RADIO CONTROL AEROBATICS
Eric Henderson
303 Shady Ln., Marlton, NJ 08053 E-mail: [email protected]
The question of having product reviews in this column came to me recently in an e-mail. I am always interested in what you all would like to see in this column. A product review is popular with most readers. It requires a different approach, such as taking photographs of the building process as you complete the model. In this column it is not viable to do justice to a product or products and still have any room left.
My basic plan is to review how well an airplane flies the current AMA Pattern schedules. What was brought to my attention was the need to include much more detail when writing about a particular airplane. I can relate to that because I, too, like to know things such as engine information, radio and servos used, etc., so thank you for the request and I'll endeavor to provide as much detail as I can in the future.
Product News
The O.S. 1.60 FX will soon have a competitor, which is being produced by Webra and imported by Horizon Hobby. The Webra 1.60 will have a rear exhaust, an integral pump, and be close in weight to the current 1.45. This should give a welcome boost to the vertical performance needs of the newer wide-body airplanes.
Piedmont Models has been busy working on a second version of its popular (and sold-out) Focus. Although the Focus II is similar in appearance to the original Focus (several parts are plug-compatible), there were enough changes to require a redesign from the ground up. The fin and rudder are taller and wider. Now there is a welcome top access via a removable canopy. Less obvious is a new and different internal structure.
During the lunch breaks at last year's Tournament of Champions, the Hacker team gave several demonstrations of electric-powered airplanes that were fully Pattern-capable. Just as the auto industry is expanding its interests into the field of electric people-movers, one day electrics may be all that we fly. If that is the case, the future does not look that bad.
Electric Pattern Model
The pesky white stuff that keeps falling from the sky has prevented the testing of a slightly modified Diablo. The Diablo is one of a family of electric airplanes imported by Esprit Model of Massachusetts. It is a 3-D, high-performance model that uses a Hacker B50 9XL brushless motor with 20 sub-C cells as a power source. Ni-Cd packs will provide a more immediate dazzle in performance, but 20 NiMH 3000 mAh cells will give longer duration. For more info, e-mail prop.rc@verizon or visit the website at www.espritmodel.com.
So what does it take to get a viable electric Pattern model in the air? "This is not your father's park flyer," so everything had to be purchased from scratch. The people at Esprit Model were helpful, and the order was placed to basically equal the owner's model. (This airplane has a fiberglass fuselage, hence the FG designation.)
The airplane was modified slightly. Who can build an Almost-Ready-to-Fly these days without making some changes? In this case the big change was to double the canopy for a more Pattern-current design. The wing-dowel antirotation pin was replaced by Gator wing adjusters. This allows fine-tuning during flight testing. The Hacker motor and the huge air duct direct to the electric "fuel cell," a.k.a. a 20-cell Ni-Cd or NiMH sub-C pack.
- Diablo Top FG: $289
- Hacker B50 9XL with 5.2:1 gearbox: $309
- Hacker Master 99-3P Opto speed controller: $239
- Ultimate Battery Eliminator Circuit (BEC): $30
- Battery pack — 20 cells Ni-Cd: $115
- Motor mount: $25.25
- Heat sink: $19
- Deans gold connectors: $3
- Spinner 42/6mm: $25
- Prop APC-E 16 x 10: $16
Radio Equipment and Features
All of these new and old JR radios are still Pattern-compatible, depending on your needs. There is a whole range of functionality between these radios. How much of it do you really need? A low-end radio such as the JR 642 (there are more recent equivalents) has all of the functions you need and a few more.
Once you get past the basic needs, you get into what is nice to have. The ability to set the endpoints of servo throws is handy once the base level of mechanical settings has been made. All of the modern radios have dual rates and exponential for flight tuning.
In JR terms, the 388, the 8103, the newer 374 and old 347, the top-of-the-line 10SXII, and the most recent 10X do the basics, so why would you want more? It comes back to the ease with which you can change things to suit your needs and improve the airplane in the air.
Then you get into what you must have in a radio. I find throttle-curve adjustments most useful so that I can set the power to where I want it on the throttle stick.
A big feature is the ability to program in the correct amount of elevator and aileron correction in knife-edge flight. The high-end radios have this as a listed function. It can be done with a JR 8103, but it takes some free-mix programming. When a model pulls to the canopy in a down-line, a neat trick is to mix a tiny percentage of down-trim at low throttle.
There are some advantages to the higher-end radios, but just fly with what you know well and practice the schedules until you need the features. You'll know when you need to upgrade; it will be the aforementioned human desire for more or you are simply ready for more features!
Fail-safe and PCM
One feature that is an absolute must for me is PCM because it allows you to program the default settings of the airplane if you get radio interference, lose a crystal, etc., in the air or on the ground.
Many people confuse previous-position servo lock with fail-safe programming options. My standard fail-safe settings are: throttle to idle, all controls to neutral except the elevator, which is given approximately 5° of up. I get a warning in the air if the throttle cuts back, and a slight bump in the flight path that tells me it is time to land!
The retracts, if used, are left in hold. This is because if the interference is in the pits and the engine is running, you don't want the wheels to retract. Similarly, if the airplane is in the air, I don't want the wheels to come down and rip out the gear mechanisms in a rough "free-flight" landing.
Also with PCM you usually get a receiver-battery-low warning. This is a big plus that also tells you to land immediately. All airplanes become expensive and can be dangerous. PCM fail-safe can save injury and many forms of cost.
Technology does change how you do things. A "fancy" radio gives you flexibility that you did not have before. Initially a computer radio can be more inhibiting because it is new to the user and can be harder to use at first.
Voice Recognition
In a similar vein, this column was not typed this time; it was "talked." I used voice-recognition software. It needed to learn how I speak, and the room had to be cleared of background noises (kids, etc.). The noise from our heating system didn't help either. It took me three times as long to do the column this way, but now the computer understands an Anglo-Scottish-Boston-New Jersey-English accent! My finger pads don't hurt, as they usually do, and the ideas flowed much easier.
So until we "talk" again, keep flying smooth!
MA
Transcribed from original scans by AI. Minor OCR errors may remain.
