15TH ANNUAL ARIZONA JET RALLY

Model Airplane News, Apr 2004 by Bell, Rick

A HOTBED OF JET ACTIVITY

Close your eyes and imagine a paved runway that's 800 feet long and 85 feet wide. Then imagine a pavilion with plenty of worktables that stretches 250 feet and provides comfortable shade from the ever-present sun. While you're at it, place this flying site in an area that has more air space than you'll ever need and a climate that allows modelers to fly year round. Sounds like heaven, doesn't it?

Well, this flying site does exist in Mesa, AZ. It's the Superstition Airpark, home of the Arizona Model Aviators, where the 15th annual Arizona Jet Rally took place last November. When I arrived, the sky was a brilliant blue and the temperature was in the high 70s-a welcome change from the cold and snow that Connecticut was experiencing. So it did, indeed, feel as though I were in heaven! Not only was the weather awesome, but so was the flying, with many spectacular jets in the air at all times.

ON THE TARMAC

It had been many years since I had attended an all-jet event. True turbines in models were unheard of then but were talked about often. Ducted-fan models had just started to achieve real performance, and electric jet models were considered impossible. Boy, have things changed! Turbine-powered models are now commonplace for true jet performance and have all but replaced glow-powered ducted-fan models. In fact, electric jets outnumbered glow-powered ducted-fan models at the Jet Rally by almost 3 to 1!

This year, 77 pilots brought more than 100 jet models of all types and sizes, including sport and scale. I don't know whether anyone kept a log of flights flown, but throughout the three-day event, there were very few moments during which at least two jets weren't lighting the fires! Many impressive models were on hand-some nothing short of spectacular, and Ken Wagner's Aeroloft Designs F-104 Starfighter attracted the most attention. When it first appeared in the mid-1950s, the F-104, with its futuristic look, small wing and needle nose, earned the nickname of "Missile with a man in it." The F-104 was the first operational interceptor capable of sustained speeds above Mach 2.0 and was the first aircraft to hold the world speed and altitude records simultaneously. Though Ken's jet is large at 1/7 scale, it spans only 44 ½ inches and is 94 inches long, and it's powered by a RAm 500 turbine.

When Ken readied this beauty for flight and fired up the turbine, rest assured that he owned the flightline! Everyone watched as he taxied the jet onto the runway, turned it into the prevailing wind and quickly accelerated. Even though the F-104 looks as if it shouldn't be able to fly with its impossibly small wing, the jet gracefully lifted off and convincingly climbed away as the gear retracted. After a few passes and with the fuel load quickly decreasing, the Starfighter really came to life as it streaked across the Arizona sky. A huge cheer from spectators and pilots erupted when Ken skillfully landed the jet and taxied it back to the pits. What a breathtaking flight!

This was only the beginning of many spectacular flights, as TamJets' Tam Nguyen and his team demonstrated what their ViperJet MK IIs could do. It seemed that every time you turned around, a ViperJet MK II was airborne. Their flights were outstanding, especially when they turned on the smoke. Very cool!

By far the most popular jets on the scene were BVM's BobCats and the new, larger, KingCat. Both jets are cool looking and excellent flying models. The KingCat has a very wide performance envelope, and I was quite impressed to see one land at a walking pace with a 3-foot rollout.

SCALE SPEEDSTERS

All three days of the event were bright and sunny, but temperatures on Saturday and Sunday fell to the lower 50s, and the wind steadily increased. This, however, didn't deter the scale jocks from taking to the air with a great variety of jets: F-16 Fighting Falcons, F-15 Eagles, F/A-18 Hornets, F-86 Sabres were just a few of the scale beauties. The wind did play havoc with models that had narrow-track landing gear; when these turned crosswind, a badly timed gust could lift and drag a wingtip, or worse-flip them completely over. F-16s were the most vulnerable to these conditions.

"Watts UP" WitH eLectric Jets

One of the biggest surprises was the large number and huge variety of electric ducted-fan (EDF) jets. They ranged from small jet-like models to converted glow-powered warbirds to a scratch-built, 137-inch-span model of Burt Rutan's X-Prize contender White Knight. These models and more made many flights despite the strong wind.

Given the sizable contingent of EDFs present, I'd say that their development is at the stage where glow-powered ducted-fan jets were when they first appeared on the scene. What makes this segment so popular is the latest batch of high-performance brushless motors from Hacker, Mega and AstroFlight and a host of other manufacturers. The other part of the equation is the power source: the all-important battery. Lithium-polymer (Li-poly) batteries, though in their infancy, are playing a key role and are showing vast improvement as they mature. The EDFs at this year's event certainly generated a lot of interest with their increased performance and duration. Here are some of the highlights: