Safety Comes First
Box 4520, Milton FL 32572-4520
CHECK IT OUT: I've been modeling for many years, but it wasn't until I began full-scale flying that I learned to appreciate the purpose of using checklists.
In full-scale flying, checklists are used to ensure that pilots conduct a review of aircraft systems and/or procedures prior to each flight. Using them in this manner almost always guarantees an airworthy aircraft; in other words, anything deemed as not meeting standards during the preflight is generally fixed or the airplane doesn't go in the air.
How nice it would be if modelers followed the same path and taught similar values to newcomers.
Although the use of checklists is recognized as necessary in full-scale to ensure safe flying, in modeling it's been my experience that unless the checklists are found in newsletters, magazines, or columns for general review, it's rare to find someone actually using one at the field. Maybe that's because it doesn't take modelers long to get a procedure down, or because we fly many different types of aircraft and think we need numerous lists (overwhelming or too time-consuming).
Whatever the reason, if you stick with the hobby for any length of time, or if you've just started, you'll definitely benefit from the use of a list.
While I was scanning radio control (RC) links on the Internet, I clicked on a list from the Chester County (PA) RC Club that can help you get started. Feel free to modify it for your own situation and use it at the field.
Think of the "Preflight Checklist" as a walk-around check, as done with full-scale aircraft!
Preflight Checklist
Propeller
- Nicks or cracks
- Tight prop nut, spinner, or hub
Engine
- Engine mount tight
- Muffler mount tight
- Secure throttle hookup
Fuel Tank
- Check fuel line for splits and holes
- Foam used around tank dry and secure
Landing Gear
- Nose wheel and main gear secure
- Axles and wheel collars secure
- Nose wheel steering hookup
Fuselage
- Cracks or breaks
- Tail section secure to fuselage
- Wing dowels or bolts secure
- Firewall integrity
Vertical Fin / Rudder
- Cracks or breaks
- Hinges, clevises, and horns secure
- Pushrod play and keepers
Horizontal Stabilizer / Elevator
- Cracks or breaks
- Hinges, clevises, and horns secure
- Pushrod play and keepers
Wing
- Cracks or breaks, especially center section
- Hinges secure
- Aileron and servo hookup secure
- Aileron servo tight
Radio Check
- No loose servo or battery wires
- Plugs tight
- Battery pack secure
- Servos and servo rail secure to fuselage
- Clevises and servo wheels/arms secure
Engine Running / Radio Operation
- Bubbles around glow plug, head bolts, muffler, or needle valve
- Bubbles in fuel line
- Control surfaces move smoothly at full throttle — no glitches
New Student Hints and Tips
While reviewing the official newsletter of the Greenville Flying Pirates Model Aircraft Club, I read a paragraph that explained what behavior to expect from your airplane during its first flight.
I remember my first flight, during which, after release (hand launching), the airplane covered the entire sky like a party balloon losing air, prior to crashing into a heap at the end of a ball field. In those days, not much sophistication (or money) was lost, although safety of the people gathered around was a factor, as was the loss of a model that took significant time to build and cover.
I've always believed in passing on knowledge to make learning easier and prevent mishaps, so a review of the following is in order:
There are a few things that a student pilot should keep in mind when preparing for each flight; these will help in getting the feel for the model in flight.
Be very gentle with the controls; it takes very little movement to get the model to execute a maneuver. Remember, the farther the stick is moved, the more the control surface moves and the more the model will respond. As long as the stick is held in a control position, the maneuver will continue—this is most important when using the ailerons.
When the stick is moved to roll the model, it will continue to roll as long as the stick is held in that position—fly it in, fly it out. When a maneuver is executed, it takes equal and opposite controls to overcome it and return to normal flight. A turn requires the movement of the ailerons in the desired direction of the turn. To recover from the turn, the opposite aileron input is required.
Keep the model high when landing; the runway that is behind the airplane after touchdown is wasted because there is a reduction in the length of runway to take off again in case of trouble.
