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Q & A: airplane speed on takeoff

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Most recent answer: 06/20/2013
Q:
Why does it seem that the airplane that just took off is going at a slow pace rather than the actual full throttle it actually is when viewed upon from a particular point on Earth? Keeping in mind the Earth’s gravitational pull?
- Luna (age 41)
East Elmhurst, NY
A:

The airplane really isn't at full speed even though it's at full throttle (maximum engine power).  There are two reasons.

1. The force from the engines shows up directly in the acceleration (F=ma), not the speed. It takes a while at high throttle to build up speed.

2. As the airplane is heading up, some of the work being done by the engine must go into lifting the plane against gravity, not just into speeding it up. 

 

Mike W.


(published on 06/20/2013)

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