Development and Design Philosophy
Darryl Murphy announced the Radical project in January 2016 with ambitious performance targets that would surpass his company's successful Rebel design. The new aircraft incorporated engineering lessons learned from four Murphy models—the Rebel, Elite, Maverick, and Super Rebel—into a single airframe optimized for serious backcountry flying. Murphy's design objectives called for higher gross weight capability, increased wing area, and compatibility with engines up to 220 horsepower.
The prototype achieved first flight in 2016 and made its public debut at EAA AirVenture Oshkosh in July 2016, where it attracted attention not only for its performance potential but also for practical features like under-wing bicycle racks for ground transportation at remote airstrips.
Construction and Technical Innovation
The Radical employs riveted aluminum construction throughout, featuring a monocoque fuselage and built-up strut-braced wings with stamped ribs and aluminum skins. Murphy's engineering team prioritized ease of assembly, using pulled rivets for most construction joints while reserving solid rivets only for critical wing spar attachments. Control surfaces utilize fabric covering to reduce weight, while primary flight controls operate through traditional pushrod systems for ailerons and elevators.
With an empty weight of 1,150 pounds and maximum gross weight of 2,100 pounds, the Radical can carry substantial loads while maintaining STOL performance. The aircraft's 44-gallon fuel capacity provides extended range for backcountry expeditions.
Powerplant Options
Murphy designed the Radical around two Lycoming engine options: the standard 180-horsepower O-360 and the optional 220-horsepower IO-390. Both are four-cylinder, air-cooled, horizontally-opposed engines manufactured by Lycoming Engines, a division of Textron Aviation. The O-360, which entered production in 1955, has proven itself reliable through more than 40,000 units built and continues in production today.
The prototype configuration initially used an IO-370 Titan engine, while customer-built examples have featured fixed-pitch Catto propellers paired with modern avionics including Garmin G3X Touch panels.
Production Challenges and Revival
Despite the successful 2016 prototype debut, full-scale kit production faced significant delays due to company ownership changes and extensive kit redesigns. Murphy Aircraft implemented computer-aided design and manufacturing processes to improve documentation quality and provide pre-drilled components for faster assembly.
Kit production finally commenced in summer 2023 under new ownership led by CEO Jensen Li, with sales management handled by Doug Thorpe and Steve Drinkwater. The company estimates 1,000 hours for kit completion, significantly reduced from typical amateur-built aircraft construction times.
The Murphy Aircraft Legacy
Founded by Darryl Murphy in 1985 in Chilliwack, British Columbia, Murphy Aircraft has shipped approximately 3,000 kits over nearly four decades, with roughly half of those aircraft now flying. The company's product line has included 850 Rebel kits, 350 Super Rebel kits, 800 Renegade kits, and 100 Maverick kits.
The Renegade's early success illustrates Murphy's persistence in the kit aircraft market. After selling only one kit in the first six months of 1986, the company built momentum through EAA Oshkosh displays and positive aviation press coverage, ultimately delivering 129 Renegade kits by 1989.
Following the 2022 ownership change, Murphy Aircraft temporarily halted production to update its entire product line, resuming operations in 2023 with three primary models: the Moose, Radical, and Rebel.
Current Status and Operations
As of 2023, only two Radical aircraft have achieved flight status: the factory prototype and a customer-built example completed by Marco Probst. Probst's aircraft has demonstrated the Radical's intended mission capability through operations from challenging locations including gravel bars along the Squamish River, showcasing the aircraft's backcountry credentials.
Four additional kits remain under construction by customers, with five total kits sold since production began. The limited production reflects both the aircraft's recent market introduction and the extended development timeline.
Market Position
The Radical targets serious backcountry pilots seeking enhanced performance over traditional two-seat STOL aircraft. Its four-seat capacity and substantial payload capability position it for family backcountry flying and extended wilderness expeditions where previous Murphy designs might prove limiting.
Manufacturing continues at Murphy Aircraft's Chilliwack facility, where the company maintains its focus on robust, easy-to-build metal construction that has characterized Murphy designs for nearly four decades.