A new column exploring the big picture

Model Airplane News, Mar 1998 by Yarrish, Gerry

Can you remember your first big model? What was its wingspan? For me, my first really "big" airplane was a Goldberg Sr. Falcon, back in 1970. It had a whopping, 69-inch wingspan and if memory serves me, I believe it had about 800 square inches of area. By today's standards, the size of the old Sr. Falcon is nothing special. Size is a relative thing, and today really big usually means huge.

The definition of big has changed over the years, and recently I saw this clearly. I was at an IMAA fly in and had brought along my Hangar 9 ARF Cub and Ziroli Stearman PT-17. As I was setting up my tent, someone came by and commented on how small my 80-inch Piper Cub looked compared to the rest of the models. Boy, how times have changed.

The International Miniature Aircraft Association (IMAA) has had much to do with the popularity of big R/C, and many modelers are stepping up to the 80-inch and larger formats. A trip to almost any RIC flying field today will yield at least one giant-size model. Plans are now available from many sources for truly gigantic models, and events such as the TOC and Top Gun bring very large models together for competition.

Because of this continued interest in building and flying large models, we've decided to reintroduce a column that addresses these big issues. Every other month, we'll look at gasoline engines and other big bore powerplants: we'll highlight models and events; and we'll discuss new big bird products. I'll also touch on construction techniques and materials that I hope you'll all find useful whether you're a big bird builder or not.

So far I have not used the words "giant scale." My intention with "Thinking Big" is to address sport models as well as scale models and to talk about IMAA legal models as well as those with 79-inch wingspans (and maybe even smaller). If this brings letters of disapproval from you dyed-inthe-wool IMAA'ers, I'm sorry, but this column is intended for the sport modeler. I'd like to start right now and ask for any questions. If you are a newcomer to big and giant-size models, then I'd like to hear from you.

A NEW BABY

While on the subject of just starting out, if you're in the market for a first-time big bird, why not consider the new Fly Baby kit from Dynaflite*. Though I have not yet built or flown one, I have looked inside the new kit, and it looks very promising. The plans are CAD drawn, and the quality of the wood is good. The plywood is die-cut and very clean in appearance (no die-crunching). Being 1/4-scale, the Fly Baby has an 84-inch wingspan and the suggested weight is 11 to 13 pounds. With an area of 1,059 square inches, that equates to a loading of about 26.3 ounces per square foot (at 12 pounds); good numbers for a first time 7-footer. The cowl is typical twopiece, vacuumformed plastic (split vertically), and the kit comes with basic hardware and stout, bent music-wire landing gear. Personally, I would slap a Saito .914-stroke engine in this one, but you could just as easily power it with a .90 2-stroke or a 23- to 25cc gasoline engine. I'll bet we'll see a lot of these models at the local flying field in the coming season.

SHULMAN SUCCESS

I just got some information from Leon Shulman about his grandson Jason, who won the 1997 Masters World Aerobatic Championships (MWAC). Held at Hartness Field in Greenville, SC, the MWAC brought together 21 of the leading R/C pilots to compete at the same site that hosts the annual Joe Nall IMAA fly in. As with the Las Vegas Tournament of Champions, the MWAC has three segments of competition; the "Known" pattern, the "Unknown" pattem and the very popular "4-minute Free Style." Scoring is based on 40 percent each for the Known and Unknown segments and 20 percent for the Free Style.

New maneuvers, known as 3D aerobatics, are all the rage now in giant-scale aerobatic competition, and the MWAC was no exception. Rolling loops, slowspeed inverted outside loops, and lowlevel hovers (torque rolls) are the norm. When the dust cleared, Jason had won his second consecutive MWAC. Mike McConville came in second, and Frank Noll was in third place.

Jason's aircraft is a Pirate Models* 37-percent scale CAP 232 powered by a 3W* 120 twin-cylinder engine swinging a 28x10 Menz "S" wood prop. Jason's 35-pound model is made of lite-ply, balsa and foam and has a wingspan of 107 inches. As can be seen in one of the photos, Jason has no problem bringing his CAP down on the deck in a hover. I wonder how many bent rudders do you have before you get this good?

HALF-SCALE EXTRA

Some guys just do it right when they build an airplane, and Jacques Lapointe of St. Georges, Quebec, Canada, did so in a big way. I met Jacques a while ago at the Glens Falls, NY, Balloon Festival, where he was flying with the Master Flyers Air Show Team. When I saw his big Extra, I was blown away. Jacques' 50-percent Extra 300S is a modified, Aerotech R/C Models* kit, and it's powered by a 3W 240 B4, 4-cylinder (20hp) engine. The engine spins a 34x12 prop and produces about 110 pounds of static thrust. The wingspan is 13 feet and the model has 4,363 square inches of wing area. With an all-up weight of 74.5 pounds, the wing loading is a very respectable 39.5 ounces per square foot. Construction time was around 1,200 hours. I think you'll agree Jacques' time was well spent.