Wednesday, May 21, 2008

One small step

Ok, first post! And I just put up my main site: (still working on the imagery)

It's a cliche' to say that a journey of a thousand miles begins with one step, but it's also true. Consider that today we fly men to space, but in 1903 the Wright brothers' first flight lasted only 12 seconds.

So, with two months until helicopter school, I've been reading the Rotorcraft Flying Handbook, the official text by the Federal Aviation Administration.

I was surprised to learn how unstable a helicopter is in a hover. Intuitively, I thought being still would be easiest, a state of rest, like sitting still in a car. But it turns out a helicopter in hover is constantly trying to turn or twist or fall, throwing itself off balance and out of hover, so the pilot has to constantly adjust to keep it there.

To do so, the pilot acts like a drummer, or a one-man-band, constantly monitoring and adjusting many things at once, in concert, with both feet and hands.

For example, suppose you're hovering, and the helicopter begins to slide left. To compensate, you must lean the rotor (the spinning blades) to the right. When you do that, the helicopter loses lift and starts to fall, so you have to adjust the angle of the individual blades to prevent a descent. When you do that, the blades dig more air and begin to slow down, so you have to increase the throttle to maintain their spin speed.

When you do that, the spin of the rotor causes the helicopter's body to spin the opposite direction (like when you shove something big, you fall back too), so you have to adjust the tail rotor to maintain your heading. If you do any of these cascading reactions imperfectly, the helicopter will start to slide or fall or twist off in a new direction, and on it goes...

Everything in the above two paragraphs happens almost instantaneously. Now I understand why rescue helicopter pilots need 100% concentration to stay precisely over their target. It's a very delicate and fragile state of balance.

I'm planning to get to Hawaii on July 13, so less than two months until I start learning how...

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