In every sport, regardless if it's water skiing, boating, baseball, or football there are safety issues and safety rules designed to keep both the participants as well as spectators, as safe as possible.
Where a sport uses machinery, like skydiving, the airplanes are routinely inspected for problems which could lead to a malfunction, thus jeopardizing pilot, jumpers and people on the ground. Parachutes, harnesses and lines are inspected for the same thing. Many participants in the sport keep themselves in good shape either through exercise, diet or both. The concern is that with careful planning, examination and care of related equipment (even the human equation), the chances of catastrophic failure is dramatically reduced - but never eliminated. Don't we all wish we could eliminate bridge failures, high speed blowouts and other life threatening or injury causing accidents?!
"Helisafety" is my own fabricated word that simply refers to the extra measure of respect that I believe should be given to model helicopters. I have been flying helicopters for over a year now, but until recently didn't think too much about the safety side of things. I suppose I'm like anyone else new to the hobby - the thrill of finally being able to hover my heli until near fuel exhaustion, completing that first loop and executing that perfect auto has been foremost in my mind.
I have taken "normal" precautions in my flying however and have not sustained any injury. Could this be from my over 15 years experience with flying airplanes? Well, possibly. But I have also had a couple of close calls which I'll share with you as well as offer some suggestions on how accidents can be prevented. Whether you are a novice or expert, it's all in your attitude you know. I believe that accidents with model aircraft of any types come from one of two sources; Attention Lapse, and Mechanical failure.
CATEGORY CONTENTS COMMENT
Electronics Receiver Secure
Servos Secure/screws tight
Gyro Secure/working properly
Batteries Secure/Charged
Wiring Secure/plugs plugged in fully
Head Main grips/brg./blades Bearings free/blades in good shape
Flybar/Paddles Flybar straight/paddles aligned
Ball links Free-not loose
Fasteners Tight
Tail Gearbox/drivetrain Secure/lubricated
Tail rotor/beg. /blades Bearings free/blades in good shape
Fasteners Tight
Engine Clutch Alignment/lining in good shape
Fuel lines Good shape/tight
Main drive gear Good shape/free play at minimum
Fasteners Tight
CHECKLISTS
Something that full-scale pilots use before they even start the engine is a checklist. Part of any checklist is a pre-determined list of mechanical things to look at to see if they both operating properly, as well as set in a particular way prior to flight. Do you use one? I have a little checklist that will ever be imbedded in my brain after a close call with the main blades on a Concept 30.
After fueling, I carefully ensured that both transmitter and receiver were in the "on" positions. I connected the starting battery, held the main rotor blades in my left hand, pushed the starter against the starting cone and pressed the switch. Almost immediately the engine came to life - at mid throttle! The little heli wrestled itself from my unprepared grip and proceeded to flop itself against the pavement getting ever entangled in the glo-wires and nearly taking my sunglasses (dangling from their cords around my neck) with it. It took a second or two until I realized what had happened and somehow I managed to grab the fuel line and rip it from the engine.
The silence was deafening! I was glad that I was in my driveway and no one had seen this embarrassing sequence caused by Attention Lapse. After I'd collected my senses, I glanced one more time at the beast, ensuring it would move no more. Then I realized what happened. I had started the engine with the "idle-up" switch in the "on" position.
Luck was with me that day! The heli was still in one piece, the blade tips were chopped a little, but still perfectly fine and my hands and face were still just like they were before I had begun. The checklist now imbedded in my brain? How about before connecting the starter battery or pulling the starter cord, checking ALL switch and stick positions. Oh I don't just glance at the transmitter - I physically touch each stick and switch. Disaster had come too close to me. Those sunglasses? They are either on my face or on the ground - never dangling in harm's way.
Another time, I started my heli, ensured both transmitter and receiver were "on" and proceeded to increase the throttle. Suddenly the heli lifted off and the tail swung wildly left. I counteracted, and the tail then swung wildly to the right. Left - right - left. This was no close-order-drill march! I was totally unprepared at my stage of learning and could barely maintain a decent hover, let alone command a wild flying creature. It seemed to have a mind of its own and in my fear, I plopped the heli down a little too much to one side for the main blades. They hit the ground and splintered. What happened was simple enough - I had forgotten to turn on the gyro.
