Timers Nightmare (oz205)

About this Plan

Timer's Nightmare. Class A contest free flight model, by Frank Ehling. Pylon layout.

Quote: "A reliable easily-built class A gas model designed to give highest performance by FRANK EHLING

HAVE you ever watched a contestant walk up to the processing table, have his ship checked, be assigned to his timer, and go out to turn in a prize winning flight? Well it is not entirely the contestant that deserves the credit; true, he must build and ship and get it in flying form - but here we have a ship that need only be built, because she will fly by herself with no tricks necessary to obtain good flights. For this reason it is a favorite with all that have seen her perform.

At the first contest, after a number of test hops, the ship was entered for an official flight. There was little time before the meet to install a dethermalizer for bringing the ship down in the required four minutes, so we got the bright idea of camouflaging the ship to make it invisible after about four minutes had elapsed. But we are still being ribbed, for when it made its second flight the recorded time was only thirty-five seconds (the timer's stop-watch stopped); the actual flight time was three minutes, forty seconds.

The second meet in which this ship was entered was a marathon contest. In such contests the builder is under as much strain as the ship, for the fellow that turns in the most flights over a minute is declared the winner. This meet was between the Linden Model Club and the Jersey Air Wheels. The Linden boys won high; with Minnay first with eight, yours truly second with seven and Mush third with five. This shows the ship to be a consistent flier as well as one capable of high time.

It was designed especially for the new rules. The fuselage shape used gives the least drag for the amount of space required to house the coil, condenser, battery box and timer; also it blends well into the pylon which was used to get the wing high and well forward. This is the best way to spell 'stability.' The wing was designed with a thin wing section in order to decrease drag in the climb. The long tail moment arm was used in order to make it hard for the ship to soar in a thermal. The ship was designed with a short landing gear to serve as landing purposes only.

These features put the ship in the high performance class despite the little power. On the wing plan you will notice that there is a section that may be added if a motor with a larger displacement than .097 is used; however, motors over .199 should not be used.

Enough talk, a 'slip of the lip' won't build this ship; so clear the work table and to work. The plans are one-quarter size, so enlarge the plan of the crutch, wing, stabilizer and rudder four times the size shown on the plan. Start by cementing the motor bearers to the crutch and then assemble. The formers are now cut and cemented in place.

The pylon is now made up and cemented in place. Install the ignition and sheet the sides and bottom as shown on the plan. The landing gear is now bent to shape and bolted in place. The tail

rest is cemented in place ; this is used in order to keep the tail from wobbling in flight. Cover and water dope; set aside to dry.

The wing is very simple to construct. Cut the ribs out along with the spars and wing tips and assemble. As the wing section is flat there will he no trouble in construction; after which the wing gussets are added. These are used to main-tain the dihedral in the wing. Add the wing tips and go over the whole wing with sandpaper so the wing will be smooth in order to get the covering on smoothly. It is best to cover the wing with Silkspan and apply it wet to the wing. This is done in order to get the covering on easily.

The stabilizer is then made in the same way except that there is no dihedral. Cover the stabilizer in the same manner and put it aside. to dry with weights to prevent any warps that might occur.

The rudder is then cut out of sheet and sanded to a streamlined section, after which it is cemented to the stabilizer. A former similar to the one that is at the rear of the fuselage is cemented to the front of the rudder. When this is dry the rudder is covered; include this former in the job as that is how the rudder fillet is formed, thus forming the rear section of the fuselage.

The whole model is now given a coat of clear dope. After this dries the sec-ond coat should be applied, but it is best to brush the dope opposite to the first coat, in this way there is less chance to miss any spots. The colored dope can now be applied - this is best done if the dope is thin. After two coats are applied the model can be rubbed down. A good trick is to get a damp cloth and a little Bon Ami and start to go over the whole plane as if it was dirty. In this way the covering will not be cut through in any spot like sandpaper will sometimes do if extreme care is not exercised.

Test flying this ship will need no explanation to talk about; simply glide the ship till a good glide is obtained, add a little negative to the tail if the ship seems nose heavy. Start the motor and set the timer for about five seconds, observe the flight and glide to see that the ship is circling opposite the glide.

This ship, despite its cost, should give you plenty of fine flights as the original is still going strong and the only trouble that was encountered was to recover one section of the wing."

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