Genesee Valley Aero Modelers
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21 Highview Trail Pittsford, NY 14534 Max Sez FUEL ORDER WILL BE PLACED ON MARCH 13th INFORMATION ON PAGE 3 If you are reading this and wondering why I am writing this instead of Jim, it's simply because I made an agreement (Bribe), with him that I would continue doing half of these while Jim did the other half. Oh, the things we must do for our hobbies. As you are reading this, it is now March. You only have one month to go before the April meeting where we all get to see what you have been working on all winter. I know I have my main project done. Yep, that’s right; the Hawker Hurricane is complete except for final balancing. I'll include pictures below. If you are wondering why it does not have camouflage markings on it, when I was starting to build Eric came up with a suggestion of a plane to model it after that was a little bit different. It was the last Hurricane built by Hawker and was appropriately called "The Last of the Many". Hawker retained ownership of the plane and used it for several purposes including racing. I finished the plan with the numbers it used for the King's Cup race at Wolverhampton in England on June 17, 1950. It was flown by Peter Townsend and came in second. The plane still exists today and is owned and flown by the "Battle of Britain Memorial Flight". We have had three indoor meets at the Honeoye High School gym this winter. Things have gone well so far. Only one plane got caught by the netting and one small RC plane found the wall. Jim said he would have his "Jenny" ready to go for the February date but he didn't show up. Maybe he was scared of another dogfight with my German stick plane. Oh, and there was a helicopter that got a mind of its own and beat itself to death… March 18th is our last indoor flying for the year. See you there. Happy landings… Max
At The Field The weather during the month of February has not enticed me to go to the field. I did manage to get to the field a couple of times in January. We had our indoor flying for February on the 18th. The crowd was sparse but we had a good time. Photos from the January session are included. As you will see Lou is still winding his rubber bands or should I say motors. He finally got the desired results and some pretty good flights. The basket ball was not needed as everyone stayed out of the nets aka: traps along the ceiling. Walt attended and Eric gave his rubber powered plane its initial test drive. The plane flew well and Walt considered the flight a success. Walt is feeling good but is still a little sore and tires quite easily. I received a call from the Titusville Terror (Tom Brown) the last part of January. He was up to do some skiing. His luck was running true to form. When he was here we had our heat wave and rain storms. He did get in some skiing and said he would be back to haunt us and pick up after the Sea Gulls the first of May. The "guys" are planning to head out to the WRAMS show again this year so we will probably get an update on all the neat stuff in the April Newsletter. If the weather gives us a break go for it but be careful of the snow snakes. Those of you that like a warmer flying session hang in there it will warm up before too long.
 Calendar of Events March 18 3:00- 5:00 PM Indoor flying. Honeoye Central School Gym. GVAM members and one guest. July Olean July 22, 23 Sky Rovers fly-in Aug.13 (Tentative) GVAM Picnic Aug. 25-27 Heli Jamboree Oct. GVAM Dinner For Sale Two Hitec Focus Four Transmitters: $25 each Three Hitec 555 Receivers: $25 each Contact: Lou Eltscher, 585-244-9297 How Fast is My Airplane Kimberling City MO Don Johnson editor A good radar gun or some type of speed trap is the most accurate way to determine your airplane's speed. To get a fairly good idea of how fast your airplane flies—without any high-tech equipment—is quite easy. All you need to know is the rpm and pitch (in inches) of the propeller. The propeller pitch is the distance the propeller will advance in one revolution. (Technical Editor's note: The pitch is actually slightly less than that, but close enough to use for this purpose.) To find the speed, follow this simple equation: Rpm x pitch x .000947 = speed. The .000947 converts the pitch inches and the revolutions per minute into miles per hour. For example, if your motor has a propeller with a 6-inch pitch that turns at 12,000 rpm, the airplane will probably have a top speed of roughly 68 mph. (12,000 x 6 x .000947 = 68 mph.) If your model is aerodynamically clean, this figure will be close; however, if you have a draggy airplane—such as rigged biplane—you could loose 10% to 20% of your speed. Park Zone Electric Models from Horizon Hobbies From the Tri County RC Club, Butler NJ by Dr. Alexander Szemere, AVP AMA District II John Donnelly, editor Here is some information for all of you who may be worried about the influx of park flyers and their impact on our channels—especially after the holidays. As an aside, almost all of the models sold at toy and department stores operate on the 27 and 49 MHz frequencies—far from our 72 MHz channel frequencies. Horizon Hobbies is marketing a series of electric park-flyer-type models under the brand Park Zone. These models come complete with a radio system installed. Some models in this line operate on 72 MHz. It's possible (expected) that some who purchase these models may be operating them at places other than what we think of as traditional model flying fields. Horizon recognizes this, and in an effort to minimize the potential of radio interference they have limited the channels these models operate on to six: 17, 19, 21, 50, 52, and 54. From The Fuel Fool I will be placing a fuel order on the 13th of March. Contrary to what was in the February Newsletter we will be ordering Kool Power and Omega fuel. We had a much better price from Performance Hobbies that came in after the Newsletter was mailed. Kool Power and Omega fuel is made by Morgan fuel and is a very good fuel. Both fuels have 17% lubrication with Kool Power lubrication being 100% synthetic and Omega lubrication being made up of 30% Castor and 70% synthetic. Two cycle and four cycle are the same price The price per gallon is as follows: 10% Kool Power or Omega $12/Gal. 15% Kool Power or Omega $13/Gal. This includes sale tax and shipping.
