Turning by reference to instruments means changing the airplane's heading without relying on the outside horizon. The pilot uses the attitude indicator to control pitch and bank, then checks the other flight instruments to maintain the desired altitude, airspeed, and rate of turn.
In this lesson, you will learn to make standard-rate turns (rate one turns) using flight instruments. You will practice entering a turn, maintaining the correct rate, keeping altitude and airspeed steady, and rolling out accurately on the selected heading.
This lesson builds on the basic principles explained in our Turns lesson. Here, the focus is on instrument indications and cross-check, rather than visual references.
Learn to establish and maintain a coordinated standard-rate turn by reference to instruments. Use a systematic instrument cross-check to control bank, altitude, and airspeed, then roll out smoothly on the selected heading.
Establish the required bank using the attitude indicator and confirm the turn rate with the turn coordinator.
Monitor altitude, airspeed, heading, and turn rate. Recognize deviations and make small, coordinated corrections.
Anticipate the selected heading, smoothly return to wings-level flight, and confirm that the turn has stopped.
Understanding Standard-Rate Turns
In instrument flying, turns are often made at a specific rate rather than a fixed bank angle. The most common reference is the standard-rate turn, also called a rate one turn.
A standard-rate turn changes the airplane's heading at a rate of 3 degrees per second. The same rate applies whether the airplane is turning left or right.
At a constant standard rate, a full 360° turn takes 120 seconds. A 90° heading change takes 30 seconds, while a 180° change takes 60 seconds.
This diagram shows how much the heading changes when the airplane maintains a constant turn rate of 3° per second.
- 0 sec 0°
- 30 sec 90°
- 60 sec 180°
- 90 sec 270°
- 120 sec 360°
How Airspeed Affects the Required Bank Angle
A standard-rate turn always has the same rate of 3° per second, but it does not require the same bank angle at every airspeed.
At a higher true airspeed, the airplane needs a greater bank angle to maintain the same rate of turn. At a lower true airspeed, less bank is required.
A useful rule of thumb for estimating the required bank angle is to use 15 percent of true airspeed (TAS).
At a true airspeed of 120 kt, divide the speed by 10, then add half of that result.
120 ÷ 10 = 12 12 + 6 = 18°The approximate bank angle for a standard-rate turn is therefore 18°.
Here are a few additional examples using the same rule of thumb:
| True Airspeed | Approximate Bank Angle |
|---|---|
| 80 kt | 12° |
| 100 kt | 15° |
| 120 kt | 18° |
| 140 kt | 21° |
The calculated bank angle is only an initial estimate. It does not guarantee a turn rate of exactly 3° per second.
Use the actual turn-rate indication to confirm the rate of turn. Also remember that the calculation uses true airspeed (TAS), not groundspeed.
Instrument Cross-Check During a Turn
During an instrument flying turn, the pilot must monitor more than the bank attitude. The airplane must maintain the selected altitude and airspeed while turning at the desired rate.
The attitude indicator provides a direct reference for pitch and bank. The other flight instruments show whether the airplane is maintaining the intended flight condition. A continuous instrument cross-check helps the pilot recognize and correct deviations early.
Primary and Supporting Instruments
During a stabilized, level standard-rate turn at constant airspeed, three instruments provide the main performance references. Other instruments help the pilot interpret and confirm those indications.
Use this reference diagram to understand which instruments deserve particular attention during a stabilized turn.
Primary for pitch. The altitude should remain constant during a level turn. Any developing change indicates that pitch control needs attention.
Primary for bank performance. The miniature aircraft indicates the rate of turn. In a stabilized turn, its standard-rate mark helps the pilot maintain the selected turning rate.
Primary for power performance. The indicated airspeed should remain at the selected value. An increasing or decreasing airspeed calls for further cross-check.
Shows pitch and bank attitude. It provides the direct reference for setting and adjusting the airplane's attitude. It does not measure the actual rate of turn.
Shows the airplane's changing heading and progress toward the selected heading. It indicates heading, not bank angle or instantaneous turn rate.
