U .S. Department of Transportation Federal Aviation Administration Advisory Circular Subject: Powered-Lift Operations Date: 10/7/24 AC No: 194-1 Initiated by: AFS-800 Change:
This advisory circular (AC) describes how powered-lift will comply with specific regulations in Title 14 of the Code of Federal Regulations (14 CFR) parts 43, 91, 91 subpart K (part 91K), 97, 135, and 136. This AC does not provide compliance options for every regulation addressed in 14 CFR Part 194, Special Federal Aviation Regulation No. 120—Powered-Lift: Pilot Certification and Training; Operations Requirements, as several regulations do not require additional information. Instead, this AC provides clarification for specified regulations within Special Federal Aviation Regulation (SFAR) 120, Powered-Lift: Pilot Certification and Training;
Operations Requirements, to ensure powered-lift operate safely. This AC can be used to help in understanding some of the part 194 regulations and will remain in effect until permanent rules for powered-lift are developed.
The contents of this document do not have the force and effect of law and are not meant to bind t he public in any way, and the document is intended only to provide information to the public regarding existing requirements under the law or agency policies.
R obert M. Ruiz for Lawrence Fields Executive Director, Flight Standards Service
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CONTENTS Paragraph Page
Chapter 1. Introduction1-1
1.1 Purpose of This Advisory Circular (AC)1-1
1.2 Audience1-1
1.3 Where You Can Find This AC1-1
1.4 Background1-1
1.5 Powered-Lift Flight Modes1-2
1.6 AC Feedback Form1-2
Chapter 2. Part 43 Maintenance2-1
2.1 Applicability of Part 43 to Powered-Lift2-1
2.2 Maintenance and Inspection Provisions Applicable to Powered-Lift2-1
2.3 Powered-Lift Operations in Remote Areas Under Part 1352-1
2.4 Inspection of Critical Parts2-1
Chapter 3. Part 91 Operations3-1
3.1 Operations of Powered-Lift3-1
3.2 Part 91 Subpart A, General3-1
3.3 Part 91 Subpart B, Flight Rules3-1
3.4 Part 91 Subpart C, Equipment, Instrument, and Certificate Requirements,
and Part 91 Subpart D, Special Flight Operations3-9
3.5 Part 91 Subpart E, Maintenance, Preventive Maintenance, and Alterations3-11
3.6 Part 91 Subpart F, Large and Turbine-Powered Multiengine Airplanes
and Fractional Ownership Program Aircraft3-13
3.7 Part 91 Subpart G, Additional Equipment and Operating Requirements
for Large and Transport Category Aircraft3-18
3.8 Part 91 Subpart K, Fractional Ownership Operations3-19
3.9 Other Part 91 Considerations3-20
Chapter 4. Part 97 Operations fo r Powered-Lift4-1
4.1 Applicability of Copter Procedures Under Part 97 to Powered-Lift4-1
4.2 Part 97, Standard Instrument Procedures4-1
4.3 Instrument Approach Procedures (IAP)4-1
4.4 Powered-Lift Seeking IFR and Copter Procedure Approval4-1
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Chapter 5. Part 135 Operations5-1
5.1 Organization of Topics5-1
5.2 Applicability of SFAR 120 to Powered-Lift Part 135 Operations5-1
5.3 Section 135.93, Minimum Altitudes for Use of Autopilot5-2
5.4 Section 135.152, Flight Data Recorders (refer to § 194.306(p) through (r))5-2
5.5 Section 135.154, Terrain Awareness and Warning System, and § 135.605, Helicopter Terrain Awareness and Warning
System (HTAWS) (refer to § 194.306(s) and (ooo))5-3
5.6 Section 135.203, VFR: Minimum Altitudes5-4
5.7 Section 135.209, VFR: Fuel Supply5-5
5.8 Section 135.221, IFR: Alternate Airport Weather Minimums5-5
5.9 Section 135.223, IFR: Alternate Airport Requirements5-6
5.10 Section 135.227, Icing Conditions: Operating Limitations (refer to
§ 194.306(ww) and (xx))5-6
5.11 ACs Requiring Further Explanation for the Integration of Powered-Lift5-7
Table 5-1. Revised VFR Air Ambulance Minimums in Class G Airspace5-12
Chapter 6. Part 136 Commercial Air Tours and Nat ional Parks Air Tour Management6-1
6.1 Part 136 Applicability6-1
6.2 Part 136 Subpart A, National Air Tour Safety Standards6-1
6.3 Special Operating Rules for Air Tour Operators in the State of Hawaii6-3
Appendix A. List of Acronyms ................................................................................................... A -1 Appendix B. Related Reading Material .......................................................................................B- 1
