The flight test requires that Private Pilot Students perform two stalls, and Commercial Pilot Students perform one stall. For Private Pilot Students, the first stall is a power-off entry, and the second stall is a power-on entry . For Commercial Pilot Students, the stall shall be entered from a practical flight situation.
Students must demonstrate that they can recognize indications of the approach to arrival (power-off) stalls, the full stall, and demonstrate the skill to accomplish a positive and smooth recovery with a minimum loss of altitude .
You must demonstrate this stall at an operationally safe altitude that allows recovery at or above the attitude recommended by the manufacturer or 2000’ AGL, whichever is higher. The stall will be entered from a power-off situation, with the configuration of the aircraft specified by the Examiner.
Private Pilot Students must:
Private Pilot Students must demonstrate that they can recognize indications of the approach to a departure or overshoot (power-on) stalls, the full stall, and demonstrate the skill to accomplish a positive and smooth recovery with a minimum loss of altitude.
You must demonstrate this stall at an operationally safe altitude that allows recovery at or above the altitude recommended by the manufacturer or 2000’ AGL, whichever is higher. The stall will be entered from a power-on situation, with the configuration of the aircraft specified by the Examiner
Private Pilot Students must:
Commercial Pilot Students must demonstrate that they can recognize indication of the approach to either departure or arrival stalls, the full stall, and demonstrate the ability to accomplish a positive and smooth recovery with a minimum loss of altitude.
You must demonstrate this stall at an operationally safe altitude that allows recovery at or above the altitude recommended by the manufacturer or 2000’ AGL, whichever is higher. The stall will be entered from practical flight situations, such as slow flight, simulated overshoot, or a climbing or descending turn. The configuration of the aircraft specified by the Examiner.
Commercial Pilot Students must:
Your Instructor will introduce you to a varied of stalls, based on the use of power during the entry and recover. Roughly, they are classified as indicated below, left. The power-off stall with a power-off recovery will be flown, as without the use of the engine, the “buffet” associated with a stall is more clearly discernable. The power-off stall with power-on recovery is the most practice most commonly, with the use of power being effective means at hasten the recovery and minimize the altitude loss. Of the three, the power-on stall with power-on recovery is the most complex of the stall variations as the aircraft is more likely to drop a wing, and the symptoms of the stall are somewhat concealed from the pilot with the propeller thrust acting to hold the nose up—during the power-off entry, the dropping of the nose is quite discernable and obvious, but not so in the case of a power-on stall.
A HASEL check must be conducted before the manoeuvre. After completing the lookout, line up the aircraft with a prominent landmark (preferably “the grid”—the east-west avenues or north-south streets). Remember not to delay between the lookout and the entry into the stall.
With respect to power-off entry stalls, begin the manoeuvre by slowly reducing the power—as the power is reduced, you will have to concentrate on smoothly controlling both pitch (the nose will want to go down) and yaw (the aircraft will want to yaw to the right—opposite to when you apply takeoff power). The ideal performance is to smoothly adjust pitch to maintain level altitude (reference for pitch should be the altimeter), and smoothly apply rudder to keep the aircraft going straight—the smoother you are with the power reduction, the easier it will be to control yaw and pitch. As you approach the stall, the three primary symptoms will occur in succession—the stall warning system will trigger (light or horn), then the buffet caused by turbulent flow will felt and heard, and finally the nose will drop. Remember, with the first onset of the stall symptoms, you should concentrate on reducing the amount of aileron input you use, until, near the stall, the aileron will have to be absolutely neutral—plant your elbow on the elbow rest and this will hopefully remind you.1
If you do not hold the ailerons neutral, one wing will become more stalled then the other—a differential stall—which, of course, is how the autorotation associated with spins develops. So, you may ask, how do you keep the wings level when approaching a stall? The answer, not surprisingly, rests with your feet: use rudder to gently but aggressively keep the aircraft straight and the wings level. Approaching the stall you will feel and hear buffeting—caused by the turbulent flow of air on the wing which vibrates the wings, fuselage, and tail empennage. Remember that the buffeting only identifies an impending stall; the stall is achieved only after the buffeting when the nose “falls,” despite pitch-up command.
The importance of directional control during a stall warrants special consideration. As the power is reduced for the entry, the aircraft will yaw right; it is therefore important to offset this yaw with smooth left rudder. To do this effectively, you must have a prominent landmark as reference for keeping the aircraft straight. If you try to correct direction too late—after a stall has occurred—you will invite a wing drop, so get the right rudder in before the stall occurs. After the stall is occurring (from the buffet through to the nose drop), your attention is best focused on simply keeping the wings level—at this point, keeping straight is secondary.