"So many things to remember." I told myself, when I first got into this hobby, "I wonder if other people made these same mistakes." Well, chances are many more people than I care to imagine have made these mistakes and others. But the point you see, is neither to dwell on these mistakes or "hanger fly" them. It is to say we're all human and we make mistakes. The main idea is not to make the same ones someone else has made. So here goes, I have provided a checklist that you could use to help prevent some heli mistakes.
I'm sure many of you have other ideas because of things that might have broken in flight or might have been prevented with a pre-flight check. If so, please feel free to write Rotory's Q&A and let us know. Others will find your information useful if not plain "Heli-Saving"!
ATTENTION LAPSE
As I said, I believe that accidents are caused by one (or both) of the reasons mentioned earlier. Let's explore the first. Attention Lapse is my definition of not being totally aware of what's going on around you when you are starting, flying, or landing. I guess we're all guilty of it at least once in our lives, eh?
Starting a helicopter can turn out to be more exciting than should be, as my previous example illustrates if you haven't checked the sticks and switches. But what about other pilots and spectators? The rotating blades of a model helicopter spinning around are like little meat cleavers. There is a popular ad now for main rotor blades which reads; "The air is butter. Here is your hot knife." I really like this ad because I think it describes rotor blades perfectly. Do all of us ensure before we advance the throttle that the area around the helicopter, and behind us is clear. Once as I was about to bring my heli into a hover, I began to move backwards to give the heli a little more room and nearly tripped over a spectator who wandered up for a closer look.
Imagine if I had been in a hover, backed up and actually tripped. I probably would have been startled and lost control of those rotating butter knives. Ouch! Be sure you know what is happening at all times around you and your heli. At our field for instance, pilots are not allowed to rev up their airplanes in the pit area because of the noise and because the thrust tends to blow things around in the pits, among other reasons. Although airplanes with running engines and 9" to 24" of propeller are dangerous, helicopters with 50+ inches of spinning blades are in my opinion, even more potentially dangerous. Tip weights in our blades give them tremendous inertia and the results from even a low speed blade strike can be amazing.
Once I was practicing autorotations on a windy day and the last one of the day got away from me. I had glided the heli too far past me but it was only about 4 feet from the ground. I had a bit too much forward speed at the end of the auto and the heli was tilted too far back. The blades were spinning fairly slowly by this time and the tail stinger hit the ground before the skids resulting in a boom strike. But the part of that muffed auto that amazed me (and made me angry) was that the blades only hit the boom once, but it was enough to send splintered blade tips out of sight, bend the tail boom, and break a main rotor grip and some miscellaneous parts. I cannot even imagine the potential damage from blades screaming around at 1700+ rpm under full engine power and striking something or someone! Perhaps someone versed in engineering could do an article in Rotory describing the energy in spinning rotor blades and relate it for us non-engineer types.
Before I forget, let me caution you about carrying your helicopter while the engine is running. You know, you're all excited, it's a great clear-blue-sky-day and you can't wait to get to the flight line. A word of caution here for something that happened to me while walking to the flight line on just such a day. I was carrying the transmitter as I normally do when a gust of wind caught my shirt and my shirt hit the throttle / pitch stick of the transmitter. Well, it wasn't enough to cause me to drop the heli, but, hearing the engine suddenly rev "without reason", and feeling the clutch engage got my attention quickly. Now I carry the transmitter with my thumb over the stick.
So there you have it: Attention Lapse. Be aware of your surroundings when flying. Give lots of respect to those meat cleavers and plenty of attention to your takeoff and landing areas for stray people and pets.
MECHANICAL FAILURE
I include radio failure also in this section. How many accidents might be prevented with just a preflight inspection? I have seen aircraft go out of control and crash. But when airplanes hit the ground, it's pretty much over. Heli's send their spinning parts over great distances at fantastic velocities. The "trick" therefore, is not to crash your heli due to mechanical failure.
Preventing mechanical failures is easy if you can anticipate what can go wrong. So where is your crystal ball? Really! I think some common sense helps a great deal in this regard since few of us are gifted with second sight. If we break a heli down into general categories of components, and look at each category, the things to inspect won't be so overwhelming. Here's how I do mine.
