2024-14489. Draft Policy Statement on Special Class Rotorcraft

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Department of Transportation

Federal Aviation Administration

1. 14 CFR Part 21
2. [Docket No. FAA-2024-1794]

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of availability; request for comments.

SUMMARY:

The FAA invites public comment on the agency's draft policy statement PS-AIR-21.17-02, “Special Class Rotorcraft.” This proposed policy would identify certain rotorcraft as special class.

DATES:

Comments must be received on or before September 9, 2024.

ADDRESSES:

Send comments identified with “PS-AIR-21.17-02” and docket number FAA-2024-1794 using any of the following methods:

• Federal eRulemaking Portal: Go to www.regulations.gov and follow the online instructions for sending your comments electronically.
• Mail: 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.
• Hand Delivery or Courier: 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.
• Fax: Fax comments to Docket Operations at 202-493-2251.

Privacy: The FAA will post all comments received without change to www.regulations.gov, including any personal information the commenter provides. DOT's complete Privacy Act Statement can be found in the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at DocketsInfo.dot.gov.

FOR FURTHER INFORMATION CONTACT:

James Blyn, Product Policy Management: Airplanes, GA, Emerging Aircraft, and Rotorcraft AIR-62B, Policy and Standards Division, Aircraft Certification Service, Federal Aviation Administration, 10101 Hillwood Pkwy., Fort Worth, Texas 76177; telephone [phone]; email [e-mail].

SUPPLEMENTARY INFORMATION:

Background

Advancements in technology have resulted in the development of electrically powered rotorcraft with more than two main rotor systems. Although these aircraft are rotorcraft as defined in 14 CFR part 1, the FAA has found that they are not typical of the rotorcraft designs utilizing main and auxiliary rotors envisaged by the rotorcraft airworthiness standards in 14 CFR parts 27 and 29.

Rotorcraft type-certificated in the normal and transport categories under parts 27 and 29, respectively, have primarily been helicopters that use a single main rotor and an anti-torque rotor or two main rotors to provide lift and thrust for horizontal flight. Helicopters create lift by changing the pitch of the main rotor blades and move into horizontal flight by varying the pitch of the main rotor blades throughout their rotation.

Over the past few years, the FAA has been working with potential applicants on certification projects for normal category rotorcraft designs that create lift and thrust by using multiple (three or more) rotor systems. Instead of varying the pitch of the rotor blade throughout its rotation, these aircraft create directional control for horizontal movement by varying the power at each rotor. These aircraft also rely on electric or hybrid-electric propulsion and not (or not only) a traditional internal combustion engine. Additionally, they employ advanced flight control system designs, such as fly-by-wire, that are highly integrated with the electric propulsion system. These designs provide extensive flight envelop protection and introduce high levels of automation.

During these projects, the FAA has found that existing type certification criteria do not accommodate or apply to these rotorcraft. For example, only 60 percent of the requirements in part 27 may be appropriate for these designs. Some of the remaining requirements are not applicable and would need exemptions from the regulatory requirements. For other requirements, due to the novel and unusual design, applicants would need special conditions to modify the existing standards. Furthermore, additional airworthiness criteria, for which there are no standards in part 27, would require special conditions to provide an appropriate safety standard to address the novel and unusual design features.

The FAA amended 14 CFR part 21 at amendment 21-60 to add procedural requirements for the issuance of type certificates for special classes of aircraft in § 21.17(b). In the Final Rule, the FAA explained that it intended the special class category to include, in part, those aircraft that would not be eligible for certification under existing standards due to their unique, novel, or unusual design features. The FAA further stated that the “decision to type certificate an aircraft in either the special class aircraft category or under part 23 of the [CFR] is entirely dependent upon the aircraft's unique, novel, and/or unusual design features.” (52 FR 8040, March 13, 1987).

The rotorcraft described in the paragraphs above have those unique, novel, or unusual design features the special class category was designed to accommodate. Type certificating these rotorcraft under part 27 or 29 with exemptions and special conditions would be a lengthy administrative process. The resulting certification basis will likely contain a portion of the existing airworthiness standards combined with a significant number of special conditions containing unique airworthiness criteria. Moreover, the special class process provides the public greater visibility of the complete certification basis. The level of safety provided by the certification basis would be the same under either process.

Accordingly, the FAA has determined that special class rotorcraft as defined in this policy are sufficiently different from the normal and transport category rotorcraft envisaged by parts 27 and 29, respectively, to be considered a “special class” of rotorcraft under § 21.17(b). This finding is consistent with the definition of “class” in part 1 as used with respect to the certification of aircraft. The FAA has concluded that designating these rotorcraft as a special class under § 21.17(b) would provide a more practical means of type certification and is in the public interest. Additionally, an applicant for a special class rotorcraft may use propellers in place of rotors for the rotorcraft's lift and directional control.

Comments Invited

The FAA invites the public to submit comments on the draft policy statement, as specified in the ADDRESSES section. Commenters should include the subject line “PS-AIR-21.17-02” and the docket number FAA-2024-1794 on all comments submitted to the FAA. The most helpful comments will reference a specific portion of the draft document, explain the reasons for any recommended change, and include supporting data. The FAA will consider all comments received on or before the closing date before issuing the final policy statement. The FAA will also consider comments filed late if it is possible to do so without incurring expense or delay.

You may examine the draft advisory circular on the agency's public website and in the docket as follows:

• Athttp://www.regulations.gov in Docket Number FAA-2024-1794.
• Athttp://www.faa.gov/​aircraft/​draft_​docs/​.

Issued in Kansas City, Missouri, on June 26, 2024.

Patrick Mullen,

Manager, Technical Policy Branch, Policy and Standards Division, Aircraft Certification Service.