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Old timers swear aircraft performance can be increased by getting an aircraft "on step" similar to how boats are operated.

enter image description here enter image description here

They claimed a couple extra miles per hour (airspeed was in MPH then) were common. The "step" was alleged to be a "just-right" angle of attack which minimized drag and allowed an airplane to cruise at a higher airspeed than normal on the same power.

Can airplane performance be increased by cruising "on step"?

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    $\begingroup$ This has been repeatedly debunked. Here’s one example: avweb.com/news/airman/184274-1.html $\endgroup$ – JScarry Jul 12 '18 at 3:19
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    $\begingroup$ Performance (here: fuel efficiency) cannot be increased over the theoretical optimum. I believe the “on step” terminology simply refers to, out of two possible trim points on the drag curve, picking the faster one - which is hard to attain when operating close to maximum power. $\endgroup$ – Cpt Reynolds Jul 12 '18 at 11:02
  • $\begingroup$ Wouldn't that require to pull the nose into vacuum, which is not possible, since the border is not really firm and the altitude is far too high? $\endgroup$ – Oleg Lobachev Jul 12 '18 at 16:15
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Remember that in the instance of a boat, you are operating on a relatively dense medium below (water) while passing through a relatively less-dense medium above (air), so it makes sense to minimize resistance by making as little contact as necessary with the denser medium (water). An aircraft is more akin to a submarine than it is to a boat. A submarine, like an aircraft, is surrounded by a medium of relatively constant density at a given depth/altitude, and there is nothing to "get on top of" so to speak, as there is with a boat operating on the surface.

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The Pilot Training Manual For The C-54 Skymaster has this to say about it: enter image description here

The manual is available at Archive.org

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Once you get to Top Of Climb, there are two ways to get the aircraft to the Cruise configuration - the Right Way and the Wrong Way.

The Right Way... set the attitude, wait for the airspeed to reach Cruise Speed, set the power for Cruise Speed, and re-trim during the whole process.

The Wrong Way... set the attitude, set the power for Cruise Speed, wait forever to attain Cruise Speed, and re-trim during the whole process.

If you're using the Wrong Way, then climbing above the Cruise Level and using the subsequent descent to accelerate ("gettting on the step") will appear to work. But it's still Wrong, and it's inefficient.

As with most things in aviation, do it Right first time and every time.

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  • $\begingroup$ This isn't an answer @RAC, the question is can you increase performance, not how you set cruise configuration. This is more of a comment. $\endgroup$ – GdD Jul 12 '18 at 8:52
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    $\begingroup$ @GdD doesn't the second-to-last paragraph answer that? $\endgroup$ – Federico Jul 13 '18 at 17:26

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