1-1 CHAPTER 1. INTRODUCTION
1.1 Purpose of This Advisory Circular (AC).
1.1.1 Powered-Lift and Title 14 of the Code of Federal Regulations (14 CFR). This AC describes how powered-lift will comply with specific regulations in 14 CFR parts 43, 91, 91 subpart K (part 91K), 97, 135, and 136. This AC does not provide compliance options for every regulation addressed in 14 CFR part 194, as several do not require additional information. Instead, this AC provides clarification for specified regulations within Special Federal Aviation Regulation (SFAR) 120, Powered-Lift: Pilot Certification and Training; Operations Requirements, to ensure powered-lift operate safely. This AC can be used to help in understanding some of the part 194 regulations and will remain in effect until permanent rules for powered-lift are developed.
1.1.2 P owered -Lift and Applicable Aircraft Rules. Parts 43, 91, 91K, 97, 135, and 136 contain some provisions that are applicable to all aircraft and some provisions that specify applicability to a particular kind of aircraft (e.g., airplane or rotorcraft). Powered-lift are aircraft as defined in 14 CFR part 1, § 1.1 and, as explained in part 194, § 194.301, must comply with regulations that are applicable to aircraft. In addition, the SFAR requires powered-lift to comply with regulations that specify applicability to a particular kind of aircraft. This AC describes how powered-lift comply with specific airplane, rotorcraft, and helicopter rules contained in parts 43, 91, 91K, 97, 135, and 136. Because this AC discusses the applicability of existing rules to powered-lift operations, it contains numerous references to other ACs, orders, and guidance material. These documents can be found on the Dynamic Regulatory System (DRS) located at https://drs.faa.gov.
1.1.3 Effects of Guidance. This AC is intended to support powered-lift operations during the term of the SFAR. It is not mandatory and does not constitute a regulation. The contents of this document do not have the force and effect of law and are not meant to bind the public in any way, and the document is intended only to provide information to the public regarding existing requirements under the law or agency policies.
1.1.4 R egulatory Requirements. The content of this AC does not change or create any additional regulatory requirements, nor does it authorize changes in, or permit deviations from, existing regulatory requirements.
1.2 Audience. The primary audience for this AC includes pilots and operators intending to operate powered-lift in accordance with parts 43, 91, 91K, 97, 135, and/or 136.
1.3 Where You Can Find This AC. You can find this AC on the Federal Aviation Administration’s (FAA) website at https://www.faa.gov/regulations_policies/advisory_cir culars and DRS at https://drs.faa.gov.
1.4 Background.
1.4.1 Concurrently with publication of this AC, the FAA has published a final rule establishing the requirements for pilot certification and operation of powered-lift through the publication of the SFAR. Powered-lift are defined in part 1 as heavier-than-air aircraft
1-2 capable of vertical takeoff, vertical landing, and low-speed flight that depend principally on engine-driven lift devices or engine thrust for lift during these flight regimes and on nonrotating airfoil(s) for lift during horizontal flight. Powered-lift may be capable of vertical takeoff and landing (VTOL) operations or conventional takeoffs and landings, while being able to fly like an airplane during cruise flight. The powered-lift SFAR will establish a regulatory structure that leverages the existing rules, removes operational barriers, and mitigates safety risks for powered-lift.
1.4.2 The FAA conducted a review of ACs that may be relevant to powered-lift. These are listed in Appendix B, Related Reading Material.
1.5 Powered-Lift Flight Modes. Powered-lift are hybrid aircraft capable of operating in a manner similar to airplanes (wing-borne flight mode) and rotorcraft (vertical-lift flight mode). The FAA refers to these modes as wing-borne flight mode and vertical-lift flight mode.
