Old-Timers
Bob Angel | [email protected]
Storing balsa
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.
High-Tech Model Search
Part of the thrill of Old-Timer (OT) free flight (FF) could be the adventuresome search for an errant model. This can occasionally resemble Stanley’s search for Dr. Livingstone in the African jungle. 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, a 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 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 one-sided 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 to hold a wing down and he lost the battle.
If one uses a one-sided elevator, care must be taken in the rigging to minimize any rolling tendency. A little washout and slightly more down travel than up can help. Also, use a slightly stiffer spring or less sensitive linkage so you don't get abrupt deflections. These measures help the model penetrate the wind and make it back across obstacles such as 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 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 U.S. were freezing, they were enjoying 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 well-known and popular U.S. 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.
Coil-Saver Circuit
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 coil-burnout 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 coil-melting 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 0.8 ounce, but it replaces the weight of a servo and a 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 area. It has long been 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.
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 prefer to remain anonymous.
Dave Harding, who is shown holding that cute little Tornado, has volunteered to Contest Director (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.
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
Transcribed from original scans by AI. Minor OCR errors may remain.
