Letters To The Editor
All letters will be carefully considered; those of general interest will be used. Send to Model Aviation, 1810 Samuel Morse Dr., Reston, VA 22090.
Dragonfly P-30
My article in the April 1988 issue contains a small but important error. This needs to be corrected not only to help Dragonfly builders but to avoid misleading other P-30 fliers—or even Coupe fliers who also use 10-gram motors.
I listed the weight of a 10-gram motor of 7/16-in. width as being about 76 in. long. Right after the magazine appeared a couple of callers informed me that this length is wrong. A check with my friend's industrial gram scale, accurate to two decimal places, confirms that lubricated 7/16-in. rubber of 10.0 grams is 91 in. long. Apparently my inexpensive gram scale led me astray.
The bad news is that a mistake was made. The good news is that a 90-in.-long motor instead of 76-in., pretensioned (corded) to fit the 19-in. distance between hooks, will deliver an 18% increase in duration, putting the model at around the 2-min. mark.
Dave Platt Plantation, FL
More
The April article in Model Aviation on the Dragonfly P-30 by Dave Platt was good, and we need more good articles on Free Flight activities. But I would like to point out the lack of a snuffer tube on the plans. With the current emphasis on safety, this should be an important factor. Mr. Platt intended this to be a competitive airplane, and as such a snuffer tube is required in competition.
Bonny Jenkins Chairperson, Free Flight Contest Board Memphis, TN
Bonny is right, of course. Designer Platt says the aluminum snuffer tube is installed in a rudder cutout just above the stabilizer—as shown on a portion of the revised plan.
Box Floats Work
Just a note and some pictures that may be of interest. Yes, a vintage "old timer" like me can learn to fly RC helicopters. No, I couldn't find any custom floats for the GMP Shuttle, so I made these ugly boxes just to see if floats would work. They did. What a blast to taxi on and fly off water.
I am flying the new "high mast" Shuttle and must say it is a great improvement. A 1,200 mAh pack handles the Futaba radio with five servos and gyro very nicely. The O.S. .32 engine is more than adequate for float flying with this model.
Norman Hanson Hilton Head Isle, SC
1½-V Batteries
I read with great interest the letter from Lee Hoffman in the April 1988 issue regarding the lack of availability of 1½-volt batteries.
I'd like to pass on an idea that I've used for years, before going to a rechargeable Ni-Cd starter. Simply buy a 6V dry cell (available almost anywhere for about $3) and remove the case. Inside are four 1½-V cells which can be used individually or rewired in parallel for an ignition battery which can last all season.
Actually I prefer this to a Ni-Cd because it doesn't go "flat" without warning.
Gene Zdenek Berwyn, IL
Calhoun Smith
I read your April 1988 issue with great sadness. I refer to the Sportwagon which was originally designed by Cal Smith.
In my opinion Cal was the finest human being I have ever met. Our paths crossed in 1955 at The Daily Mirror Air Show on Long Island at Grumman Field. We were both entered in the Navy Carrier event, which he won.
I came home that night and sent away for a set of plans of the Douglas Skyraider that Cal used in the event. He told me that if I wanted to win, this plane is what I needed. I forget, now, who sold the plans, but anyhow I followed Cal's advice.
The following year we met again, only this time I also had a Skyraider just like his. He took one look at my plane, gave me a big handshake, and withdrew his plane from the event and helped me, allowing me to win.
That day I was the happiest kid in New York City—only because Cal was that kind of a guy. Your article about him was fantastic. I remember him well. If I could find another set of his plans, I would build another Skyraider. Just for him.
Jim Meikle Peekskill, NY
Transcribed from original scans by AI. Minor OCR errors may remain.
