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.
Tipperons
The article by Joe Poletti in the February 1984 issue discussed tiperons (tips which rotate about a spanwise axis) as a substitute for ailerons and mentioned that, to the best of the author's knowledge, the idea had never been tried before. In my experience, just about every novel feature of a modern airplane has been tried many decades ago, and in fact, in most cases was patented before 1910.
I am not an aviation historian, but I recall a sailplane built by Hawley Bowlus in the 1930s and flown by Charles Lindbergh that had rotating tips (the flimsy axle bent on each landing and required manual straightening). Also, the Curtiss Tanager, which won the 1929 Guggenheim Safe Airplane Contest, had "full floating ailerons"—rotating tip extensions that controlled roll even beyond the stall. Various NACA reports (TN 316, 1929; TN 336, 1930; TN 458, 1933; TR 424, 1932) present theory and tests on floating-tip controls. The swept flying-wing glider Hill Pterodactyl, circa 1920, featured rotating-tip controllers.
A check through the fascinating book The Lightplane Since 1909, by Underwood and Collings, uncovered a photo of the 1917–18 Martin Kitten, which appeared to use rotating tips for roll control. Start der Wind showed rotating tips on a 1922 glider by Albert Finsterwalder and on a 1924 biplane glider called Peyans Segelflugboot.
There are a number of ways the tips can be actuated to provide roll control and avoid stall. The concept deserves further study, and I hope Mr. Poletti continues his experiments.
Paul B. MacCready Gossamer Ventures Simi Valley, CA
Mars Confusion?
I believe that Mr. Lowe (March 1984 issue, Letters column) may have confused the Martin Mars with the China Clipper. He refers to the Mars being used to carry wounded where, in actuality, the Mars was never put into that kind of service and crashed in the bay while still under test.
My memory fails somewhat, but I believe the props on the first try were 18 ft tip to tip and were constructed of laminated material. These were removed and replaced with aluminum when one fabricated blade let go and passed through the hull just behind the pilots' compartment. When the prop failed, the inboard engine tore loose and was destroyed. These were P&W engines, and if my memory serves, they were about 3,300 hp each. There was only one spare at that time, and it was put in service.
Later (I don't remember how long afterward) a flight on a Sunday afternoon experienced a failure—I've been told it was loss of the leading edge of the rudder. This set up such a vibration that the pilot attempted to land in the outer part of the bay. He set down with such force that it split the hull, and the Mars sank within minutes.
In the salvage attempt, cables were hooked around the wing on each side of the fuselage, and when lift was applied, both sides of the wing sheared off. The entire plane was eventually raised and returned to the hangar. A second ship was under construction, but the war ended before it was finished, and I never knew its outcome. I don't believe it was called the Mars, though.
I worked with Martin throughout the war and was in and about the Mars as well as other planes. However, I was primarily involved with the B-26 bomber.
Hope this is of some help.
Stanley C. Patterson Temple City, CA
TIMM N2T-1
Every once in a while I read in the model magazines that you are always interested in receiving pictures of our (the modelers') latest projects. I'm taking you up on it!
The picture shows the culmination of a two-year project. The plane is a TIMM N2T-1. This was a 1943 all-wood Navy trainer; I believe some 350+ were produced in Southern California. My research indicates that only about four are still flying, so this is a relatively rare type.
In the picture, I'm on the left and Max Hartley is on the right. He and his son restored the full-scale (1:1) aircraft to flying condition. The 2-ft model in the foreground started out as a tiny three-view outline that was on the Navy Erection and Maintenance Manual dated 1943. The model's construction is much the same as the original—all-wood sheeting covered with cloth, then painted. The model weighs 8-1/2 lb, is powered by an H.B. .61 P.D.P., and is controlled with an Airtronics XL radio. It has all the usual flight controls, plus flaps.
Two unique points about this aircraft:
- The wing control-surface hinges are located under the wing.
- The fuel gauge is in the wing surface next to the left walk-up strip—the pilot must look over the cockpit side to see how much fuel he has.
The model duplicates both of these items.
Bob Guilfoyle Ukiah, CA
Statue of Liberty Fund
We sent a check to help with the Statue of Liberty restoration. I want that statue to live on. It's on our tour for visitors. I must have hauled 40 riders around that in 15 years.
The photo shows Bub at age 16, just after soloing (before he grew long hair). I was in a Champ for a picture of him. The Cub's base was just 10 minutes from the statue, when there wasn't any wind.
Hank Clark Dumont, NJ
Those wishing to help with the repairs and restoration of the Statue of Liberty should send donations direct to: The Statue of Liberty Fund, P.O. Box 1986, New York, NY 10018. For more information, see the February 1984 issue, page 96.
Accolades
On a recent quick vacation drive to Florida in December, I had two most enjoyable experiences, which goes to show that unplanned pleasure trips are often the most rewarding. Having read some press regarding the 1983 Tangerine event to be at RC World in Orlando on December 26, I made an unscheduled visit to the site. Due to lousy Tennessee weather at the time, I had been unable to solo a just-completed Precident Lo-Boy 5 (a Hobby Lobby kit), so I had this airplane in the back seat of the car.
My first pleasant experience was the courtesy and hospitality extended me by Bill Sharpe at RC World. This is not intended to be a commercial announcement; however, anyone in our hobby/sport with even a slight interest in moving or retiring to Florida should visit this breathtaking flying site. To those of us accustomed to flying from marginal dirt strips, it is like taking your Piper Cub from a farm lot to JFK International! I had this magnificent facility all to myself for two whole days.
I built the Lo-Boy 5 specifically for the landing flaps and on recommendation that it was a good flier. What a pleasure it was to see the Lo-Boy 5 lift smoothly off the newly paved runway at RC World—right off the building board, with practically no trim required for the rather brisk wind.
Since that dozen or so flights in Florida, I have subsequently accumulated that many more on my small field—and the flaps are exactly what I need. Coming "over the fence," full flaps (approx. 80°) can be deployed with only slight down-trim and no tendency to stall. With little or no headwind, I can set the Lo-Boy down in three-quarters of the field with a roll-out of less than 20 ft. on short-clipped grass. The Lo-Boy 5 is an excellent sport flier and will do all the aerobatics I can handle with only an Enya .45 installed.
Jerry Rivers Goodlettsville, TN
Transcribed from original scans by AI. Minor OCR errors may remain.