1.5.1 V ertical -Lift Flight Mode. Vertical-lift flight mode means a mode of flight where a powered-lift:
• I s in a configuration that allows vertical takeoff, vertical landing, and low- speed flight; and
• Depends principally on engine-driven lift devices or engine thrust for lift.
1.5.2 Wi ng -Borne Flight Mode. Wing-borne flight mode means a mode of flight where a powered-lift is not operating in the vertical-lift flight mode as defined and depends exclusively or partially on nonrotating airfoil(s) for lift during takeoff, landing, or horizontal flight.
1.5.3 Autorotation. Autorotation means a rotorcraft or powered-lif t flight condition in which the lifting rotor is driven entirely by action of the air when the rotorcraft or powered-lift is in motion.
1.6 A C Feedback Form. For your convenience, the AC Feedback Form is the last page of this AC. Note any deficiencies found, clarifications needed, or suggested improvements regarding the contents of this AC on the Feedback Form.
2-1 CHAPTER 2. PART 43 MAINTENANCE
2.1 Applicability of Part 43 to Powered-Lift. Powered-lift meet the definition of an aircraft as defined in § 1.1 and must comply with all part 43 maintenance requirements that are applicable to aircraft in accordance with § 43.1(a)(1), unless otherwise specified in the Special Federal Aviation Regulation (SFAR) 120, Powered-Lift: Pilot Certification and Training; Operations Requirements.
2.2 Maintenance and Inspection Provisions Applicable to Powered-Lift. The following maintenance provisions under part 43 that pertain to rotorcraft also apply to powered-lift:
1. Section 43.3(h) applies to certificate holders (CH) operating powered-lift under part 135 in a remote area; and
2. In lieu of complying with § 43.15(b), each person performing an inspection required by part 91 on a powered-lift shall inspect critical parts in accordance with the maintenance manual or instructions for continued airworthiness (ICA), or as otherwise approved by the Administrator. “Critical part” under the SFAR has the same meaning as provided in 14 CFR part 27, § 27.602 and part 29, § 29.602.
2.3 Powered-Lift Operations in Remote Areas Under Part 135. Under part 135, § 135.429(d), the Administrator may approve a CH to authorize a pilot in remote areas when no other qualified person is available to have a required inspection performed on a rotorcraft by that pilot that meets the criteria addressed in § 135.429(d). Powered-lift CHs will be allowed under the SFAR to use the same process to receive this approval from the FAA currently in place for rotorcraft and will contact their responsible Certificate Management Team (CMT). Section 194.402(a) requires CHs operating powered-lift in remote areas under part 135 to comply with the preventive maintenance protocols prescribed in § 43.3(h). Section 194.306(lll) requires pilots performing the specific preventive maintenance functions to be properly trained and qualified in accordance with § 135.429(d).
2.4 Inspection of Critical Parts. Section 194.402(b) applies the definition of a “critical part” in §§ 27.602 and 29.602 to powered-lift subject to the inspection outlined in § 43.15(b), as specified in the aircraft manufacturer’s maintenance manual. The intent for critical part inspections will be the same as currently written in § 43.15 for rotorcraft, but may have different nomenclature for powered-lift critical parts as specified in the maintenance manual or ICAs. In lieu of complying with § 43.15(b), each person performing an inspection required by part 91 on a powered-lift shall inspect critical parts in accordance with the maintenance manual or ICA, or as otherwise approved by the Administrator.
3-1 CHAPTER 3. PART 91 OPERATIONS
3.1 Operations of Powered-Lift. Persons operating powered-lift must continue to comply with rules applicable to all aircraft in part 91. In § 194.302, Table 1 to § 194.302 outlines the airplane, helicopter, and rotorcraft provisions that are applicable to powered-lift.
Moreover, any provisions in part 91 that are specific to a category of aircraft such as airplane or helicopter, and that are not outlined in Table 1 to § 194.302, do not apply to powered-lift.
