Personal Summary of Basic Operations: Level Flight, Climb, and Descent

I’m writing this down now so I don’t forget it later.

To maintain a steady state of Level Flight, Climb, or Descent, you must follow this sequence: first adjust Thrust, then control the aircraft’s pitch attitude, and finally adjust the trim.

The reason the first step, power adjustment, is so important is that engine Thrust determines the aircraft’s state of ascent or descent. Most people have the impression that a pilot pulls back on the stick to make the plane Climb and pushes forward to make it Descent. In reality, this is a misconception. Pulling back on the stick does indeed cause the aircraft to gain some altitude, but if Thrust remains unchanged, the Airspeed will continuously decrease until the aircraft enters a Stall. Similarly, if you try to force the plane to Descent by pushing the stick forward, the nose will drop continuously, causing Airspeed to increase. This increase in speed generates more Lift, which will actually cause the altitude to rise instead. Therefore, remember: to maintain a stable altitude change, you must adjust Thrust. When transitioning from a Climb to Level Flight (level-off), you must first appropriately reduce engine Thrust; when transitioning from Level Flight to a Climb, increase Thrust; and when transitioning from Level Flight to Descent, reduce Thrust.

If the goal of the second step, adjusting pitch, isn’t to control altitude, then what is it? It is to adjust Airspeed. Pushing the stick forward causes the nose to drop and the speed to increase; pulling back causes the nose to rise and the speed to decrease. Note that this speed adjustment has a limited range. If you need a significant increase in speed, you will ultimately need to increase engine Thrust.

The third step, trim, is mainly to reduce the physical force required to hold the stick. Therefore, once Thrust and attitude are basically stable—that is, once altitude and speed have stabilized—adjust the trim wheel appropriately so the pilot doesn’t have to constantly push or pull on the control stick, relieving the pressure of flying. Keep in mind that trim is an auxiliary operation. Altitude and speed adjustments must rely primarily on Thrust and pitch. Do not over-manipulate the trim.

Practical Exercise Practice

Assume you are in Level Flight at 95 knots, with Thrust at 2200 rpm and an altitude of 2000 feet. You are now preparing to Climb to 3000 feet. The Cessna 172’s best rate of Climb speed is 75 knots, so you first reduce Airspeed by pulling back on the stick to raise the nose. When the speed approaches 75 knots, advance the throttle to 2400 rpm, and the altitude will begin to rise. Meanwhile, to maintain a stable speed, you need to make minor adjustments to pitch. Once the speed stabilizes, trim until the pressure on the control stick is neutral. This establishes a stable Climb phase.

When the altitude approaches 3000 feet, generally speaking, if the rate of Climb is 1000 feet/minute, take 10% of that value—that is, at 2900 feet, 100 feet below your target altitude—push the stick forward to control the aircraft’s attitude back to Level Flight. Simultaneously, the aircraft will accelerate. When speed returns to the Level Flight speed of around 90 knots, reduce the throttle to 2200 rpm. Upon reaching 3000 feet, gradually adjust pitch to stabilize the speed at around 95 knots. Once both altitude and speed have stabilized, perform the final trim. You have now entered a stable Level Flight state at 3000 feet.

To Descent from 3000 feet of Level Flight, with Thrust at 2200 rpm and an Airspeed of 95 knots, down to 2000 feet: First, reduce the throttle to 1800 rpm, pull back slightly on the stick to raise the nose, and adjust the speed to around 85 knots (to manage the Descent speed). Then trim. Once the speed stabilizes, you have entered a stable Descent phase. Upon reaching 2100 feet, advance the throttle to 2200 rpm and push the stick forward to level the aircraft’s attitude back to Level Flight. When the altitude reaches 2000 feet, control to maintain the speed at 95 knots and trim. At this point, you have returned to the stable Level Flight state at 2000 feet.

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