Overview
The Modernization of Special Airworthiness Certification (MOSAIC) final rule builds on the 2004 light-sport rule and responds to evolving needs in recreational aviation, flight training, and certain aerial work. It aims to expand access to safe, modern, and affordable aircraft while maintaining a high level of safety.
- Updates airworthiness certification for light-sport category aircraft and related aircraft.
- Expands sport pilot privileges and training paths.
- Updates maintenance and repairman rules for light-sport and related experimental aircraft.
- Revises several Part 91 operating rules, including Class G and right-of-way rules.
Publication & Effective Dates
The MOSAIC final rule was published on July 24, 2025, with two main effective dates.
| Date | What Changes |
|---|---|
| October 22, 2025 (90 days after publication) |
|
| July 24, 2026 (365 days after publication) |
|
Light-Sport Category Aircraft Certification
MOSAIC amends 14 CFR part 21 and adds part 22 to use more performance-based rules for light-sport category aircraft. This supports innovation across a wider range of aircraft types.
Key Changes for Light-Sport Category Aircraft
- Performance-based standards instead of strict prescriptive limits.
- Manufacturers may design and certify a broader array of aircraft, including rotorcraft and powered-lift.
- Previous weight limits that blocked safety-enhancing designs and equipment are removed.
- Higher allowable stall speeds:
- Airplanes: up to 61 knots VS0
- Gliders: up to 45 knots VS0
- Supports faster, higher-performing aircraft suitable for personal travel.
- Enables more capable aircraft for flight training, with greater passenger, fuel, and cargo capacity.
- Allows new propulsion systems (including electric), any number of engines, new propeller types, and retractable gear.
- Creates a path for aircraft with simplified flight controls that can reduce flight hour requirements for certain pilot certifications.
Sport Pilot Certification
MOSAIC changes the performance and design limits on aircraft that sport pilots may operate, and adds a new “simplified flight controls” concept.
Expanded Sport Pilot Aircraft Privileges
- Removes explicit aircraft weight and airspeed limits.
- Allows use of any powerplant type except turbo-jet engines.
- Sets a new maximum stalling speed (VS1, flaps up) of 59 knots CAS.
- Allows operation of aircraft with retractable landing gear.
- Allows operation of airplanes with manual controllable-pitch propellers.
- Permits operation of 4-seat airplanes, while retaining the 2-occupant limit for sport pilots.
- Adds sport pilot night operation privileges (subject to other applicable requirements).
Note: The aircraft must have met the applicable requirements at the time of original certification. This means that stall reducing devices such as vortex generators and STOL kits added after original certification cannot be used when determining the 59 CAS flaps up stall speed.
Simplified Flight Controls
- New aircraft designation for designs that can automatically control flight path and prevent loss of control under likely conditions, regardless of pilot input. (§ 22.180)
- Any pilot certificate level may operate these aircraft with the proper make/model endorsement.
- Endorsement is available under § 61.31(l); instructors under parts 61 subpart H and K must hold the appropriate make/model endorsement to instruct in these aircraft. (§ 61.195(m), § 61.415(m))
New Sport Pilot Practical Tests
The FAA added new testing standards in § 61.14 for:
- Sport Pilot, Rotorcraft Category, Helicopter — Simplified Flight Controls Privileges ACS.
- Flight Instructor with a Sport Pilot Rating for Rotorcraft Category, Helicopter — Simplified Flight Controls Privileges ACS.
Sport pilots or instructors adding airplane or helicopter simplified-controls privileges to an existing certificate must take a practical test with a pilot examiner.
Maintenance & Light-Sport Repairman Updates
Repairman Certificate Eligibility & Privileges
- U.S. citizenship is no longer required.
- Privileges are now defined by aircraft category (Airplane, Glider, Rotorcraft, Powered-lift, Weight-Shift-Control, Powered Parachute, Lighter-Than-Air).
- Limitations are based on class where applicable (e.g., Rotorcraft-gyroplane, Rotorcraft-helicopter, LTA-airship, LTA-balloon).
- Privileges extend to certain experimental aircraft:
- Amateur-built (E-AB) – § 21.191(g)
- Kit-built light sport – § 21.191(k)
- Former light-sport category – § 21.191(l)
- Inspection-rated repairmen may only work on aircraft they own; N-numbers and serial numbers are no longer printed on the certificate.
Maintenance of Light-Sport Category Aircraft
- Airworthiness Directives (ADs) are mandatory; manufacturer Safety Directives (SDs) are recommended.
- Major repairs and major alterations must be authorized by the manufacturer or another person acceptable to the FAA.
- Minor repairs and minor alterations do not require prior authorization.
- Major work must follow maintenance and inspection procedures developed by the manufacturer or a person acceptable to the FAA.
Light-Sport Repairman Training Courses
- Course providers must:
- Administer a course test with a minimum passing score of 70% (per § 65.17).
- Issue a certificate of completion.
- Provide appropriate facilities, equipment, materials, and qualified instructors.
- Course acceptance is by aircraft category (and class where applicable).
- Maintenance courses must include relevant content from the Mechanic Airman Certification Standards; FAA acceptance is now content-based rather than hour-based.
- Existing FAA-accepted course content remains appropriate under MOSAIC.
Notes:
• E-AB aircraft with operating limitations issued before Oct. 22, 2025 must obtain revised operating limitations if a light-sport repairman is to perform the annual condition inspection.
• E-AB repairman certificates under § 65.104 are unchanged by MOSAIC.
Operations & Part 91 Changes
MOSAIC also updates several operational rules, including new allowances for certain experimental and restricted category aircraft and clearer rules for towing, right-of-way, and Class G airspace.
Experimental Aircraft Operations
- Allows operating limitations for certain experimental aircraft to fly over densely populated areas and in congested airways for all phases of flight.
- Permits former military aircraft with experimental airworthiness certificates to operate for certain new purposes (e.g., repositioning for public aircraft use).
New Flight Operations
- Restricted category aircraft: may be relocated to exhibitions, trade shows, and similar events.
- Light-sport category aircraft:
- May conduct certain aerial work operations.
- Includes additional requirements for glider and unpowered ultralight towing under § 91.309 and § 21.190 when done for compensation or hire.
- Sets maximum occupants: up to 4 in airplanes and 2 in other aircraft types (sport pilots are still limited to 2 occupants).
- Experimental space support vehicles:
- Codifies space support flight operations for certain experimental aircraft.
- Allows carriage of persons or property for compensation or hire without an air carrier certificate or exemption (subject to conditions in the rule).
New Operating Rules
- Towing: Clarifies how tow hitches may be attached to eligible light-sport category aircraft.
- Right-of-way: Updates and clarifies rules to include more aircraft, including those using non-traditional propulsion systems.
- Class G airspace: Includes more aircraft types and refines separation and avoidance expectations based on operational needs, aircraft configuration, and speed.
MOSAIC Resources & Further Reading
Use this section to link pilots, instructors, and operators to official documents and training materials related to MOSAIC.
Official Rules & Guidance
- MOSAIC Final Rule in the Federal Register
- FAA MOSAIC Fact Sheet
- 14 CFR Part 61 Subpart J
- Updated Sport Pilot Practical Test Standards
- AC 61-146
- AC 61-65K