When approaching a stall, is the first priority to apply power or lower nose?

Question

I’ve always wondered. And I’d assume it’s the same regardless of aircraft? But when approaching a stall would the main priority be adding more power?

I ask because what if a crew was on final for landing and approached a stall, the rear end is dropping and the nose is rising. I feel like the flaps at their current position during landing, would only make matters worse? And applying power could make more lift with a poor angle of attack?

Would a crew lower the flaps in that situation, after applying more power and pushing the control columns forward?

Answer 1

The instinct drilled into a pilot's head from the beginning as the primary response is "lower the nose" to lower AOA. If you learn in a glider, that's the only option, so it's easy to drill the instinct into peoples' heads (one reason that glider training before power is so good for pilot skills later). In a power plane, it's lower the nose and add as much power as you need, but lower the nose must be the first instinctive action. How much to lower the nose depends...

In a non FBW jet (FBW is another story, the computers taking care of things on your behalf whether you want them to or not), the stall training you get for low altitude stalls (you don't get to an actual stall - you start from stick shaker onset) is lower the nose but not too much, add thrust to maximum, and regulate the pitch attitude to stay just above stick shaker onset (just above the speed tape's "barber pole", the red broken band that indicates the stall region) and if flaps are at landing setting, call for retraction to go-around flap once you have stopped descending and are accelerating with decent speed margin above shaker.

The objective is to minimize the altitude loss as you recover airspeed. At shaker onset you still have some margin above the actual stall and if you're close to the ground you don't want to dive, so you just tease the pitch to hold it on the edge of shaker. You will generally use this procedure for any stick shaker event in denser air, below, say, 10000 or 15000 ft. As a general rule, you do not make configuration changes with gear and flaps until you have got yourself in a good situation energy wise (not sinking, accelerating - although there may be variations from a/c type to type) because retracting flaps can increase your sink rate and the standard procedure with gear is not to retract until there is a positive climb rate.

At high altitudes, especially above 30000 ft, the stick shaker recovery method is much more aggressive and you are trained to actually push over enough to lose several thousand feet and not be concerned with altitude loss. In the thin air the practice of teasing the pitch to stay just above shaker doesn't work so well, because the air is thin but the inertial mass of the machine is unchanged and that can get you into trouble if you fly it the way you do down low. You can find yourself back into the shaker/pusher/stall break region if you work the pitch to manage AOA on the edge of shaker the way you would close to the ground.

One of the events that lead to special high altitude stall recovery training during recurrent training was this famous (within the business) Pinnacle Airlines incident with a CRJ200 (quite a harrowing read; I don't think it was mentioned in the report, but the post crash fire was caused when they slid into a back yard garage with a meth lab in it).

Answer 2

The other answers have already correctly stated that lowering the nose is the first action, and that you do not fiddle with the configuration when stalled.

I'd like to add a point relating to smaller propeller aircraft: when flying at the edge of stall, or even stalled (some GA planes are surprisingly docile even under full stall), you do not want to suddenly push full power. Why not?

Your control authority is not at it's best. Controls feel "mushy", and the aircraft response is sluggish. If you suddenly bring into the game significant torque from the propeller, P-factor, slipstream starts pushing tail to the side... instead of getting out of the stall, you may very well have departed controlled flight, and are now spiraling towards ground with a hig power setting.

So: first secure control of the aircraft, then minimize altitude loss with power.

Answer 3

The priority is to unload the wings: which means lower the G load on the wings because the stall speed increases with higher G loads and reduces with lower G loads until reaching 0 with 0 G. So an aircraft can stall at any speed really, it all depends on the G factor it is subjected to.

That's why when you stall the first thing you should do is to lower the nose which means lower the AOA which means unload the wings which means reduce the actual stall speed which means get it as far as possible from your actual speed. The added power is used to reduce the loss of altitude during recovery which can be life saving if you are close to the ground.

Adding power on a below wing engine aircraft like the B737 can be dangerous because of the pitching moment the sudden add of thrust can generate which can make you stall again.

Answer 4

The priority is to reduce the AoA. This can be done in several ways (changing the attitude by lowering the nose, changing the chord line by lowering the flaps, thus reducing the effective AoA, increasing the airspeed by opening the throttle, thus lowering the effective Aoa...)

The choice depends on the flight conditions, and it's the pilot's choice...