FF Sport

Author: Gene Smith

Edition: Model Aviation - 2013/05
Page Numbers: 133, 134, 135

Dave Gee’s impressive Dumas B-26 Marauder

This year’s One Design model for the AMA Nats is the 1/2A Satellite. A kit for the 320 is available from BMJR Models. Plans for the 226 and the 320 are available from the National Free Flight Society (NFFS) and the AMA Plans Service.

Bob Holman Strip Clips

Bob Holman has several model-building aids, including a new one he calls “strip clips.” The clips allow you to build the second fuselage side directly over the first. The two-piece clips are laser cut from Lite Ply. I glued mine together with CA+ adhesive.

The photo with this column shows my Wanderer’s fuselage sides in the clip fixtures. You could also use a clip to help align the fuselage verticals, but I elected to “freehand” them. The clips are available for several strip sizes. The ones shown are 1/8 inch. Check Bob’s website, listed in “Sources,” for pricing.

Stuka Dave’s Marauder

Most of you are familiar with this magazine’s “Safety Comes First” column by “Stuka Dave” Gee. It would be an understatement to say I was impressed with the speed at which Dave built a Dumas B-26 Marauder early last summer.

He gave much of the credit to the kit, which he says has laser-cut parts that fit perfectly. One day he had pictures of the components on the building board, the next day they were assembled, and the following day the model made its first test glides.

The motivation for the build was a local contest for Scale FF models of aircraft involved in World War II’s Battle of Midway. During the battle, a group of B-26 bombers made torpedo runs at the Japanese fleet. There on Dave’s shelf was just the thing—a Dumas kit of the Flying Prostitute, so nicknamed because the wings were so small it “had no visible means of support.”

Dave reports that the kit’s engineering was top-notch and the fit of the laser-cut parts was excellent. Small alterations were made by lightening and simplifying the tail and moving the rubber pegs back to the ends of the nacelles.

Dave also built stronger, simpler thrust-bearing mounts inside the plastic cowls. Six-inch Peck propellers were installed with extra-heavy shafts in nylon Peck bearings. A magnet in each cowl held things in place.

The included domestic tissue was not the correct color, but Dave found it easy to handle, going around the compound curves nicely. CA was used for the structure and a glue stick was used to apply the tissue. Dave employed colored felt pens to simulate the canopy bracing.

Building speed mattered, because the model was only started the morning before the contest! This build took 12 hours from start to test glide. The finish was Blair Gloss Spray Clear (available at art stores) after lightly water shrinking the tissue. Dave used a bare minimum of water spray to avoid warped surfaces. When the tissue was barely taut, he hit it with the finish spray.

The decals were modified to represent the war markings. Dave drew a red center in the star and cut off the side wings of the insignia. Presto!

With two loops of 1/8-inch Tan Super Sport Rubber in each nacelle, the model weighed 3 ounces. Amazingly, it had a floating glide and test flights showed perfect balance and trim straight from the box. After adding some downthrust, the Dumas B-26 had a steady, stable flight pattern with gentle landings.

The highlight of the morning was a flight in which one motor peg came loose. The motor, cowling, and propeller were ejected from the nacelle, but the airplane kept going on one propeller! Dave's friends were howling with laughter and shouting about how everyone knows that a Marauder is dangerous with an engine "out."

Dave didn't win the contest, but finished fourth out of nine. The satisfaction of successfully flying such an unusual airplane was enough of a prize.

Dave added a few words about the Grassy Knoll flying site, where the contest was held:

"The Grassy Knoll FF field is a small open area at Woodley Park, located in Los Angeles. It is bounded by trees, a bus way, and a lake, but by golly it's ours and we have great fun there. The lack of restroom and picnic facilities makes it less popular with families and better for our models.

"The Black Sheep Squadron runs unique local contests there, since AMA events require a larger area. We have learned to compensate for the small space with a 'Must Stay on the Field' rule, which states that flights which go OOS [out of sight] or land beyond the boundaries don't count. Pilots can use a DT to save the model, but if it pops, then the flight time is invalid.

"With this rule, we have found that it is fair to mix power types. Many of our contests allow Rubber, electric, and CO2 to compete together. It takes skill and luck to put up a flight that is long enough to win but short enough to land back on the field.

"We have offered meets for kits from various makers (Dumas, Comet, Diels, etc.) as well as events like Any Printwood Scale Kit and Any Bill Hannan Design. A favorite is Guillow's 500 series. Those difficult little planes can really fly when an expert works them over!

"As you might imagine, the competitive urge sometimes gets overtaken by camaraderie and enjoyment of miniature flight. A contestant might completely forget about [his or her] own model while helping with a competitor's troublesome plane. Sportsmanship like that is rare and precious!"

Contact Dave at [email protected] to join the fun. Check out his column every month in Model Aviation. You can see the maiden flight of the B-26 on YouTube at the link listed in "Sources."

American Junior Classics

When I was a kid, the quickest way to get a model into the air was to buy an American Junior (AJ) Aircraft 74 glider for a dime. If I was really well off and had 50¢, I could buy an AJ Hornet or an Army Interceptor folding-wing glider. These models could fly well and were an important part of the history of this hobby.

They are available again. Check out the American Junior Classics website, listed in "Sources."

Zephyr Model Motors

Email Jim Sprenger at Zephyr for FF supplies including Tomy DT timers, compressed-air motors, simple torque front ends, and other goodies.

Skylake Models

Skylake Models is back—this time with lightweight, laser-cut balsa rather than the original router-cut, harder balsa. There is a nice assortment of designs with wingspans ranging from 16 to 24 inches. These are short kits. Stripwood is not included, but there are canopies where appropriate, and files for printing the color scheme on tissue are included.

Guillow's Challenge

The 2013 Guillow's Challenge in the Yahoo Groups will be a One Design challenge for the new Guillow's kit #703—the Edge 540—to be flown FF with rubber, CO2, or electric power.

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