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Easier way to keep a steady speed without Autothrottle?

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Hello all!

I was just wondering if there was an easier and more efficient way to keep a steady speed in a plane without Autothrottle? The plane I usually fly in is the Cessna 172SP G1000, one of the default aircraft in FSX. The way I currently hold a steady speed is buy adjusting the throttle to a point where it stays at a certain speed. I would really like to know if there is a more easier way to hold a steady speed, or if there's not. Maybe there's a way to do an autothrottle-like thing?

I usually try to keep a steady 100 knots, and I only use flaps when I'm taking off. I usually land at around 80-95 knots, much faster than you should. The plane still stops in time, though. :happy:

Also, I use my keyboard as my "controller" and I use the mouse for Mouse Yoke. I'm planning on getting a CH Eclipse and CH Throttle Quadrant for Christmas this year, but the equipment for FSX that I have right now is pretty bad. It would be very well appreicated to tell me an easier way to hold a steady speed, if there even is an easier/more efficient way.

Thanks!

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There's either manual throttle or autothrottle.  Nothing in between.  But once you set the power and trim the aircraft out it should maintain speed.  However.  You could assign a key press to FSUIPC Speed hold.  It's basically like adding autothrottle to a non autothrottle aircraft.

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That's the only way to fly a desired speed without an autothrottle. That's how it is in the jet I fly. It doesn't change. In Cessna 172 though, just set it to a power setting you want and trim for level flight. Eventually, you'll stabilize at a speed that coincides with your pitch and your current power setting. As long as you don't change pitch or power, you'll stay at said speed.

 

I.e. set the throttle to wherever you want it and just fly level....set it and forget it

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Depending on where you learn to fly, there are usually two different methods for controlling speed. In the military (where you'd most likely end up flying a high powered jet), pilots are often taught to control the speed with throttle and use pitch to control the rate of descent/ascent, conversely, most civilian private pilots are taught the opposite, i.e controlling the rate of ascent/descent with power settings and using pitch (typically by trimming the angle of attack) to control the speed. Having said that, most pilots end up doing a bit of both. Whilst you are using the keyboard and mouse, you might find that using the trim commands for various throttle settings will help to stabilise your speed (the default keys for FSX are Numpad 1 and Numpad 7 for trimming nose up and nose down), use small increments and see the effect, then adjust as necessary.

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Thats where having a really nice throttle controller comes in. In a real plane you make minute changes to the throttle. Depending on how the winds are going and the atmospheric pressure you will get a outcome on the setting. In a sim it becomes harder becomes one small move to the throttle is sometimes a drastic change in the actual throttle.  

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Power + attitude = performance.

As described above really: just set the power and pitch attitude required for level flight and let the airspeed settle. In the C172, 2200 rpm in the level flight attitude will give you pretty much 94 KIAS. You may get slight fluctuations due to atmospheric disturbances but generally you do not want to be chasing these deviations unless they are sustained and unacceptable: if you change the power you will also need to change the attitude, which will require re-trimming and thus will get a different performance (ie airspeed). If the airspeed (performance) has changed then either the pitch attitude or the power setting is wrong and will need adjustment.

For 100 KIAS you will need, I would guess, about 2300rpm and a slightly lower nose attitude than would be required at 2200rpm/94 KIAS. 2400 rpm (and a consequently even lower nose attitude) will give more like 105-110 KIAS.

Above the minimum drag speed  (about 68 KIAS in the 172) the aeroplane will be speed stable: that is to say that if the airspeed increases, drag will increase and tend to cause the airspeed to reduce back to the trimmed value. Conversely if airspeed decreases, drag will also decrease and therefore the airspeed will naturally again tend to return to the trimmed value.

Below the minimum drag speed - on the 'back side' of the drag curve - a reduction in speed will result in an increase in drag and vice-versa: thus below this speed the aircraft will be speed unstable. The result is that when flying at these (low) airspeeds you will need to be much more active on the throttle to maintain a given airspeed.

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