Radio Control: Helicopters
Dave Chesney
This month, we'd like to give you a first-hand look at the new Gorham Model Products Cricket helicopter. It is the first of the "new wave" of small choppers — sized for a .25 engine. Ken Kiel of Sparta, WI was persuaded to share his experience with this new machine with us. Ken's report follows.
Ken Kiel — Cricket report
On a Saturday morning I arose early and drove to Galesville, WI where RC Unlimited had my new Cricket in. I think I woke up Captain Dan. He handed me a small box and, in return, requested a large fee. Having a bit of traveling to do that day, I quickly paid and departed on my way. That evening I unpacked the Cricket and, being undecided how to prepare it, I assembled it temporarily to see what it looked like. This took about three hours, not checking alignment and so on. Seeing it on the table, there was only one conclusion: it had to be in Army colors with a Kavan pilot in it and look like a little attack helicopter. I took it to a fly-in the next day, just to show it off.
Sunday evening I disassembled it and started painting it. Monday evening I started assembling, following Gorham's instructions closely. These were very good, and were made even better with the additional sheets detailing some of the modifications which have been added since they began manufacturing the kit. My Cricket is the 457th produced. I put in an OS Max 25 FSR for power and a Litco micro-receiver and micro-servos to operate the thing.
Everything in the control system has to be free and really easy to operate with this setup, so that the servos will have enough power to operate them.
At first, when I tried to fly it, all it wanted to do was back up on me. Finally I found out that my flybar was too snug. I loosened that, and away it went!
One thing about the Cricket is that occasionally the tail rotor will strike obstacles like dirt, tall grass, etc. It will simply unwind off the shaft and has done no damage either to the tail or to the gear. Possibly the simplest machine I have ever seen. The motor sets comfortably facing back; start with a conventional starter — the head sticks out the side and it needs a good heat sink since the Cricket has no cooling fan.
I've heard rumors that the bearing on the drive shaft will heat and stick to the drive blades. There is no clutch; if you have a problem, put a very thin washer between the clutch and the drive shaft for clearance. The belt drive should be left with about 5/8-in. slack, as shows up well in the photos. Tail rotors feed through the drive shaft right off the top. The belt drive does not align the shaft very carefully; if there is a little bend it possibly will break. Again, I have had no trouble. A suggested fix is to add a section of small flexible drive-cable guide over the support shaft — it will never break. The point-up main shaft is well designed.
One small mod: the forward/aft rocker arms hit the swash-plate holder — cut a small angled aluminum T-arm to get a bit more throw. Also, I had a lot of trouble getting the main rotor blades adjusted to the proper pitch. I took an old pair of Heliboy blade holders, rounded the end, flattened and sawed off the last bolt holes. The Heliboy parts fit the Cricket blade holders exactly — same size — and allow pitch adjustment with two wrenches.
Without change I found that by adding a couple of ounces to the front of the Cricket I could get balance, maybe because the micro-pack I have is lighter than the installations Gorham used. I have flown the Cricket quite a bit the last month. I did a loop the first time; I won't talk about the second loop now. The Cricket repaired easily and I am just getting familiar with the setup. I mixed the tail rotor trim to see how it would work. It's set up stable in hover; in forward flight the tail will track a little to the left of the body. Add a touch of trim and a fixed tail surface will hold it right. I should already have the new acrobatic head ordered — it's out yet; hope to get it soon — it should make the Cricket a really super machine.
As for flying, the Cricket seems well-behaved. It is a little machine, quite reasonable to repair, align and maintain. With a little forward trim cranked it will be almost hands-off in hover and it responds right away when given a command. Fast flight is harder to control, but it may be one of the best machines available for the money, especially for the average flier who just wants to learn to fly a copter and buzz around the sky. It can be flown close-in — schoolyard flying — and is quite fuel efficient.
I would like, at this time, to thank Gorham Model Products for coming up with the Cricket. It is definitely a very fine flying machine, and I think it will make both a very good trainer for beginners and a fine proficiency model for the more experienced fliers.
Next month we'll be back to helicopter systems — with a specific look at shortening the Heliboy control rotor.
Dave Chesney Rt. 9, Box 621A Greensboro, NC 27409
Transcribed from original scans by AI. Minor OCR errors may remain.
