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Secondary Stall Demonstration

A secondary stall is the one you cause yourself, in the seconds after you thought you had the first one fixed. Instructors demonstrate it on purpose, at altitude, so a student meets that mistake with a CFI aboard rather than for the first time near the ground.

Slow Flight, Stalls and Spins — FI.X.H

Why this demonstration exists

Almost every stall you have practiced was arranged in advance: wings level, a configuration you chose, an altitude you picked, a plan to recover. The real world does not set stalls up that way, and knowing how to handle the ones it hands you is what keeps you and your student alive.

Here is the scenario this demonstration is built around. The engine has quit and you are gliding to a field that is starting to look short, so you pull to stretch the glide and the airplane stalls. You get the nose down, the buffet stops, and with the ground filling the windshield you pull again — too soon and too hard. It stalls a second time, lower than the first, with less altitude left to trade. That second stall is the one you caused, and it is the one that finishes the accident.

This is an instructor demonstration, flown dual. It belongs to the same family as the cross-controlled stall, the elevator trim stall and spin training: maneuvers that are mishandled deliberately in order to teach something, and that are flown with a qualified flight instructor aboard, in an airplane approved and loaded for them — utility category, and inside the spin-approved weight and balance envelope where the POH requires it. Nothing below is a procedure to take up alone and try.

What a secondary stall is

A secondary stall happens when you exceed the critical angle of attack again during or just after recovering from the first one. Nothing about it is exotic. The Airplane Flying Handbook puts the cause in a single idea: you tried to return to the flightpath you wanted before the airplane was ready to fly there.

Most often that means excessive or abrupt back pressure during the recovery — you break the stall, then haul the nose back up before the airspeed supports it. It also comes from treating power as the recovery: adding throttle without ever reducing the angle of attack, so the wing is still stalled while the engine tries to compensate. Retracting flaps or gear too early will produce it, and so will any abrupt input while the wing is still near the critical angle. Power is not a stall recovery. Reducing angle of attack is the recovery, and nothing substitutes for it.

Keep the definition in front of you the whole time. The wing stalls when the angle between the chord line and the relative wind exceeds the critical angle, and that can happen at any airspeed, in any attitude, at any power setting.

Recognizing it

The recognition problem is that the recovery looks like it worked. The buffet stopped, the stall warning went quiet, the nose came up. Then the buffet returns, the stall warning reactivates, the controls go mushy again and the nose starts to drop a second time. It arrives before you have established a positive rate of climb or a controlled descent, which is exactly when a pilot is least willing to lower the nose.

Know what the warning in your airplane actually is before you go up, and brief your student on it — a horn in some airplanes, a light in others, a tone or a stick shaker in others still. Treat any return of the buffet or the stall warning during a recovery as a stall, not as turbulence. You are lower than you were at the first break and often less coordinated, so you have less margin than you had a few seconds ago.

Flying the demonstration

Clear the area properly, both directions, and know where you are relative to the rest of the training area. This curriculum sets an entry floor of 3,000 feet AGL. The 1,500 feet AGL you will see quoted is the single-engine airplane task standard for completing a stall recovery, not a universal number — multiengine demonstrations set their floors higher — and a maneuver that deliberately walks the wing back toward the critical angle deserves more room than the minimum. Start clean or in the landing configuration depending on which scenario you are teaching, and use the entry speeds and power settings in your POH.

Enter a stall normally for that configuration. At the break, begin what looks like a correct recovery, then deliberately return the elevator too soon and too far — before the airspeed will support level flight. The airplane comes back up against the critical angle, and at the first indication of that second stall you recover: the buffet, the stall warning, the first loss of control effectiveness, whichever reaches you first. The flight instructor standard is prompt recognition and recovery at the first indication, not a second fully developed stall, so letting it break again is a failure of the demonstration rather than a more convincing version of it. Check the exact task wording in the current Flight Instructor ACS before you brief it. The teaching point is the input and the cue, and your student has both the moment the warning comes back.

Recover in this order:

1. Disconnect the autopilot or wing leveler if one is engaged.
2. Release the back pressure and lower the nose until the stall warning stops, and hold it there until the warning stays off.
3. Once the angle of attack is reduced, roll the wings level with coordinated aileron and rudder.
4. Add power smoothly as needed.
5. Retract flaps and gear on the schedule your POH gives for a stall or go-around recovery — in stages, once the wing is flying and a climb is established, never as the first thing you reach for.
6. Return to level flight or a normal climb, stabilizing pitch and airspeed on the way rather than pulling to get there.

Brief the spin recovery before every flight that includes this demonstration, because the mishandling it asks for is the kind that drops a wing. If a spin develops, fly the procedure in the POH for that airplane. Where the POH gives none, the general recovery in the Airplane Flying Handbook is power to idle, ailerons neutral, full rudder opposite the rotation, elevator briskly forward through neutral until the rotation stops, then rudder neutral and a smooth pull out of the dive. If you would not be comfortable doing that in the airplane you are sitting in, that is a reason not to fly the demonstration in it.

What goes wrong

The first failure is not recognizing the second stall at all, and the second is answering it with more back pressure. Both come from the same instinct — the ground is close, so pull — and both are what the demonstration is meant to disarm.

Order matters more than most students expect. Leveling the wings before reducing the angle of attack, or reaching for power before reducing it, leaves the wing stalled while you work on something else. And if the recovery involves rolling out of a bank, remember that pulling in a turn raises the load factor: in a level, coordinated 45-degree banked turn the wings carry about 1.4 G and the stall speed is roughly 20 percent higher than wings-level. A recovery is not level flight, so take those figures as an illustration of how fast load factor climbs with bank rather than a number to fly by — the point is that a pull which would have been harmless wings-level can put you straight back through the critical angle.

Feet matter too. Uncoordinated flight at the stall can drop a wing, and a wing that drops while the airplane is stalled can develop into a spin. Keep the airplane coordinated through the entry, the break and both recoveries.

Overcorrection is the mirror-image error. Shoving forward hard enough to unload the airplane to zero or negative G, or diving to build far more speed than the recovery needs, are both faults on the same list. Lower the nose deliberately, not violently.

Managing the risk

Altitude is the first defense, and clearing turns are the second — you are about to spend a while looking at the nose instead of out the window. Turbulence and a high density altitude both cut into the performance you are counting on for the recovery, so brief them before you go up. Respect the airframe: the maneuver calls for a deliberately sloppy recovery, not an abrupt or excessive one. And watch for task saturation, in yourself as much as in your student — a demonstration where you are talking, flying and evaluating at once is where the improper input stops being intentional.

Where you meet it next

On the flight instructor practical test the secondary stall sits alongside the accelerated stall, the cross-controlled stall and the elevator trim stall — the group of demonstrations that exists because real stalls do not happen in the configurations we practice in, and every one of them is flown dual for the same reason.

You will meet the same mistake in the go-around, where full power against landing trim pitches the nose up on its own and the fix is identical: lower the nose, then trim, then climb. You will meet it on any base-to-final that gets tight, and on any attempt to stretch a glide toward the field in an emergency approach. And you will meet it in the ordinary power-off and power-on stalls your students fly every week, where inadvertent secondary stall during recovery sits in the common-errors list for a reason. The lessons on power-off stalls, power-on stalls, the cross-controlled stall, the elevator trim stall, spins, the go-around and the emergency approach and landing are all in the ground school.