis is September 26, 2022. The FAA issued a notice of proposed airworthiness criteria for the Wing Model Hummingbird UA, which published in the <E T="04">Federal Register</E> on February 8, 2023 (88 FR 8333). <HD SOURCE="HD1">Discussion of Comments</HD> The FAA received responses from 5 commenters. The comments came from industry organizations such as the Air Line Pilots Association (ALPA), the Association for Uncrewed Vehicle Systems International (AUVSI), the Small Unmanned Aerial Vehicles (UAV) Coalition, the Commercial Drone Alliance, and Wing Aviation LLC. <HD SOURCE="HD1">Specific Issues Raised Within the Scope of the Notice</HD> <E T="03">D&R.100 UA Signal Monitoring and Transmission:</E> The FAA proposed criteria on the minimum types of information the FAA finds are necessary for the UA to transmit to the AE for continued safe flight and operation. <E T="03">Comment Summary:</E> ALPA is concerned with the possibility of cyber security breaches that could allow unauthorized individuals to take control of a UA, potentially leading to safety issues. As such, it is important to address these concerns and establish an acceptable envelope of tolerance for UA operation that ensures the security of the signal monitoring and transmission systems. <E T="03">FAA Response:</E> These comments are outside the scope for D&R.100. The comments by ALPA on cyber security, D&R.115, are addressed in the following paragraph. <E T="03">D&R.115 Cyber Security:</E> The FAA proposed a requirement to address the risks to the UA associated with intentional unauthorized electronic interactions that may result in an adverse effect on the security or airworthiness of the UA. <E T="03">Comment Summary:</E> ALPA is concerned with the safety and security of the Command and Control (C2) link and potential unauthorized intrusions that could result in the loss of full control over the aircraft. ALPA recommends that every UA model requesting operations in the National Airspace System (NAS) undergo testing and validation during the aircraft certification process to ensure the security of the C2 link is impenetrable and cannot be hacked. ALPA states that reports have shown that the loss of the C2 link and the inability to regain it has led to an uncontained flyaway. ALPA focuses on the most critical aspects of safe UA operations and recommends specific requirements to ensure the safe discontinuation of a flight after a failure of a critical part or system and/or unauthorized intrusion of the C2 link. Other recommendations include the ability of the pilot to re-route the UA safely and dynamically, the ability for the UA control station to allow the pilot to intervene in the management of the flight, an established parameter requirement for geo-fencing specifications, and a requirement for the UA to possess the capability to detect and avoid other aircraft and hazards that are human made/manufactured and natural. <E T="03">FAA Response:</E> The proposed recommendations are too specific for this general airworthiness criteria language; the language already covers the general issues that ALPA's specific recommendations seek to address. D&R.115 states that the UA equipment, systems, and networks must be assessed to identify and mitigate protections as necessary. The level of detail regarding the assessment of failures and the required protection level of equipment, systems, and networks will be addressed in the means of compliance (MOC) to these airworthiness criteria. The C2 link is addressed in the airworthiness criteria under D&R.120 Contingency Planning for a C2 lost link or degradation of a C2 link, as well as performance requirements. The C2 link is considered part of the UA and will be assessed for cyber security under D&R.115 as part of equipment and systems. <E T="03">D&R.120 Contingency Planning:</E> The FAA proposed a requirement to address the risks associated with loss of communication C2 link between the pilot and the UA. The proposed criteria requires that the UA be designed to automatically execute a predetermined action and include the predetermined action in the UA Flight Manual. The UA Flight Manual must also include the minimum performance requirements for the C2 data link defining when the C2 link is degraded to a level where active control is no longer ensured. Takeoff when the C2 link is degraded below minimum performance requirements must be prevented by design or by an operating limitation to be included in the UA Flight Manual. <E T="03">Comment Summary:</E> ALPA expressed several areas of concern related to UA contingency planning that the FAA should consider during the aircraft certification process. These concerns include addressing the risks associated with loss of communication, defining detailed preprogrammed algorithmic deliverables and corrective actions for each situation, and ensuring that the UA can automatically execute a safe predetermined flight, loiter landing, or termination in the event of any critical parts or systems failures. ALPA has several recommendations including to have the applicant “Develop a detailed narrative that outlines every possible action that the UA will execute when guidance/intrusion challenges arise after the first preterminal action is initiated with the flight of the aircraft until all maneuvering actions have been exhausted and no further options exist.” ALPA also recommends a test and validation of the effectiveness of the pre-determined executable actions to ensure proper design and definition of UA as intended. <E T="03">FAA Response:</E> The FAA shares ALPA's concerns and has determined that the current airworthiness criteria appropriately address these concerns. The airworthiness criteria within D&R.120(a) propose the automatic and immediate execution of a safe predetermined action, in the event of a loss of communications, be part of the UA design. Furthermore, D&R.120(b) proposes that established predetermined actions are included in the UA Flight Manual, thus ensuring the applicant outlines these predetermined maneuvering actions within their contingency planning. Test and validation methods, of the effectiveness of such pre-determined actions as part of mitigation planning by which the UA will meet these criteria are addressed by D&R.310(a) and will be outlined in the MOC. <E T="03">D&R.125 Lightning:</E> The FAA proposed criteria to address the risks that would result from a lightning strike, accounting for the size and physical limitations of a UAS that could preclude traditional lightning protection features. The FAA further proposed that without lightning protection f ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 56k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━