Technique: Constant-airspeed climbs
Check and cross-check for this fundamental instrument maneuver
Illustration by Charles Floyd
In VFR flying, instruments are secondary. They confirm and explain what you see, hear, and feel while looking mostly outside. Lose that outside reference, and the instruments—and, hence, an effective instrument scan—become indispensable. Basic attitude instrument flying involves learning to interpret and cross-check instruments, and to respond with the correct control inputs. The same principles apply whether you’re flying straight and level or entering a constant-airspeed climb.
The attitude indicator is central in both the “six-pack” of analog instruments and digital displays because it replaces your critical outside reference. Start here whenever you make any attitude changes. When you’re established in steady-state flight—whether it’s straight and level, climbing, or descending—another instrument becomes the go-to source for fine-tuning control inputs.
Use constant-airspeed climbs for a cruise climb or on climbout to maintain best rate of climb (VY) or best angle of climb (VX) speeds. Constant-rate climbs—where you climb at 500 fpm as you approach your assigned altitude, for instance—require a similar technique, but the vertical speed indicator becomes the primary reference for pitch once established in the climb.
Instrument tips
The four-step scan
Instrument cross-check and the inverted V
Instrument students are commonly taught to scan the instruments using either the control and performance method or the primary/supporting instrument concept. Former Flight Training columnist Ralph Butcher advocated using four steps and an “inverted V” scan.
1. Attitude and power. Look at the attitude indicator and establish the desired attitude, set power by sound, and fine-tune your power setting looking at the tachometer or manifold pressure gauge. Trim coarsely if needed.
2. The inverted V. Scan from the attitude indicator to the turn coordinator, back to the attitude indicator, down to the vertical speed indicator, and back. Butcher calls the turn coordinator and VSI “fine tuners”: The turn coordinator shows a turn before the heading indicator, and the VSI shows a climb or descent before it’s recognizable on the altimeter. This trend information helps you evaluate whether the airplane is behaving as expected.
Instrument errors may be difficult to recognize in instrument conditions, but the inverted V allows you to compare information from different systems. Electrical bank information from the turn coordinator validates vacuum bank information from the attitude indicator, and pitch information comes from both the static-system-driven VSI and vacuum driven attitude indicator. (In glass cockpits, Butcher recommends validating the attitude indicator with the standby attitude indicator.)
3. Scan the primary instruments for pitch, bank, and power.
4. Transition to a circular scan once established, when only small corrections are required. Fine-trim for hands-off flight. —SSD
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