Provides an additional indication of altitude performance. In a level turn, vertical speed should be near zero. A conventional VSI responds with some delay.
Check the inclinometer ball to detect a slip or skid. A centered ball indicates coordinated flight.
Check the tachometer or manifold pressure gauge, as applicable, to confirm the selected power setting.
Interpreting the Instrument Indications
A single instrument rarely tells the whole story. The pilot should compare related indications before making a correction.
For example, the turn coordinator may indicate the correct turn rate while the airplane slowly loses altitude. The bank performance is correct, but the airplane is not maintaining level flight.
You are maintaining a constant-airspeed, standard-rate turn. During the instrument cross-check, you observe:
The airplane is turning at the desired rate and maintaining airspeed, but it is descending. The altimeter and VSI indicate a pitch-performance problem, not a turn-rate problem.
Use the attitude indicator to make a small pitch correction, then confirm that the altitude trend improves. Continue checking airspeed and turn rate while correcting the deviation.
How to Fly a Standard-Rate Turn — Step by Step
During an instrument turn, the pilot's attention must shift as the airplane moves from straight-and-level flight into an established turn. The instrument used to set an attitude is not always the instrument used to confirm the resulting performance.
Follow the instrument references below for a level, constant-airspeed standard-rate turn in a light training airplane. Look first identifies the main reference for that phase, not an instrument to stare at. Maintain a continuous cross-check throughout the maneuver.
Entering and Establishing the Turn
Note the current heading on the heading indicator and identify the heading you want to reach. Confirm the selected altitude on the altimeter and the airspeed on the ASI. The AI should show a wings-level attitude, while the TC should confirm that no turn is developing.
Watch the bank scale on the AI as you smoothly roll toward the estimated bank angle. Check the ALT and VSI for the first signs of an altitude change. Use the AI to make a small pitch adjustment as needed to maintain level flight.
Glance at the TC to confirm the direction and development of the turn, and check the ball for coordination. Monitor the ASI for a developing speed change. During roll-in, do not use a momentary TC indication as though the turn were already stabilized.
Once the bank has stabilized, check whether the miniature aircraft on the TC indicates the standard-rate mark. If the turn rate is not correct, make a small bank adjustment using the AI, then confirm the result on the TC.
Check the ALT for level-flight performance and the ASI for constant airspeed. Adjust pitch and power as necessary, confirming power changes with the tachometer or manifold pressure gauge, as applicable. Recheck the TC after each adjustment.
Maintaining the Turn and Correcting Deviations
Use the ALT to confirm that altitude remains steady. Use the TC to confirm the selected turn rate. Use the ASI to confirm that airspeed remains at the selected value.
Return frequently to the AI to check the actual pitch and bank attitude. Include the HI in your scan to monitor progress toward the selected heading. Check the VSI for an altitude trend and the ball for coordination.
Repeat this pattern while incorporating HI, VSI, the inclinometer ball, and power instruments. This is an example, not a rigid scan order. Do not fixate on one instrument.
If the TC shows an incorrect turn rate, use the AI to change the bank slightly, then recheck the TC.
If the ALT shows an altitude deviation, use the AI to correct the pitch attitude. Check the VSI for the trend and monitor the ASI while altitude is restored.
If the ASI shows an airspeed deviation, cross-check pitch and altitude before changing power. Confirm any power adjustment with the engine instruments, then verify its effect on airspeed.
Make small corrections and allow the indications to respond. Keep all three performance references in the scan rather than correcting one parameter at the expense of another.
You are established in a right standard-rate turn, maintaining 4,000 feet and 95 KIAS. Your instrument scan shows:
1. TC: Identify the insufficient right-turn rate.
2. AI: Increase the right bank slightly using coordinated controls.
3. TC: Allow the new turn rate to stabilize, then confirm that the indication has moved toward the standard-rate mark.
4. ALT and ASI: Confirm that altitude and airspeed remain steady. Make a small pitch or power adjustment only if the indications require it.
Rolling Out on the Selected Heading
A turn does not stop immediately when the pilot begins to level the wings. The airplane continues changing heading while the bank angle decreases.