Keep the model in sight; do not fly too high or too far away. Although the trainer may seem fairly large, it is easy to get it far enough away that it is difficult to see its orientation. Do not fly into the sun—a moment of blindness caused by the sun can be long enough to lose a model.
Do not become discouraged. There will be times when nothing seems to go right. There will be nights when each maneuver results in a near-catastrophe. Everyone who flies RC models has been through this when learning to fly—do not give up. The next session will be better.
Do not panic. When a maneuver goes wrong, take all the time necessary to recover from the mistake. Panic will cause a student to overcontrol in an attempt to recover and make the condition worse in the opposite direction. Although the instructor may seem to be a casual observer standing at the side of the student, he will be watching and will take over if you get your model into a dangerous situation.
Storing Ni-Cd Packs
Although I usually write a note at the end of flying season about battery maintenance, I felt the need to do so this time after a recent trip to one of my models yielded dead cells and a case of "black wire disease" (wire and circuit-board corrosion from leaking batteries).
A failure in the workshop is preferred to one at the field. It seems that since I moved south, my batteries just don't last. I'm often asked how one detects an imminent failure, but since I'm not that electronically savvy, most of my answers point to the "crystal ball."
If you'd like to have safe and reliable batteries when you need them, and/or want to learn about black wire disease, battery guru C.L. "Red" Schofield provides some insight:
How should I store my batteries at the end of the season? What should I do to them when I put them back in operation? The batteries should be removed from the transmitter and airplane for long-term storage. Here in the South, where a lot of us work out of our garage workshops, I recommend putting the batteries in the refrigerator (not the freezer) during the off-season. While this is not so important if your workshop rarely gets above 23°C (74°F), the refrigerator is still a good bet.
Why? The failure mode of Ni-Cd cells is separator failure; this is the material that keeps the plates from touching each other. When it fails, the cell shorts. At higher temperatures, it oxidizes faster—the rate doubles for every 10°C increase.
Should I store my batteries charged or discharged? It doesn't really matter; they will self-discharge in a few months if stored at room temperature. If you are going to store them in the refrigerator, the charge will remain longer; I would discharge them first to 4.4 volts and then put them away.
Good cells will just sit there in the discharged condition (the voltage can vary considerably but is usually more than one volt). In a battery with a damaged (worn out) separator in the cells, the cells are apt to short if left in a discharged condition. This is actually good, since it's the first indication of a cell that's going bad and it is best to replace the pack.
A battery left on trickle charge will seldom short out, since it is in the charged condition; any short that tries to develop will be zapped by the charge in the cell. Partial shorts (those having fairly high resistance) can be developing; this can cause the cells to self-discharge at a higher rate than normal. It can also possibly leave you short in the middle of a flight, after you measured the cell when it came off charge with your Expanded Scale Voltmeter (ESV) and everything looked okay.
The reason I recommend removing the batteries from the transmitter and airplane is to protect against black wire disease. If a cell shorts while in storage, there is a high probability that there will be some leakage that can ultimately lead to the black-wire problem.
When your batteries are coming out of storage, check the voltage without a load on the battery before charging. It should read more than four volts, even if they have not been charged all winter. They should essentially be fully discharged (or flat, as we say in the business). In this condition, if the battery is going bad, it will probably have shorted and you will read zero volts on that cell. It may be a soft short—one that could be blown away merely by the simple action of slow-charging. Don't do it! It is just lying there waiting to bite you.
Replace the pack; if you want, cut out the "good" cells and use them in something less critical than your model. If you have access to a cycler, running through a couple of charge/discharge cycles is a good idea, just to make sure you are getting the capacity you are supposed to. Anything less than 80% of rated capacity is suspect.
Once at the field, preflight battery checks are in order, particularly at the beginning of the season. Since the people who religiously check their packs with an ESV seem to crash less (because of battery failure), one must assume that the ritual is smiled upon by the RC gods.
Safety is No Accident
- Fly safely.
- See rule #1.
Till next month.
Transcribed from original scans by AI. Minor OCR errors may remain.
