There are several articles written about flying an airplane on the step. The articles I’ll reference are from the past decade and current year, and are valuable contributions to help us better understand flying – in level cruise flight.
In November 2000, Linda Pendleton published “Aviation Myths, Getting on the Step.” She shares a good story about a pilot named Joe, who like other old-timers, would swear to her about a technique that could get a few extra knots out of their Cessna, Cherokee or Mooney. In the article, Linda asks Joe to show her. So, they take off and fly south from Chicago Midway airport over the local farmlands to begin the demonstration.
First attempt, flying on the step
Joe selected a VFR altitude of 3,500 feet MSL for the test. He climbed to 3,800 MSL and leveled the airplane. He then reduced the power to the cruise setting and immediately began a descent. Joe leveled the plane at 3,500 feet and asked Linda to note indicated airspeed.
Second attempt, flying on the step
Joe reduced the power and descended to 2,000 feet. After he established cruise configuration at 2,000 feet, he pushed the throttle in, raised the nose, and began another climb to 3,500. This time, at exactly 3,500 feet MSL, Joe pulled the power back to the cruise setting and pushed the nose over to the level attitude. Joe pointed out that the indicated airspeed was now about 10 miles per hour slower than in the first test. Linda saw the error and proceeded with the third attempt.
Third attempt, flying on the step
They did the test again. This time they climbed to 3,500 feet and pushed the nose over to level attitude. As the plane accelerated they adjusted trim. Finally, when cruise speed was reached, they “reduced the power to the cruise setting, and, voilà,” they saw the same speed Joe had accomplished by flying the plane “onto the step” from above.
Pilot Observations
- Experienced pilots can and do err in establishing best performance for level cruise flight.
- Best cruise performance can be established by flying either from above or below into the selected cruise altitude.
- Linda doesn’t expilcate variables that may affect the setup procedure when climbing into cruise flight from below.
Will the same procedure consistently work when flying from below into cruise or will you need to vary the technique? A Cirrus SR22TN Turbo may require up to 2 minutes at full power to pull the plane into level cruise flight. Here are some variables related to flying a Cirrus SR22 in the flight levels:
- How long should you leave in full power to establish best cruise flight?
- What is the best cruise power setting?
- What cruise speed indication do you watch Knots Indicated Airspeed (KIAS) or True Indicated Airspeed (TAS)?
- Is the setup procedure affected by:
- selected altitude or density altitude?
- airplane weight?
- airplane loading CG?
- aircraft make or type?
- Turbo or normally aspirated?
- What’s the best trim process for the plane?
- Are there other factors to consider? Should you turn a yaw damper on or off?
- Does having the air-conditioning on or off matter?
With Joe’s technique of descending into the selected altitude some of these variables are eliminated.
Okay, I realize a few of these items may not apply to older planes or those flying in single digit altitudes. And, if your plane only shows miles per hour then calculating True Airspeed (TAS) may not be an easy task.
Next week, another article written about flying on the step will be reviewed.
Reference
Pendleton, Linda “Aviation Myths, Getting on the Step,” online AVweb.com/news, November 13, 2000.
Picture insert above right: Flying the Step in a 2008 Cirrus SR22TN-G3 Perspective at flight level 17,500, true airspeed 189 knots, ground speed 194 knots, at 76% power, 2510 RPM, 29.7 manifold pressure at 15.7 gallons per hour, cylinder temps 380 degrees or less, photo credit wikiWings.
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