Radio Control: Slope Soaring
David Sanders 34455 Camino El Molino, Capistrano Beach, CA 92624
AMA Slope Duration Record
There aren't a great deal of competitive opportunities for the typical slope flier; you've basically got Racing, Combat, or Scale. There is one other little-mentioned score card, though: the Academy of Model Aeronautics (AMA) record book.
On May 10, two intrepid slope-flying colleagues, Rex Coffman and Dean Thomas, both from Eureka, California, set out to take a stab at the AMA Class A Slope Duration record. Armed with good batteries and some time to kill, each made 11-hour-plus flights. Rex took top honors with a flight of 11 hours and 43 minutes, besting Dean's time by 22 minutes. For any of you who have tried duration flying, you know that this is a long, long time to be standing on the hill pushing the sticks!
Rex achieved the record flight with a C.R. Aircraft Models Climax. (See? How many times have I told you to leave home without a hand-launch airplane?) The Climax is widely recognized as one of the all-time great, high-utility hand-launched gliders out there.
Dean's equally impressive effort was accomplished using his own-design Panther. Congratulations to Rex and Dean for a true ironman effort!
Production Slope Racers — the Viper
Quite a few people have the need for speed, but getting the best airframe can be an arduous task; the best ones are often built by cottage industries with only so much ability to meet the public's hunger for fast, state-of-the-art models.
Stephen (Steve) Situm in San Rafael, California, notified me that he was putting into production a new Unlimited-class racer designed by F3B World Champion Daryl Perkins, in coordination with noted aero engineer Gavin Botha. The Viper has been carefully optimized for the slope racing task. Let's take a look at some of the details.
Following the trend of today's hottest new F3B and Thermal Duration models, the Viper is fully molded. For those not familiar with this construction, it means that all parts are hollow and constructed of thin fiberglass shells to create the airframe's form. Advantages are fidelity to shape and profile, as well as light weight and strength. Parts are painted in the molds and factory-assembled, which eliminates almost all finishing work for the user.
The Viper's geometry and airfoil were carefully worked out and tested by a world-class team of designers, which takes things to the highest levels. Highlights include:
- V-tail design with a 112.2-inch span
- Triple-tapered wing planform
- Aspect ratio: 14.3:1
- Wing area: 900 square inches
- Dry weight: 73–77 ounces
- Three-piece wing: center section bolted to the fuselage; outer panels fixed with 1/2 x 3/8 carbon joiners for a strong monolithic structure at the high bending-stress joint
The airfoil is the RG-15. The Viper can be ballasted to the full 5 kg Fédération Aéronautique Internationale (FAI) weight limit—a nontrivial design goal given the challenge of fitting 100 ounces of lead into a narrow glass fuselage.
The wings are prewired for servos, control surfaces are cut and hinged, all pushrod housings are installed, and specially manufactured control horns by Paul Trist are included.
The Viper is notable as a top-level, competitive racing model that a regular slope flier can actually obtain; Steve anticipates a waiting time of about four weeks. The Viper costs $950 in kit form. Steve can install and set up radio equipment for another $150 to deliver a Ready-to-Fly model.
Contact:
- Steve Situm, 4 Friar Tuck Lane, San Rafael, CA 94901
- Tel.: (415) 456-2996
- Web: http://members.aol.com/rcsoaring
McLeans Models and Northeast Sailplane Products
Another company you might have seen mentioned is McLeans Models. Brian McLean manufactures a 60-inch-class Vindicator racer, a recognized top-level machine, and an Apex Unlimited-class model. Brian has moved; contact information:
- McLeans Models, 4198 Bowyer Blvd., Redding, CA 96002
- Tel.: 530-222-4127
- E-mail: mcmodels@aol.com
Sal DeFrancesco of Northeast Sailplane Products (NSP) markets Brian's aircraft and several other very competitive models. Contact NSP:
- Sal DeFrancesco, Northeast Sailplane Products, 16 Kirby Lane, Williston, VT 05495
- Tel/Fax: 802-658-9482
- Web: http://www.nesail.com
Power Slope Soaring — the U-2
This month I thought I'd show a little Power Slope Soaring (PSS) action; several people have been talking about the Lockheed U-2 subject. PSS has ideal geometry—long, thin wings and a sailplane-ish fuselage—the original U-2 makes a natural PSS project.
One U-2, built by Bill Young in Minnesota, is painted with automotive bumper paint, which the model's designer, Gus Morfis, says gives a good approximation in color and gloss to the scale, all-black finish on the U-2 and other U.S. spy planes, such as the B-57D or SR-71. Bill's model has:
- Span: 65 inches
- Wing area: 556 square inches
- Aspect ratio: 10.2:1
- Control: aileron/elevator
Nice work.
Gus Morfis Designs
Gus's designs utilize all-balsa construction with conventional wood-sheeted, foam-core wings, making them familiar and inexpensive for those of us who still build models out of wood. They can finish out quite nicely.
Many of Gus's plan sets cost less than twenty dollars, and any one would make a good winter project. There are several to choose from, in military and civilian categories, and some are quite unusual.
Contact:
- Gus Morfis, 4709 Green Meadows Ave., Torrance, CA 90505-5507
- Tel.: (310) 378-5679
Conclusion
So, there's this month's juicy stuff. Enjoy the fall winds before you're all buried in snow or drowning in rain for the winter!
Transcribed from original scans by AI. Minor OCR errors may remain.
