RADIO CONTROL HELICOPTERS
Dan Williams, 27 Treeline Dr., Liverpool NY 13090; E-mail: [email protected]
IS WINTER OVER YET?
Since I'm writing this in November, I can only hope that there will be a sufficient number of days (on the weekends, because daylight is in terribly short supply here during the winter months) when the weather breaks enough for us Northerners to get out and get a helicopter fix.
Even though spring has officially sprung, we can get snow up here until May. If it isn't snow, then it's that gray, damp, drizzly weather that keeps us inside, hanging out in the shop, looking for something model-related to do. I don't know about you people, but right about now I'm really looking forward to a whiff of nitromethane.
Every spring I head to an NHRA (National Hot Rod Association) national drag-racing event in Georgia, fly some helicopters with some good friends, and visit my brother. There I usually get more than my share of nitro fumes. Those guys really know how to burn nitro! Burning as much as 90% nitro for a mix, they go through an incredible amount of it. I remember when a nitro manufacturing plant blew up in the 1980s, driving the cost of our nitro-mix model fuels through the roof. I think we were importing nitro from overseas. Guess where it was all going? They burn something like 15 gallons of fuel per run. And you thought your big-block O.S. sucked fuel?
A short time ago I received a packet of information from a model club in Scranton, Pennsylvania, called the Black Sheep Squadron. Steve Kurimchak, the press relations person at the club, sent me a short write-up about the group and pictures of its activities. Steve wrote:
"The Black Sheep Squadron of Northeastern Pennsylvania enjoys helicopter flying year round. Some advantages of winter flying of rotary aircraft are no assembly required in the freezing weather and easy landings and takeoffs from a helipad you can make in the snow with your boots!
"Electrics offer the advantage of using the batteries as hand-warming devices after flying! Indoors helicopters can be flown almost anywhere. And when the sun goes down the lights come out for even more fun!
"The Black Sheep Squadron has a program to teach new pilots basic flying skills, be recognized by the club for their achievement, and be given a pair of cool wings as well! The Solo level teaches mastery of the hover and maintenance skills, the Intermediate level adds forward flight skills, and the Advanced level tops it off with basic aerobatics."
Steve included some pictures of the club's activities on and off the field, and I've included a few in the column. It sounds as if this group has successfully integrated a helicopter training program into the club. I know that many helicopter clubs support the teaching of newbies, but I don't know of too many that have a formal program for teaching helicopter flying skills. Congratulations to you and your club, Steve!
I asked for any club-related activities that you would like to see published in the column. This is your column too, not just mine. I like nothing more than putting something such as this in my writings. If it will inspire a club to take on a particular aspect of the hobby, such as a training school, then it's worth my time to include it. I think readers also enjoy seeing what else is going on out there in the sometimes-lonely hobby of flying model helicopters. If you have anything you'd like to see published in the column, send me a short write-up and a few photos.
If you're looking for a way to increase your club's size, there's no better way than to introduce a formal flight-training program. You will fill the ranks faster than you can believe with new, enthusiastic members. Some of them will want to repay the club for the training by becoming instructors themselves. My fixed-wing club has done this for roughly 13 years, and it does indeed sustain the membership.
Hirobo recently introduced the latest incarnation of its popular Sceadu, called the Evolution (EVO). It is available in 30- and 50-size versions. The following details are from a press release. The EVO is not an all-new helicopter, in that many parts from the original Sceadu can be used in it. All EVO parts will fit the original Sceadu.
The Sceadu Evolution uses a new plastic formula for strength and longevity. A new, larger fuel tank (from 350cc to 480cc) has been incorporated for thirsty 50-size engines. The cooling fan has also been increased in size.
The rotor head has a new design feature that allows smooth and stable hovering almost hands-free, as well as the capability to perform aggressive 3-D maneuvers. The overall design is ready for any 50-size helicopter engine. A third bearing block in the engine drivetrain supports the engine's power output without early wear of critical parts.
The 50-size EVO comes with push-pull controls on both cyclics and the collective system, as does the 60-size Freya. The 50-size version also comes with a constant-driven tail rotor system.
For training purposes, the EVO head has a feature called the "Auto Stability" setting, which consists of adding a couple components to settle the machine into a docile, training-mode helicopter.
For the build-up of the kit we enlisted the "novice skills" of a fixed-wing pilot with no helicopter experience. The rest of us could put almost any helicopter together in our sleep, so it's getting harder for us to get a fresh view of the assembly procedure. Bob O'Neil, of the Rochester Aero Modeling Society, was volunteered for this experiment.
