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View Full Version : Sailplanes; Classes, S.I.G.s, and Links


Sky Sharkster
07-03-2006, 04:53 PM
Now that the Sailplane Forum is open to all classes of powered and unpowered gliders, Jason and I have put together some information on the various classes, both AMA and FAI, the Special Interest Groups (SIGs) and links for aircraft and supplies. First, for American Soaring pilots, here are the AMA classes;
Class A - Hand Launch Sailplanes - Span limited to 1-1/2 meters
Class B - Two Meter Sailplanes - Span limited to 2 meters but greater than 1-1/2 meters
Class C -Standard Class Sailplanes - Span limited to 100 inches but greater than 2 meters
Class D -Unlimited Class Sailplanes - span greater than 100 inches
There are other events like Nostalgia, Rudder/ Elevator/Spoilers (RES), Scale. Check your AMA Rulebook for details
Now the Federation Aeronautique Internationale (FAI) classes for Soaring;
F3B - Multi Task Thermal Soaring Gliders
F3F - Slope Soaring Gliders (Provisional)
F3H - Soaring Cross Country Racing (Provisional)
F3I - Aero-Tow Soaring Models (Provisional)
F3J - Thermal Duration Gliders
F3K - Hand Launched R/C Gliders (Provisional)
These are the unpowered gliders in FAI. Electric-Powered Gliders have the prefix F5. This will be covered in a later segment.
The original soaring society in the U.S. is the League Of Silent Flight. http://www.silentflight.org
Rules for FAI Soaring can be found at
http://www.fai.org/aeromodelling/rcsoaring/
There'll be more info coming, Jason has a short history of Discus Launch Gliders in the works and we welcome any helpful additions!
Thermals!
Ron

Sky Sharkster
07-05-2006, 01:21 AM
In this segment, we'll discuss the smallest, and in many ways, simplest, way to fly R/C gliders. Along with slope soaring, HLG requires the least "support" equipment; A transmitter and an airplane.
The accepted size limit for HLG is 1-1/2 meters, slightly less than 60" wingspan. there is also a smaller size called "Micro HLG" or "Mosquito Class HLG" (less than 40" wingspan). Many have built-up balsa wings, some have fiberglass tailbooms and all-composite construction is more and more common. There are kits, ARF's and published plans so the price range can be just a few dollars for balsa stock, to several hundred dollars for an all-composite ARF.
A simple way to get started in HLG is with an inexpensive ARF like the Great Plane's "Fling". This is a 2-channel (rudder/elevator) ARF with F/G nose pod, carbon fiber boom, built-up balsa wing and tail. Price is $59.99.
Other suppliers of HLG ARFs and kits are Art Hobby, NorthEast Sailplane, ICare, Hobby Lobby, Dynaflite, MM Glider Tech, Sky Bench Aerotech, Polecat Aero and DJ Aerotech.
A good introduction to Hand Launch Gliders is here; http://www.fatlion.com/sailplanes/hlg.html
Next up; Discus Launch Gliders, Jason has the info on this fast-growing glider type.
Ron

Jason T
07-05-2006, 02:56 AM
Here is a brief history of Discus Launch Gliders (DLG) courtesy of Paul Naton of http://radiocarbonart.com/

The discus launch style started by Harold Locke, Phil Pearson and Dick Butler in the Seattle area. This was in the 1997-98 time frame. The first DLG planes flew at the big Poway HLG event in 2000 and 1 of the planes placed in the top 10. By 2001, the over hand throw planes were replaced by the spin style and only 2 of the older type planes flew in the 2001 contest.

With the more efficient launch style the DLG's were adapted to very quickly. I have also heard comments that some older pilots were able to start flying hand launch gliders again because the discus launch method is much easier on the body where there is a spinning launch method as opposed to a running and throwing style launch.

Jason

Sky Sharkster
08-14-2006, 03:33 PM
The 2-meter (78-1/2 inches) Thermal Duration Glider class is traditionally the most popular TD event at glider meets. They are large enough to fly well, have good visibility at altitude and are fairly inexpensive. A one-piece wing will fit in most autos and there are literally hundreds of different models available. These range from balsa "Builder" kits, semi or short kits, published plans, composite kits, ARFs and (nearly) RTFs.
2 Meter (and larger) gliders are launched using either a "Hi-Start" or a winch device. The Hi-Start is a 100' length of surgical tubing attached to 400' of monofiliment line. The tubing end is staked to the ground; The opposite (line) end, with a ring tied on, is attached to a towhook on the glider fuselage. The line is pulled backwards, stretching the tubing. Once released, the tubing contracts, pulling the glider forward. The lift of the wings converts this forward motion into an upward climb. When maximum height is reached, the pilot "flys off" the line, free to glide.
The winch is usually an auto starter motor powered by a 12 volt battery. The line is tied to a drum and the motor winds the line onto the drum, pulling the glider forward. The speed of the turning motor is controlled by a foot pedal near the pilot.
Once off the line it's up to the pilot to find "Lift", thermals that are generated by rising warm air. For contests there may be a time limit, like 10 minute flights, with a spot landing task added. There is almost always a number of flights required by each pilot throughout the day (Rounds) to equalize the "Luck" and weather factor.
Model control ranges from the simplest rudder/elevator system to ailerons, spoilers, flaps and mixes like flaperons, spoilerons and "Crow" configuration. Flaps, spoilers and ailerons can also be used to perform camber-changing functions, in effect modifying the airfoil in flight to meet different requirements like slow glide, high-speed cruise, rapid descents and so on.
Designs range from the older "Nostalgia" models, to the venerable Goldberg "Gentle Lady" + "Sophisticated Lady" , Great Planes' "Spirit + Spirit Elite", Dynaflite "Wanderer", "Bobcat" and "Daydream" (these are all-balsa models, also called "Woodies" "Crunchies" or "Gasbags") to the ultra-modern all-composite "Glass Slippers" from companies like rnr sailplanes, mapleleafdesign, airplane-model.com (Vladimirs model), eurosailplanes, f3x, as well as the sites listed under "Hand Launch Gliders" (above). Prices range from less than $100 for a balsa kit to over $1000 for an all-composite competition machine.
Radios for gliders of any type must have the maximum reception range possible; High-quality dual-conversion FM receivers are practically universal and "Fail-Safe" functions are also popular. Many gliders now carry a lightweight altitude-recording device, and "Lost-Model" beepers or tracking devices are not uncommon. Gliders fly higher and farther, for longer periods of time, than any other type of model aircraft, so all systems that will help return it safely are used.
Next segment will be "Slope Gliders and Dynamic Soaring". Stay Tuned!
Thermals,
Ron