We all know that the claimed “C” numbers of LiPo batteries are fallacious. Some brand are more outrageously exaggerated than others. If your charger can measure the cell IR (Internal Resistance) of you can use this online tool to calculate the REAL “C” value – as well as establish the maximum amp draw your batteries can deliver without damage. (Realize that the IR measurements from chargers are not as accurate as from higher end dedicated meters)In the example below a brand new “35C” battery is revealed to have an actual C value of 18.35. This is done by simply inputting the capacity, the IR of the highest cell and the cell count. Use the link below to use the calculator. https://www.soko-heli-tools.com/calculators“
Wire Connectors vs Soldering
Did you know that properly crimped connectors are less prone to failure than soldered. JST-SH crimping tool (and reading glasses) will allow you to customize the length of servo wires or make single gender wires. The connectors are actually called Dupont connectors. Did I mention reading glasses are helpful While I’m not promoting the Hobbyking connection crimper – they do have an excellent video on the process. https://youtu.be/X0jgGeugXX8
To get off the ground, your R/C airplane or helicopter needs power — whether from an electric motor, a gasoline engine, or most frequently, a glow engine. The size and type of engine will be determined by the size and type of aircraft. Helicopter engines are designed specifically for the space, weight and power requirements of R/C helicopters…airplane engines are engineered for the same criteria, applied to fixed-wing aircraft.
Choosing your aircraft engine
Many R/C planes as well as helicopters have names that contain a number. That number designates the class of engine which is required. Planes that are “40 size” use a .40-class engine, which includes those in the .40 to .53 cubic inch displacement range (for your convenience, all of Tower Hobbies’ product descriptions list the appropriate engine range in full).
Too much power is not a plus!
R/C trainer planes are usually designed for .40-class 2-stroke glow engines, and often fly best with engines from the lower end of their recommended ranges — a .40 cubic inch engine will work fine with a “40 size” trainer. The plane’s requirements might indicate that a .46 or even larger size is acceptable. But in this case, bigger is not necessarily better — the larger engines will require more throttle control from you. And you have enough other things to learn!
By contrast, seasoned pilots often gravitate toward the middle or higher end of the engine displacement ranges recommended for their “sport planes.” That’s because the added power gives their aerobatic maneuvers more oomph…and the pilots themselves have the experience to handle it.
What to consider?
2-Stroke or 4-Stroke?
Refer to our engine basic section for a comparison of these engine types. In brief, 2-strokes are cheaper and easier to operate, but 4-strokes offer better fuel economy and a more realistic sound.
Ball Bearings or Bushings?
Some aircraft engines feature crankshafts that are supported by bushings…others use ball bearings instead. If low cost is your priority, go with the bushing-equipped engine. If you’re willing to pay a little more for an engine that will run smoother and last longer, look for an engine with ball bearings.
Ringed or ABC?
An engine’s piston and cylinder assembly can have either of these types of construction.
Ringed engines use an aluminum or iron piston that moves inside an iron sleeve. The piston is surrounded by a ring that provides compression. Advantages include economy, easy starts and good power. Disadvantages? The possible need for a longer break-in period, and greater susceptibility to damage if your carburetor is not adjusted properly.
ABC engines use an aluminum piston that moves inside a chrome-plated brass sleeve. The fit of the piston and cylinder is perfected at the factory to provide excellent compression. Advantages include easy starts, shorter break-in, greater power, longer life and less susceptibility to damage from improper carburetor settings. Disadvantages? Higher price — and costlier repair, if the piston/cylinder assembly ever needs to be replaced.
What accessories will I need?
For whatever aircraft engine that you order (or is included with your model), check the “Accessories Needed” link on its towerhobbies.com product page. There, you can quickly find out what additional items are required to run it.
All glow engines will require glow fuel, fuel line, spare glow plugs and perhaps a muffler or tuned pipe. With airplane engines, you’ll also need propellers — and possibly an engine mount and spinner.
Propellers come in many different sizes and shapes. Your engine’s instructions will recommend appropriate sizes (as will the Accessories Needed link on towerhobbies.com for that particular engine). Sizes are given in two numbers (6 x 3, 10 x 6, etc.). The first number is the diameter of the prop in inches. The second number is the pitch, or twist, of the propeller. The larger the number, the greater the pitch — a prop with a pitch of 4 will move forward 4 inches during one revolution.