To finish an instrument turn accurately, begin the rollout before reaching the selected heading. Use the heading indicator to identify the rollout point, then shift attention to the attitude indicator to control the return to wings-level flight.
Anticipating the Rollout
A useful starting rule is to begin the rollout approximately half the bank angle before the selected heading.
This is an initial estimate, not a fixed procedure for every airplane. The exact lead depends on the bank angle, the turn rate, and how quickly the pilot rolls the wings level.
Use this estimate to determine when to begin reducing the bank. Refine the lead through practice in your aircraft.
With an established right bank of 18°, begin rolling out when the HI reads approximately 171°.
The following example shows the final part of a right turn from heading 090° toward heading 180°.
Completing the Rollout — Step by Step
The key is to change your instrument priorities as the airplane transitions from a stabilized turn back to straight-and-level flight.
Continue monitoring the heading indicator as the selected heading approaches. In the example above, watch for the HI to reach approximately 171°.
Until that point, maintain the established turn rate using the TC, with the AI supporting bank control. Briefly check the ALT and ASI to confirm that altitude and airspeed remain stable.
At the rollout point, shift your main bank reference from the TC to the AI. Apply smooth, coordinated aileron and rudder pressures opposite the direction of the turn.
Watch the AI bank indication decrease steadily toward zero. Aim for a rollout rate similar to the rate used during roll-in.
As bank decreases, gradually reduce any additional elevator back pressure used during the turn, as required to maintain altitude. Check the ALT for pitch performance and the ASI for airspeed changes.
The TC should show the turn rate decreasing. Do not chase a momentary TC indication while the airplane is rolling.
As the AI approaches a wings-level indication, check the HI frequently. The heading should be approaching the selected value.
Complete the rollout so that the AI shows wings level as the HI reaches the selected heading. In our example, the desired indication is 180°.
Check the TC for a stopped turn and the ALT and VSI for level-flight performance. If the heading is still changing, the airplane has not yet established stable straight flight.
HI: The selected heading remains steady.
AI: The wings are level, with the pitch attitude appropriate for straight flight.
TC: No continuing turn is indicated.
ALT and VSI: Altitude is maintained and vertical speed settles near zero.
ASI: The selected airspeed remains steady.
If necessary, make small pitch or power corrections and retrim the airplane after it has stabilized.
Correcting Heading Errors After the Rollout
Even with good anticipation, the airplane may finish slightly before or beyond the selected heading. Use the HI to identify the deviation and make a smooth correction.
The HI passes beyond the selected heading before the turn stops.
Establish a controlled wings-level attitude, then use a small, coordinated turn in the opposite direction to correct the heading. Confirm the correction with the HI.
The airplane stops turning before reaching the selected heading.
Use a small, coordinated bank toward the desired heading. Monitor the HI and return to wings level as the heading is captured.
Instrument Turn Practice and Review Questions
These exercises test your ability to interpret flight instruments during a standard-rate turn. For each situation, identify the instrument that deserves your attention and decide what action is appropriate.
Read the instrument indications, decide what you would do, and then open the explanation to check your reasoning.
Practice: Interpret the Instrument Indications
You have just started rolling into a left turn at 100 KIAS. The airplane is still changing its bank angle.
| AI | Left bank increasing toward 12° |
|---|---|
| TC | Turn indication moving toward the standard-rate mark |
| ALT | 3,500 ft, steady |
| VSI | Near zero |
| ASI | 100 KIAS, steady |
- Which instrument should guide your bank control during this phase?
- Should you immediately chase the TC indication?
- When does the TC become the main turn-rate reference?
Show Explanation
1. Focus on the AI. During roll-in, use the attitude indicator to establish the intended bank smoothly.
2. Do not chase a transient TC indication. The turn coordinator responds to the developing turn and roll motion. Maintain the cross-check, especially ALT and ASI.
3. Once the bank and turn rate stabilize, use the TC as the primary bank-performance reference. Check the AI for the attitude needed to maintain that rate.
