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How is takeoff airspeed affected by flaps?
Increasing flap angle increases the lift coefficient, and therefore reduces stalling speed and the required takeoff speed (the same lift will be created at smaller air speed due to greater lift coefficient). This reduces the takeoff distance. The flap setting also affects the climb gradient.
What is the takeoff roll?
Takeoff roll (ground roll) is the portion of the takeoff procedure during which the airplane is accelerated from a standstill to an airspeed that provides sufficient lift for it to become airborne.
Do planes have constant acceleration?
Yes! In physics, constant velocity occurs when there is no net force acting on the object causing it to accelerate. At a constant altitude, when the force of thrust equals the opposing force of drag, then the airplane will experience uniform motion in one direction.
What is the difference between positive and negative acceleration?
An object which moves in the positive direction has a positive velocity. If the object is slowing down then its acceleration vector is directed in the opposite direction as its motion (in this case, a negative acceleration).
Can there be negative acceleration?
It is not speeding up or slowing down, so it has zero acceleration. Because the velocity/speed of this object is decreasing over time, this means there is a negative acceleration.
Why does acceleration decrease when the aircraft is at rest?
Since drag is also lowest with the aircraft at rest, the highest acceleration is possible right after brake release. As soon as the aircraft rotates, the new lift-dependent drag component will cause a marked decrease in acceleration, and when the aircraft climbs, some of the excess thrust needs to go into climbing, so acceleration decreases again.
How is the takeoff and landing distance calculated?
The takeoff distance consists of two parts, the ground run, and the distance from where the vehicle leaves the ground to until it reaches 50 ft (or 15 m). The sum of these two distances is considered the takeoff distance. (Note: sometimes a 35 ft altitude is used). The takeoff distance is generally calculated for maximum weight in a standard
Why does the zero lift drag coefficient decrease with speed?
Since the flow’s Reynolds number also increases with speed, the zero-lift drag coefficient (aka friction plus pressure drag coefficient) decreases with speed.
When does the aircraft lift off the ground?
Depending on the ground attitude of the aircraft it will create already some lift during the rolling phase, but lift substantially increases during rotation when it is raised to lift the aircraft off the ground.