Control Line
Racing
John Ballard
The contest season in the Midwest area is in full swing. The first major Midwestern Regional was held outside Chicago in Sugar Grove, IL. The typical racing events—Rat, Scale, Slow Rat—had a minimum of 12 to 15 entries in each event.
Over the relatively mild winter, several competitors had certainly done their homework. Larry Dziak showed up with a new, heavily modified Nelson "long stack" .15 which ran 14.5 to 14.9 in traffic. The winning time in Scale was 5:50, and second place was 6:01, which made for some excellent racing.
Rat Race was a mixed bag, with several competitors trying new AAC piston-and-liner setups with the high-compression Nelson "funny" head that uses the one-piece Nelson plug. The Nelson plug seems quite satisfactory in almost all racing applications as long as proper head clearance is maintained.
Rat Race times were nothing to write home about. Several teams were having warm-up problems with the AAC engines, since the temperature was approximately 45°F with a stiff wind (very unusual for Labor Day weekend).
Most Rat Race pits have now moved to two-man operation: one person applies the glow-plug lead connection and starts the engine, while the other holds the plane and refuels. It appears much easier for the pit man to do the filling as well as opening the fuel shutoff, so there isn't any miscommunication or a flooded engine. The other person's responsibility is merely attaching the battery and starting the engine. The man doing the filling also holds the aircraft.
Slow Rat showed a variety of competitors sporting the new Nelson Super Tigre X-35, which runs very well. I believe one of these engines will be a dominant force at the Nationals, since they seem to outperform almost any K&B or OS presently in existence. Slow Rat times all averaged under six minutes, which was good for the first minor event of the '87 Midwest season.
Engine modification to the K&B .15
I am enclosing some photos of modifications to the K&B .15 which definitely improve the ground rpm of the engine and the resulting airspeed. In the photograph, a stock crank is on the left, and the crank on the right has not only been enlarged but extra material has been removed from the shaft area. In addition, the venturi has been enlarged by about .015 in.
The second photograph shows the enlarged venturi as well as a rear view of the crank; you can see the enlarged hole and the extra material removed near the timing area. These particular cranks close around 60° after top dead center (ATDC). Ron Young's Performance Engines will rework these cranks for you, or you can make the modification yourself. Ron indicates that the enlarged crankshaft on the K&B/OS .15 will flow approximately 30% more air through the engine with a minimum 500 rpm gain on the test stand.
Racing tank refueling procedures
Several competitors have written asking how to prevent damage to the fuel tank from the fill tube when, during a hasty pit stop, the tube is occasionally pushed down into the quick-fill too far and rams a hole in the bottom of the tank.
Ron Esman from the Texas racing contingent found that soldering a small ring onto the neck of the fuel filler prevents the fill tube from going too far into the tank. The ring also prevents fuel from squirting back into the pit man's face, deflecting the spray to either side of the aircraft. The ring can easily be fabricated from a large washer and soldered in place after measuring the length of the tube as it enters the tank.
Mouse Racing
Al Lidberg (Tempe, AZ) has sent plans for his Annie Mouse Racer. The basic aircraft flies very well and has been very successful in local competition in his area. I am including the plan in this month's column. For further information, write Al Lidberg, 614 W. Fordham, Tempe, AZ 85283.
St. Louis alive and well
I just talked to Gary Frost from the St. Louis area, and he indicated that both the flying field and club are in excellent health. Gary is planning an early October contest for '87, so those who asked what happened to St. Louis will understand that the contest schedule is once again reinstated there.
The major problem with the Buder Park flying site in last summer's contest schedule was the interruption when the park had to be used for horse shows instead of model airplanes. Gary assures me this has been rectified for 1987, so this fine Midwest site should again be the scene of a fine annual meet.
AMA records for Racing
I received several requests mentioning Racing events being included in AMA national records. As you talk to your AMA district representatives (both VP and CL Contest Board), please mention that the racing contingent would like to have AMA records for the racing events. If our voice is heard, something should be done.
F2C Team Racer drawings
I have had over a dozen requests for the six sets of plans for the Russian TRs. I have sent copies to everyone who requested them. If anyone else missed my column, I still have several copies left and will be happy to forward them.
As always, your comments and photographs are appreciated.
John C. Ballard 10102 Kimblewick Dr. Louisville, KY 40223
Transcribed from original scans by AI. Minor OCR errors may remain.