With respect to a power-off stall using a power-on recovery, you should initiate the manoeuvre using sufficient back-pressure on the control column (after power is smoothly reduced to idle) to maintain altitude—this should be smooth throughout, but as the stall approaches you will usually have to increase the rate at which you pull back the column (remember the ailerons are neutral). When the nose drops despite the back-pressure, the stall is achieved; you should then smoothly decrease the angle of attack with forward stick pressure until the buffet stops,2 and full power should be smoothly but aggressively applied. As soon as you have lowered the nose, the stall is usually broken and it is fair game to begin using the ailerons again to keep the wings level. With the application of throttle, and the lowering of the nose, remember to use your feet aggressively to keep the nose straight (the application of power will of course cause a left-yaw tendency). Remember that the name of the game is “minimal altitude loss” so avoid pushing the nose forward (downward) any more than it is necessary to stop the stall buffet.
The power-off stall with a power-off recovery is the most basic form of a stall, designed to prepare pilots for a stall occurring during a departure climb when the engine has failed (and power now cannot be used as a recovery tool). The stall entry is the same as above, but the forward or downward pitch required for the recovery will be greater than in the case for the power-on recovery. Nevertheless, be sure that you do not pitch down excessively here—the rule still applies with respect to minimal pitch to exit from the critical angle of attack back to a safe angle of attack.
With a power-on stall, the idea is to expose yourself and the aircraft to the higher angles of attack usually associated with a power-on stall for as little time as possible (quite simply stated, the longer you hold the nose up with the power on, the more likely you are to develop the incipient spin feature of a wing drop). After completing the required checks, set the power as required, keeping the aircraft straight and level. After the speed slows to about Vsl + 15, progressively but smoothly raise the nose to an approximate angle of 30° above the horizon—then hold it there with appropriately increasing back-pressure, not allowing the nose to rise or fall until the stall is achieved. Then, when the nose falls despite backpressure, lower the nose sufficiently to break the stall with, of course, full power. Again, pitch forward only to the extent that is required to unstall the aircraft and exit from the critical angle of attack (that is, stop the stall buffet). The rudder work stays the same as with a power-off stall, but you will have to be more aggressive as there will be more left yaw tendencies to control as you raise the nose, and there will be a tendency for wings to fall faster. In keeping the wings level, however, smoothness in your inputs is the key, as this will reduce the need for jerky rudder work.
In addition, you Instructor will introduce you stalls during turns, with and without flaps. With turning stalls, and stalls using extended flaps, the inputs are surprisingly normal. The steeper the turn used for the stall entry, the more adverse will be the stall (make it easy on yourself and limit the angle of bank to 30° or less). With stalls in a flap configuration, the procedure for recovery is the same as with a no-flap stall, except that you retract the flaps after you have recovered and placed the aircraft in a climbing attitude. Remember most of all that, despite the type of stall you perform, the name of the game is a minimal loss of altitude.
Further Readings:
Transport Canada's Stall/Spin Training
1 The failure of examination candidates to maintain neutral aileron at or near stall speed is a classic error performed on a flight test—it is considered a “major” and Examiners are looking for it—and it is a habit you best establish early in your flying. The danger associated with aileron use at the stall is the risk of creating a “differential” stall where the wings are stalled differently—here you are just inviting one wing to stall, and with this a spin has begun.
2 An important message here is that you must remember that all of our training occurs in the utility category where the centre of gravity is forward. In a normal flight, however, with normal category loading (associated with a rearward centre of gravity), anticipate that far more aggressive and dramatic forward pressure on the control column will be required to exit the stalled condition—unfortunately, we cannot demonstrate this in flight training as it would be too dangerous, but at least we can make you aware of this hazard.
3 A member of the Snowbirds was killed while performing in Toronto when he suddenly lost control his Tutor aircraft; the accident investigation concluded that the pilot came out of his harness and ended up on the control stick. It is easy to conceive of a “g” force that would “peg” you against the control column making it impossible for you to recover. To politely check the security of your passenger’s seatbelt, tug on the belt just above where it is bolted to the floorboards.
4 A skilled pilot requires less than 100’ to recover from a stall; but the same pilot requires 700’ to recover from a 1-rotation spin—altitude that might not always be available.
5 Non-aerobatic aircraft are physically strong with respect to positive “g” forces, but their backs can be easily broken by negative “g” forces—the risk of a negative g-force occurs here in a rapid pitch-down movement (identified to the pilot when strained against the harness).
