[Headline: Thermix-13 PF]
Q605: In the August 2014 issue of Model Aviation, Dick Sarpolus published a Thermic 100 variation that he called the Thermix ’13. This large model has 900 square inches of wing area and weighs 60-70 ounces. I really loved this airplane, but it is way too big for my liking. I have a small car and a limited hobby budget. Is there any way that this lovely airplane could be reduced in size to meet my requirements?
A605: I have to agree with you that Dick came up with a real winner in this design. The Thermic series was one of the most popular sailplane designs over the years. Dick’s rendition, with its semi pod-and-boom fuselage made it attractive and easy to build.
I contacted Dick, who is a fellow AMA Model Aviation Hall of Fame member. We have been friends for many years. Dick indicated that several readers contacted him about a reduced-size Thermix ’13. On the spot I asked Dick if he had any objections to me doing a reduced-size version. What I had in mind was a 275-square-inch wing area that would essentially make the airplane the size of a park flyer.
I took up the challenge, with Dick’s permission, and ended up with an airplane that I call the Thermix-13 PF (PF for park flyer). My resulting reduced-size airplane came out surprisingly lightweight—only 9.7 ounces. To make it available in a reasonable amount of time, I published my version in the November 2014 issue of the RC Micro World webzine.
I’ve included photos of Dick’s version, as well as my own, in this column. Note that I copied Dick’s color scheme exactly.
The reduced-size version flies just great! I’m hoping to get together with Dick and fly our two versions side by side, and that one of our hobby manufacturers will contemplate making a laser-cut parts kit or semi-kit of both designs.
Q606: In the late 1950s, single-channel (one control function) RC systems began to be replaced by what we called “resonant reed” or simply “reeds.” I would like to revisit some of this old-time RC equipment with the hope of participating in the Vintage RC Society gatherings held throughout the country each year.
I’m sure I could buy some of this old equipment on eBay or one of the RC forums, but I was wondering if there might be any other way to emulate this kind of RC control?
A606: Noted RC author and manufacturer, Cal Orr, has come up with a perfect idea that should interest many of our readers. What Cal has done is create what he calls the CalAire Reed Emulator. It is contained in a box that attaches to your 2.4 GHz RC transmitter.
This “box” acts much like a buddy box. As you can see in the photos, the Emulator has the button and toggle switches as used in old RC reed transmitters. Nearly any three- or four-channel airplane can be flown on reeds—or at least feel like it operates on reeds—and there is no modification needed on your transmitter or aircraft.
When the Emulator is switched on, the servo transit time is increased to simulate that of reed servos. At any time the Emulator can be turned off and full control is returned to the primary RC transmitter.
There is also a feature that allows the Emulator to operate like an old escapement system. This lets you push one for right, two for left, and three for up and down in sequence.
Cal isn’t sure if he plans to manufacture this Emulator, but he has given me permission to list his email address (see “Sources”) in case you have any questions for him. I’m sure many Vintage RC Society members will be interested in this item.
My thanks to you, Cal, as always!
Special F3P Model
Q607: I recently saw an action video of a carbon-fiber F3P electric-powered indoor aerobatic model designed and manufactured in Europe. Unfortunately, I lost my reference source. I’d like to be able to share this design with fellow Model Aviation readers. Can you help me?
A607: I didn’t have much to go on, but Gordon Johnson, a noted Indoor RC specialist, came to my rescue. The airplane you are interested in is called the Victory 1S. It was designed by a European modeler, named Donatas Pauzuolis.
The airplane is made from carbon-fiber rods, has a 32-inch wingspan, and weighs only 37 grams. The heart of this design features a coaxial, dual-propeller assembly designed by Alexey Lantsov. A photo of that drive is included in this column.
I’ve listed the YouTube video link in the “Sources” section, along with Donatas’ email and website addresses. You won’t believe the performance of this model as shown in the video.
I gather this remarkable airplane will be offered as a complete kit along with the extraordinary motor drive system. If you are a serious F3P pilot, this may be the airplane for you.[dingbat]
RC Micro World
Vintage RC Society
Carbon-fiber F3P model video