Spinners are the cones you see on the “nose” of model airplanes. Though they offer some aerodynamic benefits, they’re primarily cosmetic. Spinners are available in white, black, and some colors, as well as with a polished aluminum finish. Choose whatever makes your model look best!
If your airplane kit is not equipped with an engine mount, perhaps the simplest solution to mounting is a Great Planes Adjustable Engine Mount. Their design offers enough flexibility for you to get an exact fit for almost any 2- or 4-stroke glow engine. Many engine manufacturers also offer mounts that are custom-made for their engines.
Electric models use small motors, powered by battery cells. Those motors should not be confused with glow engines — which are actual internal combustion power plants that form the heart of any “gas” or “nitro” powered R/C model.
Most nitro R/C models use a 2- or 4-stroke glow engine, sized specifically for that model. Typically, they range in displacement from .049 cu. in. to 1.2 cu. in. (80cc to 20cc) — a variety that satisfies virtually any model’s power requirements.
Glow engines cannot be operated with the same gasoline you’d get at a filling station pump. They require a special fuel, called “glow fuel.” It contains methanol as the base, with varying amounts of nitromethane to increase the energy that the fuel can provide. Oil, pre-mixed into the fuel, lubricates and protects your tiny engine as it pounds out amazing power. When you get your new engine, first examine it carefully for any obvious defects. Read the operating instructions closely. If the manufacturer suggests a specific procedure for breaking in the engine, by all means, use it!
Two-Stroke vs. Four-Stroke
You’ll quickly notice that many R/C models give you the option of installing a 2-stroke OR a 4-stroke glow engine. How do you know which is best?
Two-Stroke simply means that the engine “fires” (ignites the fuel in its combustion chamber) with every revolution of the piston. Generally, they’re a good place for new nitro modelers to start. Two-strokes are easier to operate, less vulnerable to problems if misused, and deliver more power for their size and weight.
Four-Stroke engines fire once with every two revolutions. They consume less fuel, sound more realistic, and provide more torque — but cost more, are harder to adjust and require more maintenance.
How does a glow engine work?
Most glow engines have a simple ignition system that uses a glow plug rather than a spark plug — so there’s no coil, magneto or points. The glow plug is heated by a battery-operated glow starter; meanwhile, the modeler uses a recoil starter, Electric 12V Starter or Starter Box to turn over the engine. When fuel enters the combustion chamber, it’s ignited by the heated glow plug — and with that, the engine springs to life, instantly gaining the momentum to continue running after all the starter accessories are removed.
The engine’s carburetor supplies the fuel and air needed for combustion. It has several adjustments. A rotating throttle arm controls the AMOUNT of fuel and air that enters the combustion chamber. The high-speed needle valve controls the MIX or proportions of fuel vs. air at mid- to high-speeds. The idle mixture screw is similar to the high-speed needle valve, except that it controls the mix of fuel and air when the engine is only idling. When you’ve adjusted the high-speed and idle mixtures properly, your engine should operate smooth and steady throughout its speed range.
Tower Hobbies has many books available with helpful information about glow engine operation and maintenance.
How do I care for a glow engine?
If you take good care of your engine from day one, it will reward you with a long life of optimum performance. Proper maintenance is not difficult. Some of the best tips include:
Use a brand-name fuel that contains at least the amount of oil recommended by the engine manufacturer.
Use fuel with the proper percentage of nitromethane, as recommended by the engine manufacturer.
Other types of R/C engines
Models designed for first-time R/C hobbyists will not require any power plant other than an electric motor or 2- or 4-stroke glow engine. Other types of engines are used at more advanced levels of the hobby, however. For example, some R/C jets are powered by ducted fan engines, and some large-scale aircraft use genuine gasoline engines similar to those found in chainsaws and “weedeater” lawn tools.
What accessories will I need?
For whatever engine that you order (or is included with your model), check the “Accessories Needed” link on its towerhobbies.com product page. There, you can quickly find out what additional items are required to run it.
All glow engines will require glow fuel, fuel line and spare glow plugs. You may also need a muffler or tuned pipe. Most model airplanes require an engine mount, which may or may not be included with the kit. All model airplanes and many boats will also require propeller(s).
