Stalls at “Any Attitude, Any Airspeed”

Every pilot learns that a wing can stall “in any attitude and at any airspeed.”

But it’s difficult to demonstrate that principle in a typical training aircraft. This video of an exercise that I do with my stall/spin/upset recovery students shows the value of training in an aerobatic aircraft.

I fly a basic loop, but at several points during the maneuver, I intentionally increase the angle of attack by pulling back abruptly on the stick. Each time I pull, the angle of attack quickly reaches the critical angle of attack, and the airplane shudders in an accelerated stall, regardless of the airplane’s airspeed or pitch attitude relative to the horizon.

In other words, you can change the airplane’s attitude (and its angle of attack) almost instantly, but changing its flight path requires more time. That difference between the attitude and the flight path is angle of attack, and when that angle exceeds the wing’s critical angle of attack, the wing stalls.

It’s also helpful to remember that a loop is just a vertical turn. The same principle applies when you bank the wings and turn an airplane in the horizontal plane. If you pull back on the yoke or stick during a turn, you increase the angle of attack. Pull back too aggressively, and the wing will reach its critical angle of attack and stall, regardless of the indicated airspeed.

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Landing at Yerrington, NV (O43)

I landed the A36 at Yerrington, NV (O43) for fuel on the way home from Las Vegas. Yerrington is a good fuel stop in the Reno area. Relatively inexpensive self-serve avgas and a pilot’s lounge. A strip mall is a short walk away if you need food or other supplies.

A Dose of Vitamin G

I practiced a series of basic aerobatic maneuvers on this flight out of Boulder City, NV (KBVU). I’d been busy working with instrument students in Seattle, so I needed to refresh my G tolerance and get ready for summer aerobatic flights. Keen observers will note lots of bobbles and other flaws. But it was fun to be back in the Extra 300L, which is a thoroughbred.

I mounted one camera so that you can see the control stick in the front cockpit. Note how little the stick has to move during basic maneuvers–only a slight deflection of the ailerons and elevator is required to achieve large effects.

 

Videos: Quick Takes on Aerobatics

I recently created several short videos that highlight specific aerobatic maneuvers that I demonstrate during rides and instruction in the Extra 300L. Here are few; you can find more at my YouTube channel, BruceAirFlying.

To learn more about making aviation videos, see Aviation Video Tips.

Hammerhead

Slow Roll

Four-Point and Aileron Rolls

Inverted Flight

Accelerated (Turning) Stalls in a Bonanza

Many pilots are uncomfortable with stalls while the wings are banked, typically because they’re concerned that, at the stall, a wing will drop, and the airplane will depart into an incipient spin. In this video, I demonstrate stalls in an A36 Bonanza while banking at 45 and 30 degrees. As you can see, if the turn is coordinated, at the stall, the nose drops toward the horizon, but the bank angle remains essentially constant.

Because the airplane is turning, the stall occurs at an airspeed higher than it does in a straight-ahead, wings-level stall. An airplane in a level turn is accelerating (changing velocity because it’s changing direction), and therefore experiences more than 1G.

As the Airplane Flying Handbook notes:

The airplane will, however, stall at a higher indicated airspeed when excessive maneuvering loads are imposed by steep turns, pull-ups, or other abrupt changes in its flight path. Stalls entered from such flight situations are called “accelerated maneuver stalls,” a term, which has no reference to the airspeeds involved. (Chapter 4: “Slow Flight, Stalls, and Spins”)

In non-aerobatic aircraft like the Bonanza, we typically practice accelerated stalls while turning. As I explain, the first step in any stall recovery is reducing angle attack. After the wings are flying again, you can correct the bank and return normal flight.

To learn more about accelerated stalls, see other videos on my YouTube channel, including Accelerated Stalls from Steep Banks and Accelerated Stalls in the Vertical.

Accelerated Stalls in a Bonanza

Recovery from Inverted/Overbank Attitudes

Here’s an exercise I do with students in my stall/spin/upset recovery courses. It demonstrates the importance of proper recovery–rolling back to upright flight–from an overbank or inverted attitude. Many pilots instinctively try to pull their way back to the horizon, a maneuver that typically leads to excessive airspeed, high Gs, and significant loss of altitude. More information is available at my website, here.

Accelerated Stalls in the Vertical

Pilots know that you can stall the wing at any airspeed and in any flight attitude. A stall is all about angle of attack. But it’s hard to demonstrate the concept in a typical normal-category airplane. In this video, I show a series of accelerated stalls during loops in the Extra 300L. As you can see, I can change the aircraft’s attitude almost instantly while the airplane continues along its flight path, creating a large angle of attack, and therefore, an aerodynamic stall, even when the airplane is nose-low relative to the horizon and flying well above the normal stall speed.