By Tim Fiedler, EAA Lifetime 256056
This piece originally ran in the September 2024 issue of EAA Sport Aviation magazine.
This was started in 1992 by Jim LePard, an A&P/IA mechanic who resides near Spokane, Washington, who substantially completed the airframe over the ensuing years. Jim’s workmanship is outstanding; all who have seen it have commented on the quality of his construction.
Jim eventually decided to sell the unfinished airframe to Ron Shannon, who lived at the Rake’s Glen residential airpark near Sequim, Washington, in 2006. Ron was an attorney, musician, political activist, record and concert promoter, hiker, sailor, pilot, builder and repairer of houses, boats, and airplanes, computer network designer, father, and husband. Ron elected to finish the airplane and certify it in the light-sport category at 1,320 pounds gross weight, originally installing a 120-hp six-cylinder Jabiru engine and a dual-screen Advanced Flight Systems 3500 avionics suite.
Ron received his airworthiness certificate on July 13, 2010, four years after picking up the airplane from Jim. Ron had the aircraft painted by Michael Payne, who also resides at Rake’s Glen Airport. Even after getting N254MR in the air, Ron was constantly “tweaking” the aircraft toward perfection.
Ron put approximately 350 hours on the airframe once it received its airworthiness certificate, including two trips to Oshkosh. Ron chased fuel tank leaks for most of the time he owned the aircraft but loved everything else about it and was an avid contributor to the MurphyBuilders.net user community. Ron’s last flight in N254MR was in November 2015. Sadly, Ron never flew the airplane again, and he died on April 27, 2020, four-and-a-half years after a diagnosis of brain cancer.
During 2018 and 2019, I was looking to build a STOL aircraft. While considering various build options, Michael Payne alerted me to the availability of N254MR. After seeing the craftsmanship on the aircraft and taking a short demo flight, I was impressed and purchased the aircraft from Ron’s widow, Miggles, in the summer of 2020.
I flew the aircraft in the original configuration for about six months and decided not to keep the Jabiru engine and light-sport aircraft certification. Today, many, if not most, of the hundreds of airworthy Rebels fly with Lycoming O-320 or O-360 variants. Of note, a suitable engine mount and cowl for these engines was available to purchase from Murphy Aircraft. Ultimately, I decided to go with an experimental XO-340 (basically a stroked O-320) Continental Titan rated at 176 hp (low-compression pistons and no fuel injection to preserve the ability to use automotive fuel if needed). The Titan was developed by ECI as a high-horsepower, low-weight engine in conjunction with CubCrafters for the Carbon Cub. Subsequently, Continental purchased ECI and has continued to make these Titan “Lycoming clone” engines for CubCrafters and experimental applications.
I placed an order for the Continental XO-340 Titan, equipped with dual Light Speed Plasma III electronic ignitions. Simultaneously, I ordered a custom Catto three-bladed composite propeller, and the diameter and pitch were based on Craig Catto’s knowledge and experience. I also ordered the engine mount and fiberglass “speed” cowl from Murphy Aircraft.
My goal in using the XO-340 Titan and Catto prop combination was to keep the completed aircraft as light as possible, maximize available power, and minimize the weight on the nose. The cost of all this fun was not my top consideration.
I took the aircraft to Mike Robertson and Bend Builder’s Assist in Bend, Oregon. Initially, while we waited for the Titan engine to arrive, we installed a used experimental Lycoming O-320 I had purchased for the purpose of making sure any potential cooling and firewall forward details could be sorted out before the installation of the Titan engine. This temporary engine allowed us to get the aircraft airborne and test the new engine mount, cowl, ignition, controls, installation, and accessories.
While the original engine swap from the Jabiru to the interim O-320 engine was being performed, Rob Hickman’s team from Advanced Flight Systems upgraded the panel via its AdvancedPanel offering to its current configuration, including a 10-inch AF-5600 display (upgraded recently with the AF-6600 microprocessor), Advanced engine management system, Advanced remote audio panel, and G3X Touch Garmin backup EFIS. This installation is built around the Advanced Control Module, the central hub for all wiring connections. This module also provides electronic circuit breakers for the entire airplane, except for the electronic ignition modules and the alternator. This IFR-certified aircraft features a Garmin 650Xi, ADS-B In and Out capability, and a fully coupled Advanced three-axis autopilot. Safety features include GPS position input to the ACK emergency locator transmitter, a panel-mounted CO2 detector, and an oximeter.
I flew the aircraft with the O-320 for about 10 hours and proved that the installation details and cowl modifications resulted in excellent CHTs and appropriate oil temperatures. At this point, the aircraft returned to Bend Builder’s Assist to swap the O-320 for the XO-340 Titan. Initial test flights with the XO-340 showed no anomalies during or after a short engine break-in period. Paperwork was submitted, and the gross weight was upped to the standard Rebel 1,650 pounds. The metamorphosis was complete.
Recently, Tim Boughner from Tim’s Aircraft Repair in Port Orchard, Washington, installed an upgraded 3200 tail wheel and a new, stiffer tail wheel spring. Future upgrades include adding TK 1 Racing’s STOL landing gear, researching rudder trim from Aerosport Products, and installing potentially bigger tires to replace the 22-inch tires on the aircraft.
N254MR isn’t particularly light, coming in at 1,075 pounds’ empty weight, with a 575-pound useful load. The wing tanks hold 22 gallons each, with a total of 42 gallons usable. The aircraft cruises (using 75 percent power) at 109 knots, stalls at about 31 knots, and takes off in about 180 feet at full gross, making it a super STOL and backcountry aircraft. The roomy cabin, side-by-side seating, great visibility, and ample baggage space make the Murphy Rebel a favorite for everyone who has flown or traveled in the airplane.