It’s been a fabulous month for flying aircraft – especially for Febru- ary. By my observation, there has been someone flying at the field at least 21 days this month.
It’s also been an interesting month as far as the FAA impinging on our hobby goes. The RID NPRM (Notice of Proposed Rule Making) has achieved over 30,000 comments on the online National Regis- try. There will likely be somewhere in the neighborhood of 5,000 additional comments submitted by fax or snail mail. Washington D.C. insiders are astounded at what they consider a very high vol- ume of response. The EAA (Experimental Aircraft Association) and the AOPA (Aircraft Owners and Pilots Association) strongly encour- aged their membership to support the hobbyists in making com- ments to the FAA – and they responded with a clear voice sup- porting us. March 2 is the last day to submit comments. If you would like to add your voice comment HERE.
After March 2 the FAA is required by law to read every comment. Some have suggested this process alone could take as long as two years. Once the comment period is over discussion by the public with the FAA on this matter is over, but it’s not time to relax. Con- gress can still interact with the FAA on this matter so the next phase of the campaign to “save the hobby” will be to carpet bomb congress and senate with well composed letters and try to get them to flying fields to see what the hobby is about. When writing your legislators it’s critically important to make sure you reference your comments are in regard to docket number FAA–2019–1100. I’ve seen several replies from this state and others in which the specific issue was apparently unknown to the legislator and their comments were about completely different NPRM’s or issues.
At the club meeting I addressed the protocol of having a spotter when flying. It’s not critically important to have a spotter if you are the only pilot on the flight line – however if there are three or more pilots on the flight line utilizing spotters is necessary. If two pilots are standing proximal to one another they can communicate without a spotter – but having a spotter for them to share would be better yet. An additional set of eyes coupled with good communication can prevent mishaps and help make a safer and more enjoyable environment.
As a pilot you want to have a spotter you can trust – so (for example) if they tell you that you’re landing to the side of the runway you don’t discard their observation but reevaluate yours. An effective spotter doesn’t chat with or otherwise distract the pilot and stands to the side and just behind the pilot so as not to be seen in their peripheral view. Finally, if you notice that there is a need for a spotter take initiative and approach the pilot and let them know you are approaching as their attention will be on the aircraft and you don’t want to startle them.
My final words on spotting. It’s the law that unmanned air- craft be observed from the pilots location. If the pilot is flying FPV then he/she must (by law) have a spotter proximal to them to observe the aircraft and advise the pilot if the aircraft is leaving the field of view. Beyond visual line of sight (BVLOS) operations without a Part 107 license are both illegal and as such damage caused by BVLOS may be difficult of impossible to cover with insurance.
Fly safe, have fun, and support your club members.
March 2020—FAA RID NPRM and Spotting
An effective spotter:
alerts the pilots to items that may be distracting outside their field of view.
alerts pilot of obstacles in their flight path, including aircraft, birds, etc
Reminds pilot of whatever they request, such as flap position, gear position, disablestabilization, etc.
helps them line up for final approach
Helps with trim switches when requested
helps them when things to awry – such as getting a vector on a downed plane.