Which is Better: PPM vs. PCM by Ed Olszewski Aside from all the other choices when selecting an RC radio system, the terms PPM and PCM comes up. PPM or Pulse Position Modulation is standard FM. The next step up is PCM or Pulse Code Modulation which seems to be shrouded in mysticism. In a nutshell, it is not what frequency each is on, but how they use their frequencies. To demystify PCM somewhat you should understand that there is no range increase with PCM. It is not on some special side band or frequency. It shares the exact same FM frequency everyone else on your channel is using, and is susceptible to the same interference. There is, however, improvement in noise reduction and safe performance while the noise is received. Noise is the undesirable signals on your frequency. They can be caused by anything from sunspots to another transmitter horning in on your frequency. Today's modern radios operate on a narrow band that eliminates most of the random noise. Basically, the PCM radio takes your FM signal and "codes" it digitally (the "C" in PCM). Then the PCM receiver "decodes" the signal to utilize it. Since noise is not a normally recognized code, it is ignored by the PCM receiver, and is not sent as servo instructions. In addition PCM does not transmit position signals for each servo in each transmitter pulse. Rather it transmits movement commands as required, and occasional positions confirmation commands. Short periods of interference will simply leave the servo at its last known position, and not show such radio interference as glitches or fluttering. If your PCM receiver continuously receives interference past the preset time, it then switches into "failsafe mode," and obeys some preset commands you programmed in the receiver. For example, you may set failsafe to throttle down and move all other surfaces to the neutral position. This is great if you are in level flight, but disastrous if you are exiting a loop. If set to continue the last command, it will often keep your model in the loop. Unfortunately, failsafe settings will put your model in a precarious situation you didn't want it locked into. A third level of protection may be obtained by using a pilot assist module in combination with preset positions on the failsafe settings. You can help ensure your model will go to level flight at a slow—but safe—airspeed and hopefully safely ride out the interference. Even though the radio does not glitch, it is not to say the PCM radio was in good contact at all times. If another radio is transmitting on your frequency, it can—and likely will—interfere with your receiver’s ability to receive the proper signal from your transmitter. The CB radio enthusiast in the seventies used to call this being "walked on." PCM will help keep your receiver from acting on a bad signal, but there is nothing it can do if a good signal can not be received over the interference. The logic of PCM is that it is better to momentarily do nothing than act on a bad signal. PCM benefits are purely in precise transmitter/receiver communication. PCM does, unfortunately, have a serious weakness. Even minimal atmospheric or external noise can foul up those wonderful intricate binary numbers beyond any correction. In that case, the receiver is up a creek without a paddle. Think of it as if trying to communicate a grocery list via cell phone in a "one bar" area—some things are not going to make it in the grocery cart. With PCM the main purpose is to hide glitches by not transmitting them to a control surface command. As far as the pilot is concerned, there is only an unnoticeable momentary loss of control. If the radio interference is persistent, the pilot will probably be unaware and may lead to total loss of control sending the airplane either into the wild blue yonder or to the ground. On the other hand, the simple PPM pulses may be corrupted with some information getting through. When things go bad, the choice is between no control (PCM)—and some control (PPM). Most RC pilots would prefer having some control even if erratic. When a model aircraft is suddenly doing the funky chicken, it is normally a signal to land. Most radio interferences are normally small glitches and are recoverable, giving the PPM pilot a chance to land and find the cause of the problem. The bottom line is if you are looking for a bullet-proof radio system to keep your airplane from falling from the sky, it does not exist. A system sporting PCM is an excellent choice for larger acrobatic and 3-D fliers with quick throws, where a small glitch may send it suddenly into the ground. PCM will of course work on smaller, more docile airplanes. These airplanes will benefit less from the added features, and PPM is probably a good bet. Remember there is no substitute for a good battery charge and a range check. If another radio on your frequency is turned on, there is little any radio can do to keep you from being "shot down." Safety in the Workshop It’s winter and the building season is in full swing. Just as the safety coordinator focus on flight safety during the flying season, he should not forget about shop safety during the building season. Below are some general tips to share with your club Keep it Clean Many injuries result from poor housekeeping in the shop. Trips, slips, and falls account for the bulk of these mishaps. Scrap material and wrappings, loose parts, scattered tools and equipment, or oil spills can cause injury. Debris should be swept up and disposed of. Parts should be kept on work benches. Tools should be placed where they cannot fall and cause damage or injury. Oil spills should be covered with absorbent material and cleaned up. Lighting, Heating, and Ventilation
Sources: www.safety-council.org and Microsoft Clipart (image)  G.V.A.M. Newsletter |
