Development and Design Philosophy
David Thatcher developed the CX7 as the fourth aircraft in his experimental LSA series, following the successful single-seat CX4 (introduced around 2005) and tandem two-seat CX5 (circa 2013). The CX7 designation skipped the CX6 number entirely, proceeding directly to address homebuilders' requests for side-by-side seating configuration. Thatcher's design objectives centered on creating an LSA-compliant aircraft that would provide the social benefits of side-by-side seating while maintaining the affordability and simplicity that characterized his earlier designs.
The prototype development phase began around 2017-2018, with Thatcher hand-building the wings, tail, and fuselage sections before selling the project to pilot Glen Bradley for completion and testing. This approach reflected the company's plans-built philosophy, where individual components are scratch-built by homebuilders rather than supplied as prefabricated kits.
Flight Testing and Technical Refinements
Glen Bradley conducted the CX7's maiden flight sometime before 2020, immediately discovering an unexpected nose-up flight tendency caused by aerodynamic lift generated by the fuselage itself. This characteristic, while similar to lift-producing fuselage designs found in Beechcraft and Cessna aircraft, required trim adjustments that Thatcher subsequently incorporated into the revised plans. The prototype completed its mandatory 40-hour test flight period by approximately 2020-2021, clearing the way for plans distribution to the homebuilding community.
The aircraft demonstrated extremely slow landing speeds, necessitating a free-swiveling nose gear design steered exclusively through differential braking rather than traditional rudder pedal steering. This configuration, while unconventional, proved effective for the CX7's intended low-speed operating envelope and simplified the landing gear construction requirements for builders.
Powerplant and Systems
The CX7 prototype utilizes a Revmaster 2300 engine, a Volkswagen-based horizontally opposed four-cylinder powerplant that continues Thatcher's commitment to affordable, automotive-derived propulsion. The Revmaster installation features proprietary heavy-duty internal components and incorporates dual ignition systems with eight individual coils providing single-plug redundancy for each cylinder. This configuration allows continued flight operation even with complete ignition system failures.
Dual fuel pump systems provide additional redundancy, combining a mechanical primary pump with an electric backup unit. These reliability enhancements reflect Thatcher's emphasis on safe recreational flying, particularly important given the aircraft's intended operation by amateur-built aircraft owners who may lack extensive maintenance support networks.
Production and Builder Community
Unlike traditional aircraft manufacturers, Thatcher Aircraft operates exclusively through plans sales rather than kit or completed aircraft production. No serial production of the CX7 has occurred, with construction limited to individual homebuilders working from detailed plans. The exact number of CX7 projects initiated remains undocumented, though the prototype appeared to be the sole flying example as of 2020.
This limited construction contrasts sharply with Thatcher's earlier designs, particularly the CX4, which had attracted over 585 builders across 20 countries by April 2018. The CX4 fleet had accumulated 3,316.6 flight hours across 60 airworthy examples by that date, demonstrating the viability of Thatcher's design philosophy and construction methods.
The Manufacturer's Evolution
Thatcher Aircraft, Inc. has maintained continuous operations since the mid-2000s, building a reputation within the experimental aircraft community for designs that prioritize affordability over performance. The company's growth paralleled the CX4's success, with first flights like N27CX occurring in November 2009 and steady expansion throughout the following decade.
David Thatcher's design approach emphasizes practical homebuilding considerations, including readily available Volkswagen engines, simplified construction techniques, and comprehensive documentation. The CX5 tandem design attracted over 110 builders, with estimated construction times ranging from 2,500 to 2,750 hours, providing realistic expectations for prospective CX7 builders.
Current Status and Legacy
The CX7 remains in limited production through plans sales, with Thatcher Aircraft continuing to refine the design based on prototype experience and builder feedback. The aircraft represents the most ambitious project in Thatcher's lineup, offering cabin width comparable to certified aircraft while maintaining experimental amateur-built affordability.
As the newest member of a successful aircraft family, the CX7's ultimate impact depends on homebuilder adoption rates and the completion of additional examples. The design's emphasis on redundant systems and gentle flight characteristics positions it well within the light sport aircraft market, particularly for builders seeking side-by-side seating without the complexity and expense of certified aircraft alternatives.