Reflections on a Wandering Life.....

Monday, December 30, 2019

Science Night - What is a gyrocopter? 

What is a gyrocopter? It is probably the most misunderstood aircraft. Gyrocopters came into the news a few years ago when a postal worker from Florida landed a gyrocopter on the White House lawn. I was amused to see news personalities refer to the craft as a "small helicopter." A gyrocopter is not anything like a helicopter. It looks like a helicopter. But that is where the similarity ends.

A gyrcoplter does not fly like a helicopter. Everyone knows how a helicopter flies. A giant rotor spins and creates lift. But a gyrocopter could never fly like that. Why? Because the rotor on a gyrocopter has no motor attached to it. It is free-wheeling. What good is a rotor that doesn't even have a motor? If you look at a gyrocopter closely, you will see that there is a propeller behind the airman that pushes the craft forward. The forward motion of the aircraft causes the rotor to spin, and once it starts spinning, it essentially becomes a wing. So a gyrocopter flies just like a fixed-wing aircraft. But why would you want to use a spinning rotor as a wing instead of a regular wing? Because a wing made out of a solid sheet of metal (even aluminum) with that kind of wing space would be much heavier.

I always used to say that the gyrocopter is the original ultralight, because gyrcopters were ultralight when ultralight wasn't cool Ultralights became popular in the seventies and eighties. It started with hang gliding. Hang gliding became a fad during the time that I was in college. I remember when a guy jumped off of Pike's Peak with a hang glider. Later they started adding motors to them. So the first ultralights were basically motorized hang gliders. In fact, that's what I used to call them. I did not hear the term ultralight until later.

In contrast, the first gyrocopler flew the year my father was born (1923). But it must be admitted that the first gyrocopters looked more like conventional airplanes than ultralights, so perhaps it is more accurate to say that when the ultralight movement started, it was easier for the gyrocopter to adapt to that mode, since it had always been designed as a craft that could be aerodynamically efficient at slow speeds. It was a natural fit.

But I need to be clear that having a free-wheeling spinning rotor is not the only way to create a wing that is light-weight. The Rogallo wing for example, which I will talk about another time, was made of fabric, which is very light. So as the ultralight movement has developed, experimenters have found other ways to create lift with a very light wing in a way that allows efficient flight at slow speeds.

Years ago, when I was in the trucking industry, I worked for a flatbed outfit out of Fargo that had a contract with Reynolds Aluminum. I hauled many loads of aluminum out of the huge Reynolds plant in McCook, Illinois, a suburb of Chicago. One time had a load of wing skins going to Boeing in Auburn, Washington. If you saw those huges sheets of metal, you would not believe they could fly. They were very thick and very heavy. How can something like that be made to fly? The answer, of course, is speed. I heard once that you could fly the Empire State Building if you could get it going fast enough.

So speed compensates for weight. But if you want a vehicle that flies slowly, it needs to be very, very light. The gyrocopter was really an ingenious way to do this. Not the only way to be sure--as I said, as the ultralight movement has developed there have been many innovations seeking to maximize lift by minimizing weight.

Now back to the guy who landed on the Capitol lawn. Aside from being amused at how the news media couldn't resist calling a gyrocopter a "small helicopter," I was curious to see how the law would deal with a guy who was basically harmless--he obviously wasn't a terrorist--but who had violated very serious laws about flight safety and security. Landing on the lawn of the Capitol is quite obviously a breach of security that should not be taken lightly.

He got a four month jail sentence. I think the reason they gave him such a light sentence was because he was clearly not a terrorist. He did not hurt anybody and did not intend to. But I am not concerned about the threat to the Capitol. I am more concerned about the threat to general aviation. I don't know any country in the world that gives experimental airmen as much freedom to innovate as the United States. This is a privilege that should not be taken lightly. There is nowhere near that kind of freedom in China. When one person abuses that privilege, it is jeopardized for every other flyer. Countries that do not have a strong general aviation system are forced to borrow innovation from countries that do. That is just a fact. This guy was not a terrorist, I get that. But he was not a hero either. He did not really put the Capitol at risk. But he did put general aviation at risk. He should not be allowed to fly.



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