ElectricFlight A
s I write this column, I have just gotten back from the biennial FAC Nats in Geneseo, NY. A really nifty freeflight contest, whose rub- ber power aspects will be fully covered next month in this magazine. My focus this month is therefore on freeflight rather than R/C. Let’s take a look at the Power Scale event at the Nats. The rules add bonus points for non-electric power since electric power has some advantages. However this year all the winners used electric power. The energy density advantage of Li-Pos make them and a timer more or less a given for a winning model. Well almost ... Ted Allebone, unfortunately not at this year’s Nats due to a health emergency, still uses Ni-Cds and Ni-MH cells. The rules for this event emphasize the scale aspect of the model rather than the fly- ing time, by factoring flying time. A maxi- mum of 82.5 flight points can be awarded for each flight. For the first 60 seconds each sec- ond counts as one point; the next 30 seconds add a half point per second; and finally above 90 seconds each second adds one quarter point up to 120 seconds. Over 120 seconds, no points—boasting rights only! It’s rather assumed that any model is capable of a two-minute max. Flights under 20 seconds are non-official and can be reflown. During scale judging, points are awarded for Construction (how much detail of the real aircraft is represented on the model), Mark- ings, and Workmanship. The rules also add bonus points for multi wings, multi engines, floats, and non-conventional configurations. Don Srull took full advantage of these rules to win the event with his Westland Ptero- dactyl. Martin Richey was second with his ducted fan Blohm and Voss P. 212.03. Biplanes finished the winners list with Thomas Hallman’s Peanut Airco DH-2
by stew meyers You can reach Stew Meyers at 8304 Whitman Drive, Bethesda, Maryland 20817, or via e-mail at
stew.meyers@
verizon.net
Mike Escalante and Pete Kaiteris begin judging Doug Beardsworth’s electric powered Curtis BF2C1. PHOTO: BONNIE SIMPERS
third, Derek Knight’s DH-82 Tiger Moth fourth, and Doug Beardsworth’s Curtiss BF2C1 fifth. Since I know these guys, I pre- vailed upon them to supply me with the complete power system setup in each model. Let’s look at each model in turn. Master modeler, Don Srull, is an old pro at electric power. He and Tom Schmitt start- ed Hi-Line 25 years ago. His 32-inch span Westland-Hill Pterodactyl Mk VII weighs 104 grams and is a model of a proposed fly- ing wing seaplane with four motors, two of which are pushers, netting him 43 bonus
points. Power is supplied by four KP 00s turning 4-inch GWS props, using a single Li- Po cell of 300 mAh capacity. The motor timer is the KP 2-minute ver- sion, driving a 20-amp Mikro ESC which is set to a 2.8 volt cutoff. All motors are wired in parallel to the single cell. Don maxed on all flights using a single charge on the bat- tery, and his scale and bonus points made him the winner.
Martin Richey worked as an engineer in turbo design and has been a pioneer in mi- cro ducted fans. His second place model, the
PHOTO: BONNIE SIMPERS
The BF2C1 Goshawkawaits judging on top of its documentation (above left). Motor, timer, and battery are all located on a removable balsa tray (above right)
42
PHOTO: DOUG BEARDSWORTH
held in place by magnets on the BF2C1. Battery access as well as the other electronics are easily accessible.
NOVEMBER 2012
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