It took Bob roughly 30 hours for the build-up, which included the complete helicopter and radio installation. That's not too bad. I remember my first time building up a helicopter; of course, they have improved a bit since then.
During assembly, Bob managed to get the tail-drive assembly upside down and it was not found. It was a direct fault of the manual, but a general poor understanding that sometimes exists when upgrade parts are included with a stock kit. He wasn't sure which way it went in.
Another pitfall for Bob was when he got an extra twist in the tail-drive belt, just for good measure. We didn't catch it in the initial look-over of the completed model. We found it later, after the first flight, when we couldn't track down the source of drag on the head. A few of us have done that at one time or another, but I never have. Yeah, right. It's a typical newbie mistake that we should all be aware of when checking first-time builders' models.
An area of concern for Bob was using Loctite in the vicinity of plastic parts. He and many others have the idea that this adhesive will attack any plastic. According to Loctite representatives, only ABS and styrenic plastics are affected. Almost all plastics used in helicopters are of the nylon family, whether carbon- or fiberglass-reinforced or Delrin. We had to go through and add Loctite to some critical areas before the first flight and some after.
In all, Bob did a good job for a first-time helicopter builder. I'm sure he'll get more practice as the re-kitting and rebuilding commences.
We liked the EVO's driven tail assembly. Although a beginner doesn't really need it, those who want to start 'nutzing' around with pirouetting and backward autorotations can use this machine to their heart's content.
The molded battery box is a nice addition to any kit. It helps protect the electronics from beginners' knocks and tip-overs, up to the full-bore driven-into-the-ground 3-D maneuver. For the gyro, there's a choice of where to mount the sensor. There is a plate in the front and in the rear of the model.
Hirobo molded a 'keyhole' fuel-line pinch-off right into the side frame. This is really cool. Just pass the fuel line through the hole and forget about hemostats or IV clamps to cut off the fuel to the engine. That was a nice touch.
A 50 muffler was included in the upgrade kit. This is not the case with later kits. I'll have more about this later.
The control system is very Bergen/Intrepid in style, as in the push-pull and collective arrangement. This system has always been a favorite in a non-CCPM (Cyclic Collective Pitch Mixing) helicopter. It takes the slop out of one-sided servo actuation and allows the servo to use all the power for the system. Correctly applied during design, this system can be virtually free of control interaction.
Now for some of the things we didn't like.
The many Phillips-head self-tapping screws used in assembly of the frames were reminiscent of my Concept days. They don't last very long, especially if they are overtightened. They can strip out the hole fast. It's not a showstopper, but for longevity's sake, we prefer something more robust. We replaced them with Allen-head bolts and lock nuts.
We also dropped the boom supports down to the lower holes for a better mechanical advantage. It wouldn't be a big deal for strictly a trainer, but this is a must for 3-D and heading-hold gyros. We learned this from Curtis Youngblood's visit last summer. That was the first thing he went for when evaluating a helicopter's airworthiness. The tighter the tail support, the higher the gyro gain can be for the wilder maneuvers.
The other thing we didn't care for, as I mentioned earlier, was the way the upgrade parts were included with the stock parts. This happens often when there's an upgrade available. Confusion ensues for newer builders when they are faced with which parts to use in the build process.
I spoke with Jeff Green of Model Rectifier Corporation, which imports Hirobo products. The EVO kits were initially released by MRC—not Hirobo. If you have one of these kits, see the addendum from MRC about the upgrades. In the later kits the upgrades are fully integrated into the parts packages and the instructions. Jeff apologized for any confusion, but he wanted to get the EVO out as early as possible. Stuff happens sometimes.
In stock setup and form, using an O.S. .50 engine with the provided muffler, the machine has a soft feel and a slower roll rate. We used some FunKey blades and the stock paddles for the head. In this form it will loop and roll, but it does not have the agility of a machine that is tweaked out for rocking and rolling.
We had the head set up in "Auto Stability" mode, which probably accounted for the lack of crisp response. It was a nice, solid 50-size machine to fly. We haven't had a great deal of time on this machine yet. We may try experimenting with the other setup mode or different paddles to see what will happen.
I had the recent good fortune to fly with Jeff. He used a stock machine with an O.S. .50 and a FunTech muffler, and it looked as though it was taking everything he would put to it. Jeff wasn't gentle with the model; rolling tailslides, death spirals, and climbing pirouetting spirals were in his repertoire that day. The head was set up in an "Auto Stability" mode with the brass weight removed. He pushed the machine hard.
For more information, contact MRC at www.modelrectifier.com.
That's it for this month. May your takeoffs not exceed your landings. See you next month. MA
Transcribed from original scans by AI. Minor OCR errors may remain.
