直升机信息_直升机_直升飞机_旋翼机_Helicopter

 occurrence are present and the helicopter does not respond to 
in, the mass does not change, but the radius of where that mass  cyclic inputs, there is a distinct possibility that dynamic 
is located does decrease. Therefore, as the skater’s moment of  rollover is imminent. What should a pilot do now? Lower the 
inertia and resistance to rotation decreases, her spin rate, or  collective. 
angular velocity, increases. 
Look at all the forces acting on the helicopter and see how 
For every helicopter, the manufacturer must determine the  they contribute to the rollover.  The thrust of the main rotor 
maximum control moment.  Each helicopter must, by U.S.  multiplied by its moment arm about the pivot points is in the 
military specifications and U.S. Federal Aviation Regulations,  pro-rollover direction. The thrust of the main rotor multiplied 
achieve a particular roll rate.  The manufacturer knows the  by its moment arm is also pro-rollover. The combined effects 
mass of the helicopter and how that mass is distributed.  of the wind are also pro-rollover.  Only the weight of the 
Therefore he knows the moment of inertia. The manufacturer  aircraft multiplied by its moment arm opposes the rollover. 
produces the helicopter so that, with full cyclic displacement, 
the rotor system produces a sufficient moment about the cen- Countering the roll with cyclic-only reduces the main rotor 
ter of gravity to change the angular momentum of the helicop- thrust moment arm.  Lowering the collective reduces the 
　
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