New Roadable Aircraft
Folding wing design features sliding motorcycle engine
By Fareed Guyot, Manager – Electronic Publications, EAA 388642
N10ZX roadable aircraft in “ground” configuration
Cockpit features individual controls for both ground and flight operations.
10ZX departs on its first flight April 11, 2011. The rails on which the trike engine slides forward and aft during transition are visible on the bottom of the fuselage.
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May 26, 2011 — When landscape architect Rick Johnson, EAA 343934, of Palm City, Florida, was looking for a deeper aircraft building challenge, he thought, "Why not build a roadable aircraft?" The result is the merger of an Avid Magnum with a Suzuki motorcycle that is street legal, yet flies through the air. This "airplane-first" powered-wheel design is similar to the Plane Driven's PD-1, a modified Glastar Sportsman we saw at Oshkosh last year. But Rick's design came well before that one; he spent the last eight years and 10,000 hours building it. The design is even more compact featuring a transition from ground power to flight that employs an unlikely concept.
“I’m creative,” Johnson said. “I’m always building something.” During the project Rick got key assistance from EAA Chapter 203 (Palm City) Technical Counselor Bill Perry.
Starting with the Avid Magnum, which is a taildragger, he modified the design to adapt to the roadable aspects of the aircraft. The frame was beefed up; 13-inch radial tires with disc brakes were added to the landing gear as well as rack-and-pinion steering as the vehicle is steered by the main gear on the ground.
The “trike engine,” as Johnson calls it in this application, is a 400cc, four-stroke, water-cooled, 32-hp Suzuki that was also modified to allow for reverse drive. It attaches to the fuselage just in front of the tail wheel. Riding along on the ground, you only hear the purr of the motorcycle engine, which can propel the vehicle up to 60 mph; Johnson claims the roadable aircraft has good handling at highway speeds. N10ZX also has a valid Florida license plate that reads “FLYN CAR.”
Transitioning to/from flight takes about 20 minutes. The wings are swept forward from their folded-back position, struts are attached, and the extra lights used for ground operations such as emergency flashers, turn signals, and head and brake lights are stowed. But having the trike engine so far back presents an obvious center of gravity problem. Johnson solved this by installing rails on the bottom of the fuselage. The engine then slides forward to a location between the main gear, where it is rotated 90 degrees and tucked nicely out of the way.
In the cabin, the customization is even more apparent. To accommodate the aircraft’s dual role the flight control stick is floor-mounted in front of the left seat and a steering wheel is floor-mounted in front of the right seat. Johnson also has a modern panel including a Grand Rapids Technologies Sport SX flight display and a multi-functional display that features some Garmin software to give him turn-by-turn instructions on the ground.
The two-place Avid with roadable attachments features a gross weight of 1,850 pounds carried by a 2.5-liter, four-stroke Subaru engine with an RFI belt-reduction drive and a Prince Aircraft propeller. Once in the air the aircraft should cruise at 95 knots, although Rick has not tested the aircraft in the air with the motorcycle attached. The Avid minus the trike engine did make its first flight on April 11.
The flight test with the motorcycle attached should come once some final modifications are completed, but the aircraft is already turning some heads. Last weekend, Johnson drove N10ZX to nearby North Palm Beach Country airport, where EAA Chapter 203 was holding an International Learn to Fly Day event. Along the 35-mile route to the event he got lots of curious looks, and he got plenty of questions and interest at the airport, where the Avid was on display. Johnson gave a few chapter members a ride in the aircraft and the chapter as a whole flew 50 Young Eagles.
Asked what he is going to do with his design, Rick said he had no commercial plans for the aircraft and that he did this mostly for his own entertainment. He noted that one cannot just get into the vehicle and drive off; any operator of N10ZX will need to have at least a private pilot certificate with conventional gear endorsement and a driver’s license with motorcycle endorsement.
We begged Rick to bring the N10ZX to AirVenture this summer and join the other roadable aircraft expected to attend, but that will likely have to wait for another year due to work commitments at that time.