Straight-and-Level Flight: AFH Chapter 3

Handbook Reference

AFH Ch 3

3.straight-and-level. Straight-and-Level Flight

Straight-and-level flight is the foundation of all airplane control. It is the simultaneous maintenance of a constant heading (no turning) and a constant altitude (no climb or descent). Although it appears static, straight-and-level flight is a continuous process of cross-checking, interpreting, and applying small, smooth control inputs to correct deviations as they begin to develop.

The Two Components

Straight flight — wings held level so the airplane neither banks nor yaws, resulting in a constant heading.
Level flight — pitch attitude held so altitude is constant, with airspeed stabilized for the chosen power setting.

The pilot achieves both by selecting and maintaining a specific pitch attitude and bank attitude relative to the natural horizon, and then verifying the result with the flight instruments.

Use of the Natural Horizon

The primary reference for visual flight is the natural horizon. The pilot establishes a sight picture in which a known portion of the airplane's nose or glareshield rests at a fixed position relative to the horizon for the desired airspeed and power setting. Wings are kept parallel to the horizon to maintain straight flight. Because pilot eye height varies between airplanes and even between pilots in the same airplane, this sight picture must be learned in each airplane.

The instruments — attitude indicator, heading indicator, altimeter, vertical speed indicator (VSI), and airspeed indicator — confirm what the pilot sees outside. Roughly 90 percent of the pilot's attention should remain outside the cockpit, with brief interior scans to verify performance.

Pitch Control

Pitch attitude controls the airplane's vertical path. In stable, level flight at a constant power setting, a fixed pitch attitude produces a constant altitude and airspeed. Corrections are small:

If the altimeter shows a climb, lower the nose slightly until the altimeter stops, then re-trim.
If the altimeter shows a descent, raise the nose slightly, verify the altimeter has stopped, then re-trim.
Use the VSI as a trend instrument — it shows the rate of deviation before the altimeter does.

A common rule of thumb: for deviations of less than 100 feet, correct with pitch alone; for larger deviations, also adjust power.

Bank Control

Bank attitude controls heading. Wings level produces a constant heading; even a small bank, left uncorrected, becomes a turn. Cross-check the heading indicator, attitude indicator, and turn coordinator along with the visible horizon. Correct heading drift with coordinated aileron and rudder inputs to roll the wings level, then neutralize the controls.

Yaw Control and Coordination

The rudder keeps the airplane coordinated, not pointed. Use the inclinometer (ball) as the reference: step on the ball to center it. In a properly trimmed airplane in straight-and-level flight, only a small amount of right rudder is typically needed at cruise power to offset the left-turning tendencies (torque, P-factor, spiraling slipstream, gyroscopic precession).

Trim

Proper trim technique removes control pressures so the airplane will hold attitude hands-off, or nearly so. Sequence:

Establish the desired pitch attitude with elevator pressure.
Hold that attitude until airspeed and altitude stabilize.
Trim off the elevator pressure.
Repeat for any rudder pressure (in airplanes equipped with rudder trim).

A properly trimmed airplane reduces workload, improves scan, and makes deviations easier to detect because the airplane no longer requires a continuous control force.

Common Errors

Fixating on a single instrument instead of cross-checking.
Spending too much time looking inside; loss of outside reference allows attitude to drift.
Using the elevator alone to correct heading, or the rudder alone to correct altitude.
Failing to retrim after each pitch or power change, resulting in a constant control pressure that masks deviations.
Chasing the altimeter or VSI with large, abrupt control inputs that overshoot in the opposite direction ("PIO" — pilot-induced oscillation).
Allowing one wing to ride low because of an uneven fuel load or relaxed grip on the yoke.

Example Cross-Check

At cruise, the scan flows roughly: horizon (wings level, nose attitude) → altimeter → horizon → heading indicator → horizon → airspeed → horizon → VSI → horizon. Each interior glance is short — about one second — and the pilot returns to the horizon between each instrument. The pilot is looking for trends, not absolute readings, and corrects each trend before it becomes a noticeable deviation.

Mastery of straight-and-level flight is a prerequisite to every other maneuver, because climbs, descents, and turns are all departures from, and returns to, this baseline condition.

Oral Exam Questions a DPE Might Ask

Q1What is your primary reference for maintaining straight-and-level flight in VMC?

The natural horizon. I set a sight picture with the nose and wings against the horizon for the desired airspeed, then use the flight instruments to verify the airplane is actually holding altitude and heading.

Q2Why does an airplane in cruise require right rudder to stay coordinated?

Because of the four left-turning tendencies — torque, P-factor, spiraling slipstream, and gyroscopic precession — which all yaw the nose left at typical cruise power. A small amount of right rudder, or rudder trim if equipped, centers the ball.

Q3If you're 50 feet low, how do you correct, and when would you also use power?

For deviations under about 100 feet I correct with pitch alone — raise the nose slightly, let the altimeter stop, then re-trim. For larger deviations or when airspeed is also off, I add power along with the pitch change so I can recover altitude without bleeding off airspeed.