Hi Spy (oz2129)


Hi Spy (oz2129) by Hal Roth 1954 - plan thumbnail

About this Plan

Hi Spy. California contest model. Free flight power. Atwood engine shown.

Update 07/06/2021: Added article, thanks to akvose.

Quote: "From out of the west comes this ultra simple high-performance engine-in-wing pylon, by Hal Roth.

HI-SPY California Contest Plane. To win contests you've got to get up high - and do it often. Most conventional models entered in competition have plenty of potential climb but usually waste at least half of it doing loops, dangerous spins, fall-offs, stalls and other maneuvers better left for the control line stunt flyers.

Hi-Spy's best and smartest attribute is a grooved climb. The model climbs straight, no turn, no loop, no violent circles, no wasted power. Just up. Up at 75 degrees for the full 20 seconds of motor run. When the motor shuts off, the ship is high enough to glide for five minutes.

No fooling! Try this high engine pylon set-up. Take any pylon model you have and mount the fan up high and go set for yourself. Adjusted to climb straight. the ship ascends without any lost motion, using all the forward impetus to build up climbing speed. There is no looping or spinning tendency because the pro-peller slipstream (methinks) is above the pylon, fuselage side area, and rudder.

Hi-Spy is big for a Half-A model. The wing has 300 square inches of area, but don't try .099 engine; too powerful.

Complete construction details available on full-size plans."

Supplementary file notes

Planfile includes full build instructions.


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Hi Spy (oz2129) by Hal Roth 1954 - model pic


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