Do you find it hard to level off precisely on altitude? Have you noticed it sometimes takes a long time for the airplane to accelerate to cruise speed as you level off, and that it tends to climb as you accelerate? Are you concerned about the safety (and legal) implications of an “altitude bust”?
A lot happens during the short time of a transition from climb into level flight. Time it wrong and you’ll be imprecise with your altitude (or miss it altogether). Manage attitude and power incorrectly and you’ll delay the time it takes to reach your planned airspeed. Even if you’re using an autopilot with altitude preselect, the wrong technique can cause you to miss altitude and performance.
Do everything right, however, and you’ll level off exactly on target, and quickly reach your airspeed goal—every time.
Precision Level-Off. If you think “level off at 6,000 feet” means “climb to 6,000 feet, then level off,” you will blast through your altitude, especially in more powerful or more aerodynamically clean airplanes. To precisely capture altitude and rapidly reach cruise speed as you level off, begin the process well before your desired (or assigned) altitude.
Altitude callouts are a staple in two-pilot airplanes, and can help you when flying alone as well. “Four thousand five hundred climbing to 7,000; 2,500 hundred feet to go” is completely unambiguous and does much to keep you in the loop as the airplane climbs. Say it out loud—your passengers won’t mind; they may even think more of you as a “professional” pilot.
The real trick to a precision level-off, however, is to begin the process at least 500 feet before your final altitude. If your airplane is climbing at more than 500 feet per minute, lower the pitch to limit vertical speed to 500 fpm. This gives you a full minute to work the transition. It also causes the airplane to begin accelerating toward cruise speed, requiring you to trim the nose down slightly to hold vertical speed. You’ll reduce the climb rate, begin accelerating to cruise, and make a small trim change now to avoid a larger trim change later—all promoting your goals of precision and rapid acceleration.
But you’re not done with your pre-altitude work yet. As you get within 200 feet of leveling off, lower the nose a little more, trim accordingly, and—if your airplane is so equipped—close the cowl flaps. Cowl flaps are used to create additional airflow across the engine for cooling at low indicated airspeeds, such as climb. This extra airflow creates significant “cooling drag,” however, so open cowl flaps rob you of acceleration you’d get in a more streamlined condition. Close them at this point, just before leveling off, and the airplane will accelerate more rapidly to cruise speed. Forget the cowl flaps, on the other hand, and in some high-performance airplanes you may loose five knots or more from cruise-flight true airspeed.
Reaching Altitude. Now you’re ready to ease the nose over precisely onto your altitude. Leave cruise-climb power set for a moment, so your airplane speeds up more rapidly. As you reach your expected cruise speed, reduce power as needed for cruise. Once everything is stable run your Cruise checklist.
As it accelerates the aircraft will continue to pitch upward (trying to seek its slower, trimmed airspeed), so you’ll need to gradually trim the nose further downward until it’s trimmed for cruise flight. If you’ve made a gradual transition, however, beginning at 500 feet before level-off and moderated at 200 feet below final altitude, this trim change will be minimal, and you’ll much more easily transition precisely to your desired altitude.
Autopilot Operation. If your airplane is equipped with an altitude-capture autopilot (and you’ve programmed it correctly), you may think you can sit back and let it do its thing. Don’t get too complacent, however. You can delegate the actual flying to automation, but history shows it’s a bad idea to ignore monitoring and abdicate pilot-in-command responsibility to the autopilot. Use the same techniques discussed for hand-flying a level-off: Moderate the climb rate, watch the autopilot adjust trim, and clean up and power down for cruise at the same places. Be immediately ready to disengage the autopilot and take over by hand if for any reason it does not appear to be doing precisely what you want it to do.
Leveling off from climb to cruise is easy; we do it on our first flying lesson. But transitioning to cruise precisely, while rapidly and efficiently accelerating to cruise speed, takes a more refined single-pilot technique.
Sterile cockpit rule
To reduce workload and facilitate precision, airline pilots are required to maintain a “sterile cockpit” in certain phases of flight. A sterile cockpit is one where unnecessary conversation and activities are prohibited, allowing the crew (in this case, you) to focus solely on what it takes to fly the airplane. There’s no reason you can’t be as safe and precise just because you’re not being paid to fly.
Within 1,000 feet of a level-off altitude, invoke your own sterile cockpit rule. Ask your passengers to delay any questions or conversation until you’ve completed the level-off. Don’t worry about tuning navigation devices, folding maps, or any other cockpit chores until established and trimmed on your new altitude. Delay calling Flight Watch, or manipulating the fuel mixture, or accessing a weather uplink until your transition is complete. Transmit on the radio only if asked by air traffic control.
By focusing your attention on what’s immediately necessary to make the transition to level flight, you’ll be far more precise, and much less likely to “bust” an altitude or miss an autopilot error that prevents an accurate altitude capture.
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