3.2 Part 91 Subpart A, General. Powered-lift must comply with the provisions in part 91 subpart A that are applicable to aircraft. Paragraphs 3.2.1 and 3.2.2 below detail how the regulations in part 91 subpart A that contain airplane- or helicopter-specific provisions apply to powered-lift. The FAA also amended a small number of regulations to accommodate powered-lift, discussed herein.
3.2.1 Section 91.1, Applicability. The provisions in part 91 subpart A are applicable to all aircraft operating in the National Airspace System (NAS) unless specifically excepted, such as for aircraft governed by 14 CFR part 103 or 107. The FAA changed the term “airplane” to “aircraft” in § 91.1(d) to include powered-lift, because the FAA intends for powered-lift to comply with the provisions in part 91 subpart A.
3.2.2 Section 91.9, Civil Aircraft Flight Manual, Marking, and Placard Requirements.
Section 91.9(a) and (b) contains references to “Airplane or Rotorcraft Flight Manual.”
The FAA intends for powered-lift operators to comply with the manual requirements and any additional requirements in § 91.9. The FAA will evaluate the aircraft flight manual during type certification for acceptability. Thus, § 194.302(a) requires powered-lift to comply with § 91.9. Although the Powered-Lift’s Aircraft Flight Manual (PLAFM) will not refer to an airplane or rotorcraft as specified in § 91.9, the FAA is applying the requirements set forth in § 91.9 to powered-lift with an aircraft flight manual.
3.3 Part 91 Subpart B, Flight Rules. Powered-lift must comply with the provisions in part 91 subpart B that are applicable to aircraft. Paragraphs 3.3.1 through 3.3.14 below detail how the regulations in part 91 subpart B that contain airplane- or helicopter-specific provisions apply to powered-lift.
3.3.1 Section 91.103, Preflight Action (refer to § 194.302(b)). Section 91.103 contains the requirement for a pilot in command (PIC) to be familiar with all available information concerning a flight, including takeoff and landing distance data as specified in the approved Airplane or Rotorcraft Flight Manual. Due to the hybrid capabilities of powered-lift, a PIC must be familiar with takeoff and landing distances for all applicable flight modes. Section 194.302(b) requires powered-lift with an aircraft flight manual approved through the certification process to comply with the provisions in § 91.103.
3.3.2 Section 91.107, Use of Safety Belts, Shoulder Harnesses, and Child Restraint Systems (refer to § 194.302(c)). Section 194.302(c) makes § 91.107(a)(3) applicable to all powered-lift. In § 91.107(a)(3) for seaplane and float-equipped rotorcraft operations during movement on the surface, persons pushing off a seaplane or float-equipped
3-2 rotorcraft from the dock or persons mooring a seaplane or rotorcraft at a dock are excepted from the seating and safety belt requirements. The exceptions also apply to powered-lift in § 194.302(c). For further information about how to comply with § 194.302(c), powered-lift operators should apply the information contained in the current edition of AC 91-69, Seaplane Safety for 14 CFR Part 91 Operators.
3.3.3 Section 91.109, Flight Instruction; Simulated Instrument Flight and Certain Flight Tests.
Section 91.109 requires the use of fully functional dual controls for aircraft used in flight instruction with exceptions for free manned balloon and instrument instruction in airplanes with a single functioning throwover control wheel. However, the powered-lift final rule adopted provisions to facilitate pilot certification in powered-lift with a single functioning flight control and single pilot station.
Note: Further discussion of powered-lift and fully functioning dual controls for f light instruction is contained in AC 194-2, Pilot Training and Certification for Powered-Lift Operations.
3.3.4 Section 91.113, Right-of-Way R ules: Except Water Operations.
3.3.4.1 Section 91.113 requires all powered-lift to comply with § 91.113(d)(2) and (d)(3). Under the rule in § 91.113, when aircraft of the same category are converging at approximately the same altitude (except head-on, or nearly so), the aircraft to the other’s right has the right-of-way. When the aircraft are of different categories, § 91.113(d)(1) through (d)(3) establishes a hierarchy giving priority to balloons, then gliders, followed by airships, and then to airplanes and rotorcraft. An aircraft that is towing or refueling other aircraft has right-of-way over all other engine-driven aircraft. Under the revised § 91.113, powered-lift, airplanes, and rotorcraft are grouped in the same right-of-way category. Thus, if a powered-lift is converging with an airplane, the aircraft to the right has the right-of-way.
