Author: W. Byers
Edition: Model Aviation - 1996/03
Page Numbers: 111, 112, 113
,
,

RADIO CONTROL: SLOPE SOARING

Wil Byers 3540 Eastlake Dr., West Richland, WA 99352 wilbyers@aol.com

INTERNET CONNECTIONS

The Internet is an electronic communications network that links millions of computers and gives users access to a vast web of information with the click of a mouse. For model aviation enthusiasts it has become a place to see and be seen, and to gain instant access to concepts and ideas that might otherwise go unnoticed. Without doubt, the Internet is good for the growth of model aviation — and good model aviation is certainly good for RC soaring.

I invite readers to contact me via e-mail at wilbyers@aol.com. If you don't yet have an Internet connection but do have a computer, consider contacting an Internet access provider to get online. There are lots of providers; when choosing one, look at your needs not only now but also in the not-too-distant future. Choose a provider that can grow with you.

America Online, Inc. is one service that provides Internet and World Wide Web (WWW) access (it is my provider). Other providers include Prodigy, CompuServe, MS-Net, AppleNet, and many independent providers. Some services offer unique access features tied to their server systems, so make sure a provider meets your needs before signing up.

Getting on the World Wide Web

The Web is a user-friendly evolution of the Internet that links information worldwide. It uses HyperText Markup Language (HTML) and HyperText Transfer Protocol (HTTP), so you click linked text and your browser connects you to the referenced site. Location makes no difference — you can be linked to sites in South Africa, Australia, Japan, or anywhere else nearly at the speed of light.

I suggest starting with a good search site such as Yahoo: http://www.yahoo.com. Type a search term (for example, SOARING) and follow the links (HTTP) to find sites of interest. The experience is fun and yields lots of useful information.

Suggested soaring sites

These are only a few of the hundreds of sites available. Log on, check them out, learn a lot, and have a great time browsing the Web.

C.R. AIRCRAFT

Those of you who have participated in slope soaring for some time may know Charlie Richardson of C.R. Aircraft. His company has grown to include many diverse designs and is one of the few companies focused specifically on slope soaring.

C.R. Aircraft offers a wide array of slope gliders dedicated to performance in slope conditions. Their product line ranges from 72-inch wings like the Contender to the Raider Unlimited Class racer. Features common to their models include:

  • High-quality molded epoxy/fiberglass fuselages, some reinforced with Kevlar or graphite
  • Beautifully crafted slip-on nose cones
  • Vacuum-bagged wings and noted craftsmanship

Notable models

Renegade

  • High-performance 60-inch-span slope racer
  • RG-15 airfoil, vacuum-bagged wing
  • Wing area: 420 in²; wing loading up to 12 oz/ft^2 (to FAI max)
  • Structural integrity to carry more than two pounds of ballast
  • Flaperon system for efficient, high-G pylon turns
  • Stable at all speeds with good light-lift and thermal ability

Raider (Unlimited Class racer)

  • 96-inch-span wing
  • RG-15 airfoil; aspect ratio 11.5
  • Surface area: 950 in²; wing loading up to 14 oz/ft^2 (to FAI max)
  • Highly prefabricated — requires only radio installation and paint
  • Designed for the full-blown flier/race pilot

Other models in the line include the Contender, Turbo, Climax (a great hand-launch glider), and the Excel.

Accessories and materials

C.R. Aircraft also offers a range of sailplane-related items, such as:

  • Carbon-fiber wing rods
  • Nylon screws and composite control horns
  • Mylar hinge tape
  • R/C chargers, receivers, and servos
  • Sanyo NiCad batteries
  • Feather Cut systems
  • Spyderfoam wing cores

Spyderfoam is a foam made specifically for composite construction. It offers about three times the compression strength of conventional blue foam and better shear properties; its cell structure provides improved bonding to wing skins. Spyderfoam is roughly 10% heavier than blue foam, but its increased compression strength allows for lighter wing-skin layups. It can be wire-cut but should be cut with 0.02 in. or 0.03 in. wire only.

The Swift — new scale offering

C.R. is tooling up to produce its first entry in the scale arena: the Swift. This will be a near-scale, aerobatic-oriented slope model with beautiful lines based on the full-scale FAI contest Swift. Key points:

  • 100-inch-span version in development
  • Available with either RG-15 or Helmut Quabeck (HQ) 2.09 airfoils
  • Wing options: flaps + ailerons or spoilers + ailerons
  • Wings sheeted in obeche or vacuum-bagged (your choice)
  • Wing area designed to be around 800 in²
  • Fuselage and control surfaces nearly scale with minor changes to improve handling

If you want a hot scale slope model, the Swift from C.R. looks promising.

C.R. Aircraft Models contact: 205 Camille Way, Vista, CA 92083 Tel: (619) 630-8775

For a three-view and Foto-Pak of the Swift, contact Scale Model Research: 3114 Yukon Avenue, Costa Mesa, CA 92626 Tel: (714) 979-8058

Airfoil of the Month: HQ 2.09

No surprise this month — the HQ 2.09, used on the C.R. Swift.

  • Designed by Dr. Helmut Quabeck for the F3B competition arena
  • Camber: ~2%; thickness: ~9% of chord
  • Wide drag bucket and broad speed range
  • Moderate pitching moment; tolerates a slightly aft center of gravity (CG)
  • Well suited to flaps — place flaps at approximately 21% of chord measured from the trailing edge

The HQ 2.09 can be an excellent choice for the Swift or for your homebrew. Quabeck sections can be somewhat particular about CG, so take care when setting the CG; the rewards are worth the time spent dialing in the model. If you need coordinates, write or e-mail me and I'll get them to you.

Next time

I'll evaluate Computer-Aided Design (CAD) software and how it relates to designing and building slope soarers, focusing on Ashlar Vellum 3-D and comparing it to five other CAD systems. I'll also keep an ear to the ground for notable slope-soaring tips to share.

Transcribed from original scans by AI. Minor OCR errors may remain.