Dave's aircraft works PF-5

Model Airplane News, Sep 2000 by Garwood, Dave

Hoot 'n' holler flying with an easy-build, micro electric

Electric flight is making a walloping resurgence with the introduction of great-flying little models, small, light powerplants, microservos, diminutive receivers and speed controls. Best of all, the new generation of electric slow flyers can be flown in truly tight spaces, including indoors, in a parking lot, schoolyard, or even in your driveway. One of these new electric park flyers, the Dave's Aircraft Works* (DAW) PF-5, is a remarkable design that incorporates loads of high-tech materials, makes good use of the latest in miniaturized radio and servo gear and delivers hoot 'n' holler flight time in a compact yet robust package. In addition, the solid flight performance and predictable flight characteristics of the PF-5 make it a candidate for training new RC pilots.

State-of-the-art onboard radio gear is crucial to successful micro flight, and with the guidance of Dave Sanders of DAW, I installed two Hitec* HS-SO Feather servos and a Todd's Models* DC-5 geared motor and prop with a SOmAh, 8-cell battery pack. Most amazing of all is the Sky Hooks & Rigging* RX-72 hybrid receiver that incorporates a motor speed control. This 3.5-gram device is a marvel of electronics engineering and production.

WHAT'S IN THE BOX?

The kit includes a fully assembled, gracefully curved EPP-foam wing with carbon spar already installed. The wing assembly is completely free of hot-wire hairs, the leading edge is fully shaped, and the wing tapers to a 116-inch-thick trailing edge.

The fuselage is a laminated balsa and carbon-cloth pod with a carbon-fiber rod fuselage boom. Lightening holes are predrilled, and the boom is mounted at the factory. The 1/i6-inch balsa tail parts are precut and sanded; rudder and elevafor hinges are installed at the factory.

The small parts bag includes 0.020-inch music-wire pushrods, Teflon tubing for the pushrod guides, heat-shrink tubing to hold the pushrod guides in place, more heat-shrink tubing for wiring insulation and plastic sheet stock for the control horns.

The 11-page, illustrated instruction manual discusses motor selection and suitable sub-microservos, receivers and speed controls. The manual thoroughly covers construction and setup for flight.

ON THE WORKBENCH

I began construction by studying the instructions and figuring out the wiring harness; by the time I got the trimming and soldering done, about two hours had passed.

The first building session included fitting the tail parts, test balancing, mounting the servos with Goop adhesive and spraying the wingtips with red Krylon. I was finished in an hour and a half.

DIVE'S AIRCRAFT WORKS PF-5

In the second building session, I set up the control linkages, checked the balance again and decided to move the servos farther aft (to the position recommended by the designer!), installed the RX-72 receiver/speed control with Goop, installed the molded landing-gear struts with epoxy and sprayed the orange stripe on the wing. All this took two and a half hours.

During the third and final building session, I used CA to mount the landing-gear axles and the wing, mounted the motor and propeller (both press-fits) and then did a final balance check and sprayed the yellow onto the wing. I finished in an hour.

Note that no wing finishing and little tail-parts finishing is needed; these are done at the factory. Construction time, including motor, servo and control-linkage installations, totaled 6-1/2 hours and would have taken half an hour less if I hadn't had to move the servos. This plane could go from box to flightline in a day.

My completed PF-S weighed 4.2 ounces-near the midpoint of the recommended weight range, thanks in large part to the light onboard components used throughout.

FLIGHT REPORT

I first flew my PF-5 indoors in the Houston Field House hockey rink at Rensselaer Polytechnic Institute (RPI) in Troy, NY. My wife, Paula, drives a Zamboni there and was able to arrange some "ice time" for flight testing.

First was a high-speed taxi test to check control response and radio range and then a short 50-foot hop at 2 feet of altitude to check rudder and elevator response. Both were fine: snappy but not oversensitive.

Next was an ROG takeoff and climb to 15 feet, flying a racetrack pattern over the hockey rink. The plane climbs rapidly and positively and turns quickly and smoothly. When power to the motor is pulled back, it transitions well to gliding.

I flew four flights in the arena, each lasting from 3 to 6 minutes. It was a simple matter to keep the plane inside the confines of the Plexiglas barriers around the rink because it handles so well and, because it has plenty of power, the PF-5 easily climbed up near the 40-foot ceiling. The carbon-fiber landing gear and wheels worked well for both takeoffs and landings.

The next flying session was outdoors, over a snow-covered field in a municipal park. This time I launched by hand, and each flight started just fine. In the wide-open spaces, the low flight speed of the plane is more apparent; I'd estimate 7 to 8mph at 112 throttle. This time, the PF-5 climbed easily and was able to loop with a shallow preparatory dive.