3.3.4.2 To comply with this rule, powered-lift should refer to the current editions of AC 90-48, Pilots’ Role in Collision Avoidance, and AC 90-66, Non-Towered Airport Flight Operations. When referring to AC 90-66, powered-lift operators should note that the term “powered-lift” should be considered equivalent to the terms “airplane” or “rotorcraft.” For example: A glider has the right-of-way over an airship, powered parachute, weight-shift-control aircraft, airplane, rotorcraft, or powered-lift. Also, an airship has the right-of-way over a powered parachute, weight-shift-control aircraft, airplane, rotorcraft, or powered-lift.
3.3.5 Section 91.119, Minimum Safe Altitudes: General. Section 91.119 prescribes the minimum safe altitude (MSA) for aircraft operations. Section 91.119(d) contains an exception for helicopters, powered parachutes, and weight-shift-control aircraft, allowing them to operate below the minimum altitudes prescribed in § 91.119(b) and (c) when certain conditions are met. Powered-lift operating in the vertical-lift flight mode that have demonstrated the capability to autorotate or conduct an approved equivalent maneuver
3-3 are allowed the same MSAs as those afforded to helicopters in § 91.119(d), as outlined in § 194.302(d). With regard to powered-lift utilizing helicopter routes, the FAA notes that some helicopter routes may be lower than a minimum altitude published in the aircraft flight manual for a given powered-lift configuration (e.g., an altitude which enables a transition from wing-borne flight mode to vertical-lift flight mode at an altitude sufficient to conduct a safe autorotation, or an approved equivalent maneuver, to a landing).
Regardless of any clearance or helicopter route prescribed altitude, no powered-lift may operate lower than any limitation specified in the aircraft flight manual or any other limitation. The Administrator reiterates that a clearance by air traffic does not grant exemption from any rule. Section 91.9 requires compliance with all aircraft flight manual limitations at all times.
3.3.6 Section 91.126, Operating On or In the Vicinity of an Airport in Class G Airspace (re fer to § 194.302(e) and (f)).
3.3.6.1 When entering the traffic pattern to land, powered-lift may transition between wing-borne flight mode and vertical-lift flight mode. Wing-borne flight mode (forward flight) is similar to an airplane, and vertical-lift flight mode (vertical flight) is similar to a helicopter.
3.3.6.2 If the powered-lift intends to land in wing-borne flight mode, § 194.302(e) requires the pilot to comply with § 91.126(b)(1) and make all turns of the powered-lift to the left, unless the airport displays approved light signals or visual markings indicating that turns should be made to the right, in which case the pilot must make all turns to the right. If the powered-lift is operating in vertical-lift flight mode, § 194.302(f) requires the pilot to comply with § 91.126(b)(2) and avoid the flow of fixed-wing aircraft.
3.3.6.3 To comply with this rule, powered-lift operators should refer to AC 90-66.
Powered-lift pilots must consider their mode of flight in accordance with § 194.302(e) and (f). For example, AC 90-66, paragraph 12.1.1 states “[i]n the case of a helicopter approaching to land other than on the runway in use, the pilot should avoid the flow of fixed-wing aircraft and land on a marked helipad or suitable clear area.” Therefore, powered-lift operating in vertical-lift flight mode would comply with the helicopter provision, avoid the flow of fixed-wing aircraft, and land on a marked helipad or suitable clear area.
3.3.7 Section 91.129, Operations in Class D Airspace (refer to § 194.302(g) through (j)). The provisions of § 91.129(a) through (d), (g)(1), and (i) refer to aircraft and are applicable to powered-lift.
