Do you remember that those flaperons could also
be coupled, CL Stunt (Precision Aerobatics) style, to the elevator? The
result was even more increased stability and some exciting stunts.
With
full elevator input, the flaperons were set to move approximately 20°
(roughly 60% of maximum). The result was sharp-cornered,
50-foot-per-side square loops, upright or inverted. The Hobbistar 60 did
not drop a wingtip, even with sudden, and full, elevator input.
Without
the coupled flaperons, the left wing would drop, but not tip stall,
while enduring such piloting abuse. The corners were not as sharp and
the loop radius was much larger.
The stock Hobbistar 60 does exhibit
some adverse yaw at slow speeds and does not roll well. The rolls are
not truly axial, maneuvering along the flightline; they wander above and
below the flightline as the roll progresses. Part of this is caused by
the adverse yaw and differing aileron drag.
Adding 18% (Futaba
settings—other radios may vary) differential to the airplane's aileron
movements reduced this problem. The rolls improved and were basically as
near axial as with any high-wing aircraft. Slow flight and stalls
remained level, and the adverse roll disappeared.
There is just one
caveat about flaperon use. Many new pilots learn by using the buddy-box
system, where two transmitters work in conjunction. When using this
technique on an airplane with flaperons, both transmitters must be
computer based. Using an analog transmitter as the student's control box
results in just one aileron moving. Set the "buddy" transmitter to the
flaperon format for proper aileron operation.
Space does not allow me to
fully detail all aspects of the modified Hobbistar 60's flight
performance. If you want to know more, visit
Sport Aviator's Test Pilot
Reports section. There are even three videos showing this airplane's
performance abilities.
The flight tests proved that the extra work was
very much worth it. The modified Hobbistar 60 is going to stay in my
hangar for a long time.
Click on photo to view large image with caption
This is usually where I write about next month's
"From the Ground Up" article, but not so this time. It's hard to
believe, but the engine and airframe sections of this groundbreaking MA
series have been running for 12 of the last 13 months. In that time I
hope to have passed along some of the things I learned the hard way
while helping new pilots have the fun and excitement they expect when
they join the model-aviation community.
I thank MA Technical Editor Bob Aberle for inventing this landmark series and Aeromodeling Editor Bob
Hunt for allowing me this opportunity. A special thank you to Dean
Pappas for helping with many of the more intricate technical details.
But most of all, thank you for reading these segments and for the many
encouraging words, letters, and phone calls I have received during the
past year. They meant a great deal to me, and I truly appreciate them.
I
learned many new things researching these articles and even more from
those readers who made some needed corrections along the way. Thank you
to everyone, and I hope to get a chance someday to fly with you all
before my propeller turns for the last time. See you at the field! MA
Frank Granelli
granellif@aol.com
Aircraft specifications:
Engine used: O.S. Max .61 FSR
Propeller: APC 12 x 6
Top rpm: 11,500 rpm
Idle rpm:
2,200 rpm
Test weight: 7 pounds, 14 ounces
CG location: as directed
Elevator movement: 7/8 inch up and down
Aileron movement: 7/16 inch up
and 3/8 inch down
Rudder movement: 11/4 inches
Weather data:
Temperature: 72 degrees Fahrenheit
Wind: 10-12 mph
Altitude: 250 feet
Sources:
Harry B. Higley & Sons, Inc.
Box 532 Glenwood IL 60425
www.members.aol.com/harryhig
Hobbico, Futaba, Great Planes:
Great Planes
Model Distributors
Box 9021
Champaign IL 61826
www.greatplanes.com
Horizon Hobby, Inc.
4105 Fieldstone Rd.
Champaign IL 61822
(217)
352-1913
www.horizonhobby.com
Prather Products, Inc.
1638 Cowles St.
Long Beach CA 90813
(310) 835-4764
www.pratherproducts.com
