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# Drag Equation for approach angles

## Drag Equation for approach angles

(OP)
I need some help trying to visualize a discussion I am having with a colleague.
At a constant speed, will the approach of an aircraft at a steeper angle be more or less stable then a shallow/flat approach that is reliant on thrust in order to maintain lift?
The way we are visualizing the issue is, in the shallow or flat approach, if the aircraft is reliant on engine thrust to maintain flight, for instance at a 2% approach - it would have less ability to respond to deviation in the flight condition. However, if it takes a steeper angle, say 7 or 8%, while maintaining the same constant airspeed as the 2% example, the AoA would be higher and therefore have a higher drag coefficient in the steeper approach.

### RE: Drag Equation for approach angles

You have to balance the energy equation with rate of descent, too. As you descend, you are gaining kinetic energy.

No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF

### RE: Drag Equation for approach angles

everything is interrelated !

a specific descent rate requires a specific angle of attack; as Sparweb notes, there's vertical energy to be considered. So a 7% descent rate would not happen at the same speed as a 2% rate.

### RE: Drag Equation for approach angles

Having the engine throttled up (especially with turbines) means the response to full power is much quicker, i.e. in a go-around situation.

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