I got my Balsa USA 1/3 scale Ercoupe repaired and ready for test on the Wednesday before the meet, which was scheduled for Friday thru Sunday, April 13-15. Dale Yaney checked it out, and I got some stick time, but Dale recommended adding a servo-operated kill switch, as full closure of the Zenoah G62 throttle still allowed the engine to tick over. I had already replaced the original manual kill switch with a more easily accessible, larger one. It was DPDT, so I wired both poles together for better reliability (like they do on the switches that come with our RC gear.)

Dale also suggested some more nose ballast, since the plane was flying somewhat tail-heavy, even though it balanced on the point shown on the Balsa USA plans. I had removed the 8 oz. spinner flywheel used with the G45, since the G62 is about 10 oz. heavier than the G45. Dale suggested putting it back. We also discussed using a bigger propeller to cut the RPM, thus reducing the dB level below the measured 103 dB.

Another modification needed was to pin the spinner back plate and prop to the G62 prop drive hub, which would make it much easier to tighten the prop bolt, which threads into the drive hub.

That night, I mounted a servo on a plywood plate on the firewall, along with a small roller-lever micro switch obtained from Radio Shack. An arm on the servo output shaft was adjusted to close the normally open switch when a momentary, spring loaded switch (switch "F") on the transmitter was operated. I used the retract gear channel on the Futaba 9CAP PCM transmitter for this servo. I wired the micro switch in parallel with the manual kill switch, so that closing either switch would short the ignition primary, thus killing the engine.

All the 9 sockets in my 9 channel PCM receiver were now full! Hard to believe with a simple, 4-control airplane like the Ercoupe, with no flaps, retracts or rotating gun turrets. The sockets used were: the usual 4 channels plus the battery socket; an unused channel socket for the second battery, the flap channel socket for the second aileron servo; another unused socket for the nose gear servo, and now the kill switch servo in the last unused socket.

I had to remove the nose gear and the front floor carpeting to be able to fish the leads from the kill servo through the firewall back to the receiver, which is under the pilot’s seat. A total of five extensions were now running under that carpet: 3 servo leads and 2 battery leads. (The two 6-volt, 1500mAH, NiMH receiver packs are located in front of the fire wall.)

All this took time, so at 1:30 AM I decided to install the prop and flywheel the next morning, so we could fly the plane again the next day out at the Hemet field. Bad decision! The next morning, Murphy’s Law was in full swing. The 10mm prop bolt had a much larger hex head than the SAE bolt used on the G45. The flywheel design required the 10mm wrench socket to fit down into a recess in the front of the brass flywheel, but the recess was too small in diameter. Also, the prop bolt was too long; appearing to bottom out in the hub, so a spacer washer would be needed.

In any case, it was all made moot by the wind at the Hemet field, which required a 30 degree lean just to remain standing. So Dale, Don Lien and I all went over to Dale’s house to fix some of the problems. Dale used his lathe to machine the recess in the flywheel to clear the socket. He also drilled the spinner back plate and props to match the two holes in the prop drive hub. He then installed two roll pins in the hub to pin everything together.

It turned out that the spacer washer was not needed. The actual problem was distorted front threads in the hub, from over-tightening of too-short prop bolts. This was fixed by force threading the bolt all the way down into the hub, where there was actually plenty of thread length. Dale suggested ordering a replacement hub for when these tortured threads eventually fail.

We ran the G62 with a 22-12 Zinger wood prop replacing the 22-10 APC prop. This brought the G62’s top RPM down from 7100 to 6200. Measurements made earlier had shown that the dB level dropped below 100dB at 6400 RPM, so this seemed to be a good fix. By the way, that Zinger prop is made from very hard wood, probably Maple. The prop balanced perfectly right off the shelf at Dynamic Hobbies. It has much more blade area than the APC, which probably helped it to bring the revs and noise down. The RC kill switch worked just fine.

Many thanks are due to Dale and Don for their help. These are a couple of good blokes!

The next day, Friday the thirteenth, was the first day of the Qualifier. I drew registration number 13! But my superstitious nature was calmed by being told that my actual number was 12. (Don’t ask me how come!) It was a day for test flying, registration and static judging.

The wind was down a bit, so I was able to get some stick time. Dale was unable to make it, so Carl Lindou of the Corona club helped me to get the Ercoupe trimmed out after the changes, and he coached me on doing the flight maneuvers. The Ercoupe is a light wing loading aircraft like a Piper Cub, about 34 oz/square ft. In the strong wing, it kited and soared, with poor penetration. Perhaps we should have added about 5 lb. of ballast on the CG, as it flies quite well on floats, where it is indeed 5 lb. heavier.

I had prepared a scale documentation book on Thursday night. (What do you mean "last minute", I didn’t need it until Friday!) It had the required three separate sections, one each for the Outline, Color and Markings, and Workmanship judges used in the Expert and Team categories. It turned out that in the Open category has only one static judge, who does all three functions. I scored 28 out of a possible 30 static judging points, not too shabby for a first try!

Flying is my weak point, and I did not have much time to get used to the Ercoupe. Nevertheless, on Saturday, in a fairly strong, gusty wind, ably coached by Don Lien, I got a 73.5 out of possible 100 points on my first flight. I lost 10 points because the judges did not hear me call the Chandelle maneuver (actually a 180 degree climbing turn), so I had the potential for over 80 points. This was much better than I expected. The wind and I "blew" the second flight, with an aborted touch and go that ended in the grass, so I got only 40 points. The wind also helped me to decide to scrub the third flight on Sunday morning.

But I accomplished my goal, which was to get the experience of a scale qualifier meet. I enjoyed the whole process, despite the foul weather. The Hemet Model Masters were hospitable hosts, and their facility is just great, with a wider runway than ours in Perris. The raffle and food service were first rate, and the meet was well-run by Bill Hart and his friendly Scale Masters crew.

Larry Klingberg and Dan Egelhoff won first place in team scale with Larry’s incredible, 13 ft. wingspan, 51 lb., ½ scale Farman Moustique (mosquito), an ancient French ultra-light monoplane, powered by an experimental 75cc gas engine. Dan was asked if this big kite was hard to fly in the strong, gusty wind. He answered "What wind?"

Pilots who "qualify", (the top 30% of the qualifier scores) in these qualifier meets can enter the big final meet at Hemet in October. There will be another qualifier in August at Sepulveda Basin.

RRCC members seen at the meet included Dave Johnson (who was also a flight judge), Bill Briggs, Bill Kline, Regis Mocniak, Bob Baker, Bob Jones, Paul Jones, Ken Nutt and Roger Russell. Not bad, considering that our Pattern Meet was the same weekend.