Understanding Pitch and Power

Classic Aviation Controversy Made Easy!

By: David St. George, ATP, MCFI, DPE

     Any glider pilot will tell you how to control airspeed; to go slower, raise the nose and conversely, lower it for more speed.Set an outside pitch reference then verify this with a glance inside at the gauge. I fly and teach in gliders and use this same approach to power planes. The throttle allows the privilege of climbing (which is more difficult in gliders) and the pitch for each airspeed will be different depending on the power setting. The energy management issue gets confusing when you have an engine and chemical energy at your disposal. It sure can seem "just like a car," e.g. add power to go faster (and this works to a point.) The most important reason not to think in this manner is due to the unreliability of this premise. It is true that full power will give you the fastest speed available in an aircraft. Unfortunately, full power will also allow you to fly the slowest speed in an aircraft! That is where the real problem lies. As you fly slower (the critical phases of flight) mishandling pitch and power can get you in trouble fast. In his classic book Stick and Rudder, Wolfgang Langewiesche cautions: "Get rid at the outset of the idea that the airplane is only an air-going sort of automobile. It isn't...it goes on wings...And a wing is an odd thing, strangely behaved, hard to understand, tricky to handle. In many important respects, a wing's behavior is exactly contrary to common sense." (see the Barry Schiff article below "Fatal Instinct") He goes on the explain the need for overcoming "human instincts" and trusting instead to trained responses. Langewiesche spends a lot of time explaining angle of attack (the true secret here in the pitch/power controversy). This web site is not intended to teach aerodynamics but I do caution pilots and CFIs who have not thought carefully on these issues to study this area of flight carefully or you will be forever unsafe and unconfident. The aircraft will act in ways you will not understand. If you study and learn applied aerodynamics, you will be forever grateful and at ease in the air. Advisory Circular 61-50A in the table is ancient...from the 1970s (before the FAA withdrew from this controversy and weaseled into half truths). Since it has neither been cancelled or superceded, I consider it still valid and in force. The other references are from aviation writers across the whole spectrum of aviation.

Barry Schiff: "Pitch and Power" Barry Schiff: "Fatal Instinct" John Denker (web site) Aerodynamic For Naval Aviators AC 61-50A (pdf)
AC-61-50A (Web)
FAA: Stalls and Spins
This is a
great analysis!
Rich Stowell Sparky Imeson

     You probably figured by now I come down on the "pitch for airspeed" side of this discussion (a.k.a., "the Navy Method"). If you did have an F-16, you can make airspeed in just about any direction (AF: power for airspeed). There is however a great video online of a Thunderbird messing this up in a dramatic fashion. Check this link for what I call "the perfect stall". This poor guy is probably flying a desk now at the Pentagon with a sign hung around his neck pointing out why AOA is an unforgiving and immutable aerodynamic principle. He dramatically demonstrated you can even stall a superb aircraft like the F-16 if you mishandle angle of attack. Notice that if you freeze this video as the ground comes into view, you cannot determine AOA...it looks like a "fly by" picture. Only in motion can you determine AOA. Similarly, if you are on final to a runway the single "snapshot" is largely useless, we must carefully monitor "trend" (the picture as it changes over time). This is one reason that a very disciplined outside view is necessary for reliable aircraft control. The flight instruments should be consulted very briefly and only to verify the performance (not change it).

     Every serious aerodynamics source is consistent on this point of pitching for AOA and hence airspeed. It is true that it is more psychologically difficult to initially learn to fly this way (this area of flying is seriously "counter-intuitive). If we were just flying the Toyota of the sky and powered down the glide slope life would be more consistent. Cessna has for years put "steering wheels" in their planes and also once encouraged people to "drive in the sky" to sell planes and the ease of flight training. As it turns out, avoiding this common negative transfer from automobiles is one of our greatest challenges in learning to fly correctly. Time spend analyzing and internalizing the correct aerodynamic mental model is essential to safety. If you are low and slow on final and mistakenly "pitch for altitude and power for airspeed" you will just climb the induced drag side of the power curve and end up a statistic. Easing up on the yoke to maintain airspeed and adding power (along with right rudder) to maintain or regain altitude, will bring you back to a stabilized glide path. I highly recommend Rich Stowell's book Emergency Maneuver Training for a thorough review of aerodynamics in a very understandable fashion and his new Stall/Spin Awareness as a perfect advanced level text. His articles, linked on his web site, are super. Pursue accuracy in your knowledge and precision in your flying!