Micro-Flying
Dave Robelen Route 4, Box 369, Farmville VA 23901 E-mail: [email protected]
Indoor Radio Control Championships — Lakehurst, NJ (June 21–22, 2003)
Hello, friends. I have more details and information for you regarding the Indoor Radio Control Championships at Lakehurst, New Jersey. The dates will be June 21–22, 2003 (Saturday, Sunday). Because this is a military facility, preregistration is required. No one will be admitted on a "walk-in" basis. Please do not be put off by this sort of security—since September 11, 2001, we all need to be more alert about security issues.
So that you can be better prepared for the competition, I'll go over some of the more significant event rules that might affect your building plans.
General rules and restrictions
- Rules are based on the current AMA rule book with modifications to adapt them to the indoor environment.
- Power systems allowed: electric, CO2, compressed air, or rubber band.
- Maximum model weight: 12 ounces ready for flight (including batteries or other power sources) for Scale events.
- Maximum wing loading in Scale events: 6 ounces per square foot.
- Maneuver descriptions follow the AMA rule book, except distances will be shortened for indoor flying; any distance changes will be announced at the pilots' briefing.
Scale events
#### Fun Scale (AMA event 520)
- Operated in accordance with RC Fun Scale: AMA rule-book event 520.
- Open to models from any source: factory ARFs, team-built, or profile (road-kill style).
- Static scores: 0–5 points. Maximum (5 points) awarded if the modeler shows proof (one 8.5 x 11 sheet or a plastic-model box) that a full-scale airplane of that type existed in those colors/markings. If a black-and-white photo is used, written material must also be included. No proof = no scale points.
- Flight rules follow the rule book with indoor distance modifiers announced at briefing.
#### Sport Scale (AMA event 513)
- Operated in accordance with RC Sport Scale: AMA rule-book event 513.
- Builder-of-the-Model rule: no factory-built or team-built models allowed. Kit-built models (non-ARF) are allowed.
- Static scale judging distance: 10 feet (instead of 15 feet).
- Judging categories:
- Accuracy of outline: 40 points max
- Craftsmanship: 30 points max
- Finish and color-and-markings: 30 points max
- Total scale score: 100 points max
Indoor RC Aerobatics
- Operated similarly to outdoor Pattern events, with exceptions for model requirements and maneuver size.
- AMA Pattern classes and judges' guide apply except for wording related to distances; the event director will announce distances at the pilot meeting.
- Aerobatics models must be battery-powered electric.
- Maximum battery voltage: 9.6 volts nominal.
- No limit on battery type or capacity, but static power limit: 30 watts.
- Model ready-to-fly weight maximum: 6 ounces.
- Event format: rounds, only complete rounds count toward scores.
- Maneuver schedule: Intermediate pattern.
Indoor Pylon Racing
- Battery: Ni-Cd, no more than six cells, capacity ≤ 120 mAh.
- Model weight: no more than 8 ounces ready to fly.
- Motor: no larger than a GWS type 180.
- Models must resemble full-scale racing aircraft (profile fuselages acceptable) and must take off from the floor.
- Wing airfoil: single-surface undercamber type, maximum thickness 8%.
- Each model must display a prominent racing number on the upper left wing panel.
- Course: two pylons set 75 feet apart; pilots judge their own turns.
- Start/finish line: midway between pylons and set 10 feet to one side of the centerline.
- Races run in multiple-model heats from a standing start. Winners based on number of heats won.
- All personnel must stand well to the side of the racecourse while airplanes are flying.
Indoor Cargo
- Objective: lift the most weight with the lightest airplane. Score determined by dividing payload weight into total weight (gross weight/payload); the winning score is the highest weight ratio (gross weight/payload).
- Models must lift off and fly in a circular path that would fit in a standard gymnasium.
- Minimum flight time to receive a score: 100 seconds.
- Models must land successfully without damage to receive a score.
- Cargo model requirements:
- Monoplanes only
- Maximum wingspan: 24 inches
- Fixed landing gear (any number of wheels)
- Power: electric motors no larger than a GWS type 180
- Battery: up to six Ni-Cd cells, capacity ≤ 120 mAh
- Payload may be any material acceptable to the event director or provided by the contestant.
Duration
- Event: 2002–2004 AMA rule-book event 702: RC Duration.
Special award
- A special award will be given to the highest-scoring Sport Scale model weighing less than 1.5 ounces.
- Dynamic Web Enterprises (www.smallrc.com/dwhtml/lemicro.cfm) will provide this award. Thank you, Dan and Joanne Hurd!
Drop me a line for a complete information package and entry form for the Indoor Radio Control Championships.
Jack Dobbins (402 Lotus Ln., Washington, IL 61571; Tel.: 309-745-8543) has come up with another neat handmade Ready-to-Fly model. This time it is the Microbee, designed for those superlight magnetic control systems. Jack sent me one to check out, and the assembly really did go quickly.
Microbee — ready-to-fly notes
- I installed the RFFS-100 control system in my model, with the actuators modified for remote mounting.
- Motor: KP-00 motor that has been regeared for a larger propeller.
- Power: single 170 mAh Lithium-Polymer (Li-Poly) cell.
- Flight characteristics: sturdy, can circle in a 10-foot radius and has a decent glide.
- If you are looking for something to get into the air quickly, give Jack a call. Price was approximately $40.
My micro project — the P-Nut
Since you readers have been quiet since the last column, I will share one of my micro projects. I had been looking for a design to use for experiments with controls, power, and maneuverability. The result is my P-Nut. A three-view is available for those who like more detail. The wire-cut foam wing uses the MA409 airfoil.
Another phase of the project was finding the motor/gears/propeller combination that gave the best performance for both speed and maneuverability. I tried various gears and ultimately settled on a set found in a battery-powered clock that gave an 8:1 ratio. This turns a 5.0 x 4.8 propeller effectively on a single 170 mAh Li-Poly cell. Static thrust of 26 grams does a nice job of hauling the 22-gram P-Nut through the sky.
Actuator modifications for magnetic controls
The next phase involved the actuators for the magnetic control system. I use the RFFS-100 system and like it, but tail-mounted actuators are unreasonable on such small models: they cause CG problems, control interaction, and cosmetic issues.
Using readily available materials, I assembled a remote actuator package that has worked out well. Placing the actuators in front of one another provides:
- excellent magnetic centering,
- no interaction,
- compact mounting.
Construction details:
- The magnet in these actuators is actually two smaller magnets butted together.
- Using a cutoff wheel in a Dremel tool, I carefully ground a shallow groove in the inner face of each magnet.
- I reassembled them with a short length of .016-inch-diameter steel wire in the groove.
- The rest of the parts were cut from .020-inch-thick aluminum roofing flashing.
- Assembly used contact cement and epoxy.
- Total weight gain for the two actuators: 0.4 grams.
Try it—you'll like it.
How about sending me some of what you have been up to? Project pictures, club activities, building tips, etc., are enjoyable. I will be waiting by the mailbox.
MA
Transcribed from original scans by AI. Minor OCR errors may remain.
