Old-Timers - 2010/04

124 MODEL AVIATION
Storing balsa
Old-Timers Bob Angel | [email protected]
Also included in this column:
• Finding lost models goes high tech
• Single-sided elevators
• New Zealand OT Champs
• New coil-saver ignition unit
• Rosecrans and Western
Above left: John Selby recovers his OT Simplex at the New
Zealand Nationals. Mark Venter of Christchurch NZ submitted
both New Zealand Nationals photos.
Above: Allan Douglas’s wife delivers his Ohlsson & Rice .60-
powered Playboy Senior for a flight during the New Zealand
Nationals.
Left: Dave Harding, who will be the CD at this year’s SAM
Champs, holds the Tornado that flies often in the Rose Bowl
parking lot. Mike Myers photo.
GOOD BALSA WOOD, our most basic
building material, is often sought after,
treasured, hoarded, and saved for years.
Balsa is renowned for its light weight and
workability, but the lighter “contest”
grades are increasingly expensive and hard
to come by.
A recent discussion reminded me that
sometimes stored balsa becomes weak and
brittle with time. Those having this
discussion mentioned temperature,
humidity, and simple exposure to air as
causes of the problem.
I’m inclined to think that it’s mostly
exposure to air, possibly allowing moisture
and maybe oils in the wood to evaporate and
some sort of oxidation or dry rot to occur.
I’ve noticed that framed-up but uncovered
items such as wings seem to weaken with
time, while completed and covered wings
fare better. I’m referring to years—not
weeks or months.
04sig4.QXD_00MSTRPG.QXD 2/23/10 8:54 AM Page 124
I’ve noticed that stacked sheets of balsa
with minimum air exposure remain in good
shape, and balsa, won at contests a few years
ago but kept in its original food-wrapper
coverings, has remained well preserved. If
you have a stash of the good stuff, you might
want to store it in food wrap—or maybe it
should go into an airtight, fireproof safe
along with other valuables.
High-Tech Model Search: Part of the
thrill of Old-Timer (OT) FF could be the
adventuresome search for an errant
model. This can occasionally resemble
Stanley’s search for Doctor Livingston in
the African jungle.
126 MODEL AVIATION
It happens to RC models also, but less
frequently. “The Battery Clinic” columnist
Red Scholefield passed on some useful
information on a high-tech search method.
“Yesterday, my flying buddy lost his
Bird of Time (converted to electric). It
went into a gentle turn and there was no
control. It was last seen descending into
some thick Florida scrubland. A ground
search yielded nothing.
“Then one member with access to a
plane flew over the area later that
afternoon and was able to spot the Bird of
Time. With the aid of a detailed Google
Earth map of the area he pinpointed the
location such that we were able to walk
right to it this morning.
“Next time you lose one, Google Earth
map may be a handy asset in finding it.
Having a friend with a plane is not such a
bad idea either.”
Red entered the Bird of Time’s
location on a copy of the Google Earth
map and posted an e-mail of the picture.
In this case, the surrounding terrain was
distinctive enough to easily find the
model.
But for more difficult terrain, with
maybe a model hiding in a treetop, the air
search can go one step further with
modern technology. The pilot can pinpoint
the model with a Global Positioning
System (GPS) unit. The location can then
be used by the ground searchers with a
portable GPS.
Did I just hear someone scream,
“That’s not the way we did it in the
1930s!”?
One-Sided Elevators: Many OT FF plans
must be modified for RC flying, to include
movable rudder and elevator(s). One
simpler and lighter method of
accomplishing this is to make a single
movable elevator on either the right or left
side.
This can also make the model slightly
cleaner aerodynamically when it’s in a
stable glide. It usually works okay and
seems reasonably practical, especially on
slow, gentle-flying airplanes such as
Texaco models.
I’ve never used or liked the idea of onesided
elevators; mostly it disturbs my
sense of symmetry. Still, that sort of thing
doesn’t seem to bother serious CL Speed
fliers, so maybe an OT competitor who’s
more serious than I am wouldn’t worry
about it either.
On the negative side, a slight torque or
rolling action results whenever that
asymmetrical surface is moved. That’s
unlikely to contribute to smooth control,
especially on hot models during the climb.
I once timed for a man whose one-sided
elevator caused an off-field landing and a
zero flight score. There was a stiff breeze
and his airplane had gotten downwind. He
was holding full down-elevator, but he
didn’t have quite enough control authority
04sig4.QXD_00MSTRPG.QXD 2/23/10 8:54 AM Page 126
to penetrate the wind and make it back
across a low fence to the field boundary.
