New Stall and Spin Demonstrations: Videos

I just posted several new short videos on my YouTube channel that demonstrate accelerated stalls, incipient spins from stalls, and an intentional spin. The videos, captured during flights in my Extra 300L, show the effects of stalling with coordinated controls and no yaw, stalling while yawing the airplane while turning with “top” and “bottom” rudder, and an intentional spin from a straight-ahead, slow-deceleration stall. I’ve also included a “quiz” video that shows more stalls while turning. See if you can predict which way the stall will break from each of the stalls.

In these videos, I deliberately allowed the stalls to progress to show the effects of misapplied flight controls. If I had applied down-elevator immediately at the first sign of a stall, the departures wouldn’t be apparent. You can’t go wrong following the PARE sequence (described by Rich Stowell) whenever the airplane departs and begins an incipient spin, but if you stop the stall immediately, you regain control of the airplane and can stop a spin from developing. That’s the key takeaway from these videos. At the first sign of a stall or impending departure, unload (relax back pressure and/or apply forward yoke/stick) to keep the stall from progressing. The first instinct of many (most) pilots when a wing drops during a stall is to apply aileron to try to stop the roll, and that action delays recovery and tends to aggravate the stall. In the initial stages of a stall/departure, push first; correct the roll later.

As the Airplane Flying Handbook notes (see “Fundamentals of Stall Recovery” in Chapter 4 on p. 4-4):

First, at the indication of a stall, the pitch attitude and angle of attack must be decreased positively and immediately. Since the basic cause of a stall is always an excessive angle of attack, the cause must first be eliminated by releasing the back-elevator pressure that was necessary to attain that angle of attack or by moving the elevator control forward. This lowers the nose and returns the wing to an effective angle of attack. The amount of elevator control pressure or movement used depends on the design of the airplane, the severity of the stall, and the proximity of the ground. In some airplanes, a moderate movement of the elevator control—perhaps slightly forward of neutral—is enough, while in others a forcible push to the full forward position may be required. An excessive negative load on the wings caused by excessive forward movement of the elevator may impede, rather than hasten, the stall recovery. The object is to reduce the angle of attack but only enough to allow the wing to regain lift.

The FAA also recently published AC 120-109: Stall and Stick Pusher Training (PDF) to clarify and emphasize the proper recovery from stalls. That AC notes in part that:

This AC emphasizes reducing the angle of attack (AOA) at the first indication of a stall as the primary means of approach-to-stall or stall recovery…Stall training should always emphasize reduction of AOA as the most important response when confronted with any stall event.

Core principals of this AC include:

  • Reduction of AOA is the most important response when confronted with a stall event.
  • Evaluation criteria for a recovery from a stall or approach-to-stall that does not mandate a predetermined value for altitude loss and should consider the multitude of external and internal variables which affect the recovery altitude. (Reference: Safety Alerts for Operators (SAFO) 10012, Possible Misinterpretation of the Practical Test Standards (PTS) Language “Minimal Loss of Altitude”).
  • Realistic scenarios that could be encountered in operational conditions including stalls encountered with the autopilot engaged.
  • Pilot training which emphasizes treating an “approach-to-stall” the same as a “full stall,” and execute the stall recovery at the first indication of a stall.
  • Incorporation of stick pusher training into flight training scenarios, if installed on the aircraft.

It’s important to understand how a stall develops into a departure, incipient spin, and then developed spin. You can, for example, see the difference between the type of stall/departure/incipient spin that occurs when you stall out of a yawing turn, and what you see during a deliberate spin from slow-deceleration, wings-level stall. This is why competent stall/spin/upset recovery training is valuable. You need to experience and practice a variety of situations.

You can learn more about stalls and spins in Chapter 4 of the Airplane Flying Handbook and Rich Stowell’s excellent book, Stall/Spin Awareness.

APS also has an excellent article, Cross-Controlled Stalls – The Skidded Turn, available on their website. As APS notes:

The recommended stall recovery (and the one that APS teaches) is: Push – Power – Rudder – Roll – Climb

You’ll also find more information at my website, here and here. Links to many references for pilots and instructors are available on my Aviation Resources page.

Photos from a Formation Flight

For the first time in many months, I participated in a four-ship formation flight earlier this week. A gallery of photos is here. The high-quality photos are by Pat DuLaney, wife of the primary lead (we switched leads, as briefed, halfway through the flight so that I could practice flying both as #4 and later as #2). Some of the pictures are still captured from video that I shot during the flight.

All of the other airplanes are RVs; I’m in my Extra 300L.

To learn more about formation flying, see these articles:

Up Close and Personal: Formation Flying (AvVWeb)
Formation Flying (Plane & Pilot)

I’m flying as #2 behind lead in close trail formation.

Automation Dependency in the Cockpit

Here’s an interesting video from a 1997 presentation to American Airlines pilots. Although directed at airline flight crews, it has much good advice to offer all pilots who use sophisticated avionics in the cockpit.

“Fly Runway Heading”

I have noticed continued confusion among IFR pilots about the instruction to “fly runway heading” during an instrument departure. Many pilots, drawing on their primary training, think they should apply appropriate drift correction to maintain the track of the extended runway centerline. But that’s not what the instruction means or what ATC expects.

First, from the Pilot/Controller Glossary, note the definition of Runway Heading:

RUNWAY HEADING− The magnetic direction that corresponds with the runway centerline extended, not the painted runway number. When cleared to “fly or maintain runway heading,” pilots are expected to fly or maintain the heading that corresponds with the extended centerline of the departure runway. Drift correction shall not be applied; e.g., Runway 4, actual magnetic heading of the runway centerline 044, fly 044.

The same guidance is described on p. 2-35 of the Instrument Procedures Handbook:

Additionally, when required, departure instructions specify the actual heading to be flown after takeoff, as is the case in figure 2-34 under the departure route description, “Climb via heading 112 degrees…” Some existing procedures specify, “Climb runway heading.” Over time, both of these departure instructions will be updated to read, “Climb heading 112 degrees….” Runway Heading is the magnetic direction that corresponds with the runway centerline extended (charted on the AIRPORT DIAGRAM), not the numbers painted on the runway. Pilots cleared to “fly or maintain runway heading” are expected to fly or maintain the published heading that corresponds with the extended centerline of the departure runway (until otherwise instructed by ATC), and are not to apply drift correction; e.g. RWY 11, actual magnetic heading of the runway centerline 112.2 degrees, “fly heading 112 degrees.” In the event of parallel departures this prevents a loss of separation caused by only one aircraft applying a wind drift.

Under VFR, however, you should correct drift to remain over the extended centerline of the runway while on the upwind leg. See, for example, the Airplane Flying Handbook (p. 5-6):

The climb with a wind correction angle should be continued to follow a ground track aligned with the runway direction. However, because the force of a crosswind may vary markedly within a few hundred feet of the ground, frequent checks of actual ground track should be made, and the wind correction adjusted as necessary.

The AFH also calls out drift correction in the “common errors” portion of that section:

Inadequate drift correction after lift-off.

The private pilot and commercial pilot PTS also note this requirement. For example, see item 13 in IV. Takeoffs, Landings, and Go-Arounds of the private pilot PTS:

13. Maintains directional control and proper wind-drift correction throughout the takeoff and climb.

Under IFR, the rationale for flying runway heading and not flying a track (when cleared to “fly runway heading” or “fly heading xxx”) is suggested in the Instrument Procedures Handbook section cited earlier, viz.:

…In the event of parallel departures this prevents a loss of separation caused by only one aircraft applying a wind drift.

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