We had the monthly meeting Thursday, February 20. About 15 members were present. Scott presented the safety topic about spotters when more than one pilot is flying. It is important and required by our safety standards for this. The spotter makes sure all pilots know others are in the air, alert pilots about landings, takeoffs, and if full scale aircraft approach. Pilots should acknowledge these alerts so everyone knows and understands the field situation. If a pilot doesn’t acknowledge the spotter should verify the message was understood, as some of us are having hearing issues. All of us should review the field safety requirements posted on the board on the shelter. Larry presented the financial report. We have about $3400 in the checking account with all known obligations paid to date. This is adequate to meet current known needs. Bob presented the field conditions. Field is in good shape as a mild winter so far. We are planning a field cleanup day Saturday, March 21. More to come as the day approaches, but mainly for now, clear out tumbleweeds, wash tables, patio, and other areas. The next event is the IMAC, Saturday and Sunday, April 4 and 5. This is a fundraising event and Jim will be organizing food service. Mark this on your calendar and please respond to Jim when he asks for assistance. Scott reviewed the FAA proposed rule changes. He encouraged all of us to write the FAA and various representatives. The FAA comment window is only through March 2. This can be a brief paragraph or two, but the most effective can be those that are personal and how it will affect you. Thanks to Scott for keeping us up to date on these proposed changes and encouragement to stay involved. Larry presented plans being made for a new maintenance shed. It will use the current concrete pad including the open extended area. The idea is to enclose the entire pad, with a wall to separate equipment from a “clean” area for water, snacks, etc.He is in the early design stages so if you have ideas on what you would like to see, or concerns we need to consider please contact Larry in the next couple of weeks. He wants to move from prelim design to a working design so he can begin filling in cost estimates. Right now, it’s looking in the neighborhood of 6-8 thousand dollars. After we have an idea of costs we will begin to line up funding sources, such as City of Richland Parks and AMA grants.Thanks to Larry for his effort in gathering information about siding, roofing, etc. Next meeting is March 19, 7:00 PM, Ranch and Home conference room, Colombia Park. Hope to see you soon at the field, John
Slow Survivable Combat (SSC). SSC is the most popular class RC Combat has to offer. Only having a .15 engine and a rpm limit (17,500) reduces the speed and the severity of the crashes that are bound to happen.
The objective of SSC is to recreate the excitement of aerial combat in an enjoyable, safe competition that will be interesting for spectators and challenging for the contestants.
Combat is the most exciting five minutes you can have in RC! There’s nothing like chasing your opponent as he dives for the deck, turning left and weaving right! All of a sudden somebody’s on your six, you pull up and head for the sky. You yank a hard left turn and just barely escape with your streamer still intact.
Combat is flown with a 30′ streamer tied to each pilot’s airplane. The object is to cut your opponent’s streamer while trying to protect your own streamer. Points are awarded for how many kills (streamers you cut) you get, and how much of your own streamer you bring back from the battle.
Although referred to as Slow Survival Combat, don’t let the name fool you. A five minute mission provides an ultimate adrenaline rush. Believe me, after the five minute mission and with your plane safely back into its stand, you will appreciate the 15 minute break between missions. Each day of competition consists of six, five minute missions.
The planes are a construction of aluminum rails, .15 size engine, covered foam main wing, tail wing and stab cut from sign board, 3 servos, a fuel tank, battery and receiver. There is a minimum weight limit of 2.5 lbs. The engine RPM is limited to 17,500 (approx. 50 – 55 mph), 8×3 propeller.
A complete set of rules can be found at RCCombat Association web site.
I have enjoyed the thrill of competition in the past, and would like to start a group within our club. If this is something you may find interesting or would like more information, please contact Jim Anderson @ 509-554-2711 or by email at firstname.lastname@example.org.
Ever have one of those days when you really want to go to the field, but now that you shouldn’t. Well yesterday was one for me.
I arrived at the field around 10 am, weather ok, winds very low. Shortly after arrival, a single cloud opened up and it started to rain. Another sign that flying was not in the cards for me. But I waited it out and the rain stopped.
I have been resurrecting an aircraft that Bill Bowen passed on, a beautiful BlueHawk bi-plane. The resurrection finished out very good, the plane looked great. So today would be its Maiden Flight.
Started the engine, warmed it up, did a bit of tuning and then off to the runway. A bit nose heavy, but controllable, I raised the throttle and headed down the runway for a fairly uneventful take off. As I climbed out, I noticed she was a bit heavy on the right side and needed a bit of left aileron to maintain level flight. Not a problem, continued to climb and make my right turn in preparations for trimming. As I came out of the turn, still climbing, the aircraft decided to do a trick of its own, an inverted dive. With little altitude to correct, the impact with the ground was inevitable. Picture below shows the rest of the story.
After collecting the wreckage, I brought out my back up plane for the day. A high wing trainer that I have flown many times. I had just finished a modification to the wing mounting, by adding wing bolts and wood pins to hold the wing on. Was kinda tired of searching for and using the rubber bands.
So, off to the sky, flying pattern circles, figure eights, and then loops. First loop ok, second loop not so much. A the plane came to the top of the loop, the main wing decided to exit the airplane floating gracefully to the ground. The rest of the plane became a high speed lawn dart.
So, I loaded the truck with what I had left, gathered all the debris and headed home, to where no doubt, I should have stayed.