Before I became a student of Graphic Design, I had a number of hobbies that almost satisfied my creative mind during my non-foodservice hours. One of these pursuits was radio-controlled helicopters.
An RC helicopter is not a new invention, but advancements in nickel-cadmium batteries have pushed the hobby into the next level in the past decade. Previous models ran on kerosene fuel or even actual jet fuel. They were loud, expensive, and dangerous. Modern choppers can be much smaller and lighter. The batteries only last between ten and twenty minutes, but they are stable, and you can swap them out easily. The ultra-light helicopters can be flown indoors and are unlikely to cause any damage. Gyro stabilizer units can be made extremely small and cheaply, so the newest choppers can self-level with ease, making flight less of a learning curve. After a few weeks of flight experience, I quickly outgrew my entry-level chopper and wanted to get something more expensive.
The helicopter is a remarkable invention. An airplane has a natural stability. Fold a halfway decent paper airplane and it will glide gently to a sliding stop on a smooth floor. Air travelers can take comfort in knowing that an airplane wants to stay flying. A helicopter is another thing entirely. The chopper is completely dependent on its engine. Lose power and the vehicle falls like a rock. Helicopters are profoundly dangerous. It is a testament to their usefulness that anyone ever boards one. The ability to take off straight up or to stop midair makes the most dangerous craft viable.
My entry level helicopter lacked a collective pitch elevator. What is that? Well, before I began my heli-obsession, I assumed that the main rotor created lift by spinning faster. Like a desk fan, I figured a helicopter blade would rotate faster to blow more air downward, thus sending the craft up. Ultra-light RC helicopters and basic toys work in this way, but a real helicopter uses what is called a collective pitch elevator. The helicopter starts its engine and the main rotor begins to spin. As the engine warms up, the rotors spin faster until they reach the optimal RPM, but the helicopter does not lift off. This is because the rotors are not angled at all but are flat parallel to the ground. There is an additional mechanism that controls the pitch of the rotors while they spin at severe speeds. The pilot lifts with their left hand a lever called a manifold, which is similar to a parking brake in a car. This causes the rotors to change their “angle of attack” and lift is created. The rotors’ RPM does not change.
In order to accomplish this trick, the blades require an elaborate mechanism of rods to push and pull the rotors as they spin at high speeds. The parts are subject to immense forces and they are the most obvious point of failure for an already delicate system. A model helicopter obeys a different set of physical properties. A push rod three centimeters long made of aluminum is vastly more effective that its full-size counterpart. An RC helicopter can rapidly change its angle of attack, accelerating and braking at rates that would shatter a real helicopter. An RC chopper can also change its thrust in the extreme negative, creating a situation where the vehicle can actually fly inverted. YouTube is loaded with videos of the aerobatic performances these RC pilots have recorded. There are competitive events, of course.
So, my own heli-adventure led me to buy an intermediate level chopper with a collective pitch and the power to go upside down. My toy grade chopper had a main rotor diameter of about one foot, but this new one was closer to two and a quarter. The first time I fired up the engine I had no intention of lifting off, but the power was honestly intimidating. The spinning rotor stirred the air in my spacious living room. I spent days checking all the various control surfaces and made sure I had setup my craft correctly.
The first liftoff was outside. I rose about three feet off the ground and felt comfortably stable. I pitched forward just a bit, but the chopper leaned forward like and started towards my neighbor’s yard like a dog chasing a tennis ball. I was not expecting such eagerness, so I pulled back and now the vehicle was heading towards me with its main rotor coming at my face. I overcorrected forwards, and the rear rotor lifted up fast, and the chopper leaned into my lawn, bit into the dirt and whipped its tail around so hard it bent the aluminum boom shaft. I realized the controls needed to be much less sensitive.
My second attempt was much calmer. I took off vertically, rotated 360º slowly, and set it back down smoothly. I was confident, so I took off again. I tried moving forward a bit, but again the craft wanted to go faster than I was ready. I overcorrected backwards, but it was too much. When learning my light toy-heli, I often deliberately flew it into my pant-leg. The blades have hinges that allow them to retract when they encounter an obstacle, so they do not break with every collision. The new chopper had a similar hinge, but the blades were composed of thicker plastic, and the engine was much more powerful.
The heli came towards my left thigh, and I rose it to catch the rotor, but WOW that thing was rotating quickly. The blade hit my thigh so hard that I was not sure if I needed to get to the hospital or call an ambulance. I quickly examined my thigh and saw that my jeans had not been sliced although they were clearly scarred. I dropped my pants a bit and looked at my thigh which had two remarkably brutal bruises. The blades were moving so fast and hard that I broke a gear connecting them to the engine by impeding their rotation. Despite this, the second blade was still able to rotate around and strike me just as hard as the first. Both white blades were notably blue at their tips where they whipped my jeans.
Once the fear wore off, I was in an impressive amount of pain. I am not an outdoor kid or a sports player, so I can only assume this is a common occurrence to anyone who plays hockey. My leg turned all sorts of interesting colors as it healed. I repaired my chopper, but never flew it again. The year was 2015, and shortly after my accident, there was a story out of New York City where a hobbyist killed himself by accident when he flew a much larger RC chopper into himself. This gas-powered model is capable of speeds up to 90mph. When it collided with the pilot, he was effectively decapitated. After several months of consideration, I decided I would never fly it again, and sold my heli on ebay.