Once I had a crash when a ball link controlling the elevator on my Concept 30 decided to part from the ball. If I had been checking the links all along, I'd have noticed that it was getting sloppy and wouldn't have had to spend 10 times the money replacing blades and tail boom - not to mention the time it cost me. If only...
PRIOR TO FIRST FLIGHT OF THE DAY
1) Mechanical - Check linkages, servo mounts, T/R, gears, fuel line.
2) Electrical - Check all plugs, batteries, gyro for security.
3) Radio - Range check, battery level.
4) Main Blades - Tracking, security, cracks and dings (also tail rotor).
5) Fasteners - Looseness.
6) Oil - As required - swashplate, tail rotor.
DURING THE FLYING DAY
1) All above.
BEFORE EACH FLIGHT
1) Frequency - Check frequency and indicate which one you are using.
2) Fuel - Full.
3) Switches - Trans/Receiver/Gyro "on" and in proper position.
Batteries too require attention. Treatises have been written on NiCad recycling but the bottom line is that if you forget to charge your batteries, you are gambling with the life of your helicopter and possibly the life of you and others. Why take the chance? Charge your batteries and monitor them with an Expanded Scale Voltmeter (ESV).
I used to subscribe to a publication relating to full scale airplane crashes so that pilots could learn from each other not to make the same mistakes. Do you know what the cause of most crashes were? Fuel exhaustion. Unbelievable but true. Of course, I have passed many a gas station in my car because I was in too much of a hurry to get home. Fortunately I always made it. Was I foolish? Yes possibly, but would I do the same in an airplane? Do you have to ask?! So why then do we attempt to do that last autorotation, that last loop, that last go-around when we know our helicopter is low on fuel? That's one for the crystal ball, I guess!
Helicopters are subjected to lots of vibration and if you don't know about threadlockers, now is the time. Threadlockers are liquids like blue Locktite, or Pacer Technology's Z-42 that are used on the threads of fasteners. Remove all traces of oil from the fastener with say, acetone. Apply the threadlocker to the fastener and assemble the component(s). After about 30 minutes, the threadlocker is dry and the fastener won't vibrate loose. When you want to remove the fastener, all that's required is some good old elbow grease carefully applied with a wrench or driver. All helicopters use nuts with the plastic inserts to prevent separation in critical areas, so threadlockers aren't needed there. Basically the rule of thumb is; "If it screws into metal, use a threadlocker."
Oh sure, there's lots of other kinds of mechanical things to look for, but my intention is to get you thinking about possibilities. I think it's a good idea to tear down your heli every once in awhile (depending on your flying schedule) and give it a good going over. Pay particular attention to bearings and bearing surfaces. Sometimes a shaft running inside a bearing will turn at a different speed from the bearing due to friction, dirt, or whatever and the shaft will wear and will then have lots of "play". Some folks use blue or green Locktite on the shaft where it contacts the bearing race to actually lock the bearing and shaft into one unit thus eliminating wear on the shaft. When you eventually want to separate the two, it can be difficult (some say heat works), and if you get threadlocker inside a bearing - woe to you! So be careful.
IN CONCLUSION...
A safety item which has become part of my flight box is a simple set of earplugs. One thing that really makes me tired and gives me headaches is prolonged exposure to loud noises. When I cut my grass, trim the hedges, etc. I've always got my earplugs in. Think about hovering practice therefore, when your heli is close to you all day. Well, for one thing, you're busy concentrating on the heli, and that makes your muscles tense. Add to this, the drone of an engine close by and you've added another dimension of stress to your already stressful situation. Now do you wonder why you're tired after a few tankfuls? I've found that by simply cutting out the noise of my heli engine, I was able to apply more of my energy to the hovering itself - plus my hearing no longer suffers.
In conclusion, I wish I could guarantee that if you carefully inspect your heli, that all crashes could be prevented. For some reason, life isn't like that. I suppose there's always that engine that will throw a rod, or that bearing that will suddenly go bad. Life is a risk and a gamble. By working hard however to minimize the dangers to ourselves and to others, I can promise you a faster learning curve, more enjoyable flying, and less repair time. I remember coming home from the flying field one day and finally being able to tell my wife; "Honey, nothing happened!" It is the intention of Rotory and myself to share experiences discovered either through actual flying or from conversations with others so that we all can enjoy this tremendous sport without incident. Have fun, be safe and enjoy your heli! / NICK SACCO
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