PPRuNe Forums - View Single Post - Angle of climb/rate of climb
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Old 29th Sep 2011, 20:19
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Pilot DAR
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Over a given time the steep climb will be higher but not so far "down range" the shallow climb will be not so high but further "down range".
Unfortunately not.

Two defined climbs are described as "Best Angle" and "Best Rate".

The "angle" is relative to the surface, so if you stood off to the side of the runway a way back, the airplane flying the "best angle" speed, would appear getting away from earth at an angle less acute relative to the ground, than a plane flying the best rate speed, which would have a more acute, flatter angle. The best angle plane will be moving more slowly across the ground, so combined with the steeper angle, will clear an obstacle that the best rate plane might not.

The "rate" is in feet per minute, for increase in altitude (does not care about distance over the ground covered). So flying the best speed rate speed will get you the greatest altitude in the least time, but you'll cover more ground doing it, so you might hit that same obstacle. So over a given time the shallow angle, faster airspeed, climb (at best rate speed) will get you to the highest altitude.

This is in part because there is more effect of drag at the lower airspeed of the best angle climb. You are flying with less than optimum efficiency, so you will climb at a slower increase in altitude per time (FPM) rate.

These speeds will change with increased altitude. When you get to the absolute ceiling for the plane, they will be the same, and alarmingly close to the faster stall speed way up there.
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