Airplane Climbs

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Many of the same reference points used in straight-and-level flight can be used for climbs. Reference to wingtips may be used to complement instrument indications for laterally level flight and can also be used for pitch information.

In some aircraft, the forward field of view is limited while climbing, making frequent reference to the flight instruments rather important for directional control. However, lateral references may still be used for directional orientation after a bit of practice.

Let’s say we’re cruising along at 3000 feet above ground level (AGL), and we are asked by air traffic control to climb to 5000 feet. To initiate the climb you will do two things: First, add power as recommended by the aircraft’s manufacturer. This will vary from plane to plane, but for many aircraft, climb settings normally are full power. Then increase backpressure on the control yoke, raising the nose of the plane. There are two airspeeds that you will be concerned with during climbs: the best angle of climb airspeed and the best rate of climb airspeed.

The best rate of climb, expressed as Vy, gives you the greatest gain in altitude over a period of time. The best angle of climb airspeed, known as Vx, results in the greatest altitude gain in a given distance. Generally, for takeoffs you will initially climb at Vx airspeeds for that plane. For climbs from a given altitude, such as in our example, many aircraft manufacturers recommend using the Vy airspeed. For most airplanes, Vx is a lower airspeed than Vy. As a result, the angle of attack is greater at Vx than it is at Vy, resulting in the nose of the plane being higher.

As you raise the nose, the airspeed will begin to fall. You are now taking some of the additional power and lift and converting it to an altitude gain. Normally you will want the airspeed to stabilize at the correct climb airspeed, whether that is Vx, Vy, or another airspeed recommended by the manufacturer. Once the airspeed has stabilized, you can retrim the elevator to reduce backpressure on the control yoke to neutral.

As you approach the altitude you are climbing to, you will need to gradually reduce the nose-up angle. Correctly done, you will level off at the altitude you are supposed to attain. This is where the vertical speed indicator (VSI) comes in handy in helping you judge when to begin the level off. A rule of thumb is to begin leveling off the plane when you are 10 percent of the VSI’s reading below the desire altitude. Let’s say we’re climbing at 500 feet per minute and want to level off at 3000 feet. Ten percent of 500 feet per minute is 50. In this case, at 2950 feet we would start to level off, hopefully ending up at 3000 feet as the final altitude. If we were climbing at 1000 feet per minute, we would start to level off at 2900 feet.

When releasing backpressure on the control yoke, the input should be gradual. You don’t want to force your passengers up against their seatbelts by shoving the control yoke forward too forcefully, giving them the feeling of weightlessness. Normally, a nice, steady release of the backpressure on the control yoke gives your passengers a pleasant transition from the climb to level flight. Once you are in level flight, you will need to reset your engine power, then retrim the elevators for level flight.

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