3.3.7.1 S ection 91.129(e) and (g) Minimum Altitudes When Operating To an Airport in Class D Airspace. Section 91.129(e) and (g) specifies minimum altitudes for landing, approaches and departures at an airport in Class D Airspace. Section 91.129(h) prescribes noise abatement requirements for large or turbine-powered airplanes. The provisions of these rules are necessary for
3-4 noise abatement and to ensure adequate terrain clearance for large or turbine-powered airplanes. Section 194.302(g) requires large or turbine-powered powered-lift to comply with the provisions in § 91.129(e)(1),
(e)(2), (g)(2), and (h). Furthermore, operators must note these provisions apply to all large or turbine-powered powered-lift regardless of the flight mode they may be operating in.
3.3.7.2 Section 91.129(e)(3) Approaching to Land on a Runway Served by a Visual Approach Slope Indicator (VASI) (refer to § 194.302(h)).
3.3.7.2.1 Section 194.302(h) requires a powered-lift pilot intending to land in wing-borne flight mode and approaching a runway served by a VASI to comply with § 91.129(e)(3). The pilot must operate the powered-lift at an altitude at or above the glidepath until a lower altitude is necessary for a safe landing. The requirement for powered-lift to remain at or above the glidepath ensures adequate obstacle clearance is maintained during the approach.
3.3.7.2.2 Powered-lift pilots intending to land in vertical-lift flight mode are anticipated to be flying more slowly than powered-lift pilots landing in wing-borne flight mode. Thus, the slower speed and the ability to maneuver like a helicopter make it unnecessary to comply with § 194.302(g)(1).
3.3.7.3 Section 91.129(f)(1) Class D Airspace Landing Approach Procedures (refer to § 194.302(i)).
3.3.7.3.1 Section 194.302(i) requires powered-lift pilots intending to land in wing-borne flight mode to comply with the airplane rule in § 91.129(f)(1). The pilot must circle the airport to the left unless the powered-lift is conducting a circling approach under part 97 or if the pilot is otherwise directed by air traffic control (ATC).
3.3.7.3.2 Sec tion 194.302(j) requires powered-lift pilots intending to land in vertical-lift flight mode to comply with the helicopter rule in § 91.129(f)(2) and avoid the flow of fixed-wing traffic unless the powered-lift is conducting a circling approach under part 97 or if the pilot is otherwise directed by ATC.
Note: In § 194.302(i)(2) and (j)(2), the requirements of § 91.129(f) do not apply to powered-lift conducting a circling approach under part 97 because a circling approach may have specific procedures established, or turns may be requested by ATC to ensure safety in the traffic pattern.
3.3.7.4 Section 91.129(h) Runway Usage Requirements (refer to § 194.302(g)).
Section 194.302(g) requires large or turbine-powered powered-lift to comply with § 91.129(h). Under the Special Federal Aviation Regulation (SFAR) 120, where a formal runway use program has been established by the FAA, each pilot of a large or turbine-powered powered-lift must use the noise abatement runway assigned by ATC. However, the PIC remains the final authority
3-5 concerning the safe operation of the aircraft, as prescribed in § 91.3(a), and may request that ATC assign a different runway in the interest of safety.
3.3.8 Section 91.131, Operations in Class B Airspace (refer to § 194.302(k)). The current provisions of § 91.131(a)(2) are applicable to large turbine-engine-powered airplanes.
However, the FAA anticipates that certain powerplants, such as electric motors, may have equal or better performance in comparison to internal combustion engines;
therefore, operators of powered-lift must note that under the SFAR, all large powered-lift, regardless of powerplant type, must comply with § 194.302(k). This requires a person operating a powered-lift to or from a primary airport for which Class B Airspace is designated to operate at or above the designated floors of the Class B Airspace area while within the lateral limits of that area. This is to ensure that large powered-lift remain deconflicted from smaller aircraft that may be operating under Class B Airspace and not receiving air traffic services.
3.3.9 Section 91.151(a) and (b), Fuel Requirements for Flight in VFR Conditions (refer to § 194.302(l)).
3.3.9.1 Except in accordance with § 194.302(l), all powered-lift must comply with the airplane fuel requirements prescribed in § 91.151(a). In accordance with § 194.302(l), powered-lift with the performance capability (as outlined in the aircraft flight manual) to conduct a landing in the vertical-lift flight mode along the entire route of flight may use the visual flight rules (VFR) fuel requirements outlined in § 91.151(b). However, if the powered-lift cannot be assured of a safe landing in vertical-lift flight mode along the entire route of flight, then compliance with § 91.151(a) would be required.