You are established in a level standard-rate turn at 4,000 feet. The selected airspeed is 105 KIAS.
| TC | Standard-rate indication steady |
|---|---|
| ALT | 4,000 ft, steady |
| ASI | Decreasing from 105 to 99 KIAS |
| AI | Pitch and bank attitudes approximately unchanged |
| RPM | Decreased from 2,300 to 2,200 RPM |
- Which flight parameter is deviating?
- Which instruments help identify the cause?
- What adjustment would you make and what would you check afterward?
Show Explanation
1. Airspeed is decreasing. The ASI shows the deviation, while altitude and turn rate remain steady.
2. Check the engine instruments and AI. The lower RPM is consistent with a reduction in power. The steady attitude and altitude help you interpret the airspeed trend.
3. Restore the appropriate power setting for the selected airspeed, making any necessary aircraft-specific adjustment. Confirm the power change on the engine instruments. Then verify that the ASI approaches the selected airspeed while ALT and TC remain stable.
As airspeed changes, the bank angle needed for a given turn rate may also change. Continue monitoring the TC rather than assuming that the original bank will always remain correct.
You are turning left toward heading 270°. Your airplane is holding a 16° left bank, and the selected heading is approaching.
| HI | 278°, decreasing toward 270° |
|---|---|
| AI | 16° left bank |
| TC | Standard-rate left turn |
| ALT | Steady |
| ASI | Steady |
- Has the airplane reached the approximate rollout point?
- Which instrument now becomes the primary bank reference?
- Which indications confirm a successful rollout?
Show Explanation
1. Yes. Using the half-bank-angle rule of thumb: 16° ÷ 2 = 8°. For this left turn, 270° + 8° = 278°. Begin the rollout at approximately 278°.
2. Focus on the AI. Smoothly reduce the left bank toward wings level, while checking the HI frequently as it approaches the selected heading.
3. Confirm the final indications. The AI shows wings level, the HI remains near 270°, and the TC indicates that the turn has stopped. Check ALT and ASI to confirm that level, constant-airspeed flight has been reestablished.
The calculated rollout point is an estimate. Actual lead depends on the airplane and rollout technique.
Review Questions
Answer the following questions before opening the explanations. Concentrate on instrument priorities, interpretation, and cross-check.
01 Which instrument guides bank during the initial roll-in to a standard-rate turn?
The attitude indicator (AI). Use it to establish the approximate bank angle, then confirm the resulting turn rate on the TC as the turn stabilizes.
02 Which instrument is primary for maintaining bank performance during a stabilized standard-rate turn?
The turn coordinator (TC) is the primary reference for maintaining the selected turn rate. The AI supports bank control.
03 During a level turn, which instrument is primary for pitch performance?
The altimeter (ALT). It confirms whether altitude is being maintained. The AI helps you make pitch-attitude corrections, and the VSI supports the altitude trend.
04 What is the primary power-performance instrument during a constant-airspeed, stabilized standard-rate turn?
The airspeed indicator (ASI). Engine instruments, such as the tachometer or manifold pressure gauge, support power control. Always interpret airspeed together with pitch and altitude indications.
05 Why does the heading indicator continue changing during a correctly established turn?
Because the airplane is intentionally changing its heading. The HI shows heading progress, while the TC shows the turn rate. A changing HI indication is expected during the turn.
06 What does an off-center inclinometer ball indicate?
It indicates uncoordinated flight, either a slip or a skid. Use appropriate coordinated rudder control to center the ball while maintaining the desired attitude and turn rate.
07 Why should you avoid relying only on the VSI to detect an altitude deviation?
A conventional VSI responds with some delay. Use the ALT as the primary reference for maintaining altitude and the VSI as a supporting indication of the vertical trend.
08 How do the instrument priorities change when rolling out of a standard-rate turn?
Use the HI to anticipate the rollout. During the return to wings-level flight, the AI becomes the primary bank-attitude reference. Once straight flight is established, the HI becomes the primary heading reference. Continue checking ALT, ASI, and TC.