New Zealand OT Champs: Mark Venter,
an active Society of Antique Modelers
(SAM) member from Christchurch, New
Zealand, sent me an e-mail report and
pictures of vintage events at the New
Zealand Nationals. They were held in late
December 2009. While many of us in the
US were freezing, they were enjoying the
80° summer weather.
The photo of Allan Douglas with his
wife (and pit crew) was taken on a very
windy day. Mark’s comments follow.
“Wind was around 35 mph and most
flights ended with sudden (and generally
terminal) impact.
“One modeler who laughed at the wind
was Allan Douglas. He put his full-size
Playboy Senior up a number of times and it
was a most amazing sight to see it hanging
up there, nose into the wind, while lower
down many other models were either
disappearing downwind at a great rate or
returning to terra firma at high speed.
“Allan’s wife did the retrieving and the
farthest she had to walk was probably
around 200 yards while some of the
smaller models ended up many miles
away.”
The Playboy, circa 1940, is a wellknown
and popular US design by Joe
Elgin. The Cleveland Model Company
kitted the aircraft in several sizes.
It’s as competitive as the popular Lanzo
Bomber but is seen less frequently because
it’s not quite old enough to compete in
SAM’s Antique category. The Bomber can
compete in either Antique (pre-1939) or the
newer (pre-1943) OT events.
I mentioned a coil-saver circuit in my June
2009 column. When a spark-ignition engine
stops with the points closed, the spark coil
can overheat and be damaged if battery
power isn’t switched off right away.
This sometimes happens to an RC
airplane if the engine quits by itself and the
pilot forgets to switch the ignition system
off. And an FF model can’t normally be
switched off until it’s recovered sometime
later.
OT CL fliers have also reported coilburnout
problems, although they can get to
their aircraft quickly after engine shutoff.
A coil saver automatically switches off
the ignition system after the points have
been continually closed for a short time
period. The original circuit was published
in 1976 as a do-it-yourself construction
project.
I mentioned in the earlier column that it
would be nice if someone would update
that circuit to a more modern version with
possibly a smaller parts count. Larry
Davidson, who supplies many of our
ignition components, has done so. He was
aided by Don Hutchinson, who is into
circuits and has experienced the coilmelting
problem on OT CL spark-ignition
engines.
Larry is now supplying ready-made
units combined into a transistorized trigger
circuit that fires the coil with lower
amperage flowing through the points. The
transistor circuit produces a hotter spark
with less erosion of the breaker points.
Larry’s unit shuts down the battery
power whenever the points are closed, for
approximately two seconds. It switches
back on when the points are opened again.
The unit weighs 23 grams, or .8 ounce,
but it replaces the weight of a servo and
microswitch. It comes with wires extended
from the PC board along with wiring
instructions. The coil-saver circuit is
$45.50, including postage and handling.
Rosecrans and Western: That name
conjures up numerous fond memories for
many West Coast OT fliers. It was once
the site of an active flying field in the Los
Angeles, California, area. It has been long
lost to “progress” and is just another busy
metropolitan intersection today.
I wasn’t lucky enough to have flown there,
but I’ve heard many stories throughout the
years from veterans of general flying and
various events held there.
I’d like to collect anecdotes from
anyone who has tales to tell about people,
models, and activities from those days.
The purpose is to gather information for
future columns, or more likely a feature
article, about OT activities.
I’m sure there are other “Rosecrans and
Western”s in the East and all points in
between, where readers have experiences to
recount. Please take the time to add to the
recorded history of early modeling. My
contact information is in the “Sources”
listing.
Writer credit will be given unless you’re
wanted for something and would prefer to
remain anonymous.
Dave Harding, who is shown holding that
cute little Tornado, has volunteered to CD this
year’s SAM Champs. The model was built by
Allan Laycock in Australia and sent to Mike
Myers as a gift.
Mike shared it with Dave to fly when he
came to Pasadena, California, to visit his
daughter. The design is under consideration
for SAM competition eligibility, but its
practical use is for fun and park flying. MA
Sources:
SAM
www.antiquemodeler.org
Larry Davidson
(540) 721-4563
[email protected]
Google Earth
www.earth.google.com
Bob Angel
1001 Patterson Rd.
Santa Maria CA 93455