3.3.9.2 Indications that a powered-lift may not be assured of a safe landing in vertical-lift flight mode along the entire route of flight may include a limitation or requirement in the aircraft flight manual that would preclude such a landing. Likewise, the powered-lift may not be capable of transitioning from wing-borne to vertical-lift flight mode quickly enough to comply. This provision will not prevent a powered-lift from operating in wing-borne flight mode. Rather, it will require the powered-lift to have the performance capability (as detailed in the aircraft flight manual) to conduct a landing in vertical-lift flight mode along the entire route of flight in order to take advantage of the rotorcraft VFR fuel requirements.
Note: The term “fuel” includes any form of energy used by an engine or powerplant installation, such as provided by carbon-based fuels or electrical potential. The term “fuel systems” includes a means of storage for the electrical energy provided (e.g., batteries that provide energy to an electric motor) or devices that generate energy for propulsion (e.g., solar panels or fuel cells).
3.3.10 Section 91.155, Basic VFR Weather Minimums (refer to § 194.302(m), (n), and (o)).
Section 91.155 permits helicopters to operate under lower visibility and cloud clearance
3-6 minimums than airplanes in Class G Airspace. The FAA recognizes that helicopters operate at lower speeds and are capable of greater maneuverability than other aircraft.
This allows pilots to see and avoid other air traffic or obstructions in time to prevent a collision. Powered-lift may have equivalent maneuvering capabilities to helicopters when operating in vertical-lift flight mode and therefore may comply with the helicopter provisions in certain circumstances. To comply with these provisions, powered-lift must be operated at a speed that allows the pilot enough time to see and avoid any other air traffic, or any obstructions in time to avoid a collision. A powered-lift that cannot be operated at a speed that allows the pilot enough time to see and avoid any other air traffic or any obstructions to avoid a collision, regardless of the mode of flight, must comply with the airplane visibility minimums prescribed in § 91.155(a) and (b)(2).
3.3.11 Section 91.157, Special VFR We ather Minimums (refer to § 194.302(p)). Section 91.157 permits helicopters to operate under lower visibility and cloud clearance minimums than airplanes. For the same reasons stated in paragraph 3.3.10 above, powered-lif t may comply with the helicopter exceptions of § 91.157(b)(3), (b)(4), and (c), provided powered-lift are operated at a speed that allows the pilot enough time to see and avoid any other air traffic or any obstructions in time to avoid a collision. As such, § 194.302(p) stipulates that the helicopter exceptions outlined in § 91.157(b)(3), (b)(4), and (c) apply to powered-lift operating in vertical-lift flight mode when those aircraft are operated at a speed that allows the pilot to see any other traffic or obstructions in time to avoid a collision.
3.3.12 S ection 91.167, Fuel R eq uirements for Flight in IFR Conditions (refer to § 194.302(q)).
3.3.12.1 Section 91.167(a)(1) through (3) specifies no person may operate a civil aircraft in instrument flight rules (IFR) conditions unless it carries enough fuel (considering weather reports and forecasts and weather conditions) to:
1. Complete the flight to the first airport of intended landing;
2. If necessary, and except as provided in § 91.167(b), to fly from that airport to the alternate airport; and
3. To fly after that for 45 minutes at normal cruising speed or, for helicopters, fly after that for 30 minutes at normal cruising speed.
3.3.12.2 Because a powered-lift can operate similarly to a helicopter, powered-lift are required to only carry the fuel reserves of a helicopter in certain circumstances. As such, powered-lift authorized to conduct Copter Procedures and that have the performance capability, as provided in the aircraft flight manual, for the entire flight to conduct a landing in the vertical-lift flight mode may comply with the IFR fuel requirements established for helicopters.
3.3.12.3 Furthermore, during aircraft certification, the FAA will assess the aircraft’s stability, system, and equipage for IFR operations. A powered-lift that does not possess these characteristics may still be certificated for IFR but will be prohibited from performing Copter Procedures and have a limitation in the