I have never been able to figure out helicopters. The big propeller obviously makes them go up and down, but how do they go backward, forward, and sideways? I happen to know the little propeller in the back is needed to keep the helicopter from spinning like a top due to engine torque, so that can’t be it. Any ideas? –L., Chicago
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Any ideas? Not to belittle your question, friend, but I’ve had more trouble figuring out the directions on a cracker box. Helicopters go forward and backward by altering the pitch of the main rotor blades, i.e., the angle at which the blades meet the wind. Up to a point, the steeper the pitch, the more lift, as you know if you’ve ever stuck your hand out the window while driving and waved it in the airstream. The trick is to alter pitch unevenly, so you get more lift in, say, the back of the helicopter than in the front. This is accomplished with the system of rods and levers you see near the rotor hub. To go forward, the rods increase pitch (and thus lift) when the rotor blades are in back of the helicopter and decrease it when they swing round to the front. This causes the helicopter to tilt forward and the rotor proceeds to pull it ahead.
Years ago the media had a big hype about the discovery of the Dead Sea scrolls. Since then, nothing. Were the scrolls translated? What, if anything, was discovered? Or is this another dry hole like the shroud of Turin? –A. Barnes, Towson, Maryland
