Stall Recovery

[minitour]

BTW. Ask him if an aircraft can be flown to zero airspeed without stalling or if an aircraft can be stalled pointed straight down at the ground. That will give him something to think about.

and the answer to both is yes...absolutely.

I make it a point to show every student that the airplane WILL fly well below the bottom of the green/white arcs...


The way I teach stall recoveries (pwr off since that's relevant here) is to lower hte nose to the horizon which breaks the stall (remember, you only have to get lower than the critical AOA which in most cases doing approach to landing stalls, doesn't take much) and apply full power smoothly but quickly.

Get the positive rate of climb because of excess thrust, then clean up the aircraft appropriately. Flaps Gear Flaps Flaps.

IMHO

-mini

 

[viper548]

Get your instructor and the chief instructor together and ask how a stall recovery is done

 

[VNugget]

Change instructors.

 

[Magic1872]

and the answer to both is yes...absolutely.

I make it a point to show every student that the airplane WILL fly well below the bottom of the green/white arcs...


The way I teach stall recoveries (pwr off since that's relevant here) is to lower hte nose to the horizon which breaks the stall (remember, you only have to get lower than the critical AOA which in most cases doing approach to landing stalls, doesn't take much) and apply full power smoothly but quickly.

Get the positive rate of climb because of excess thrust, then clean up the aircraft appropriately. Flaps Gear Flaps Flaps.

IMHO

-mini

Exactly the same way I teach it as well. You only need to get the airfoil 1 degree lower than the critical AOA and the wing will start flying again.

 

[mddg3581]

Its more of a simultaneous flow. After breaking the stall establishing a nose to the horizon attitude will be sufficient to get a positive rate of climb and build airspeed. I retact first notch of flaps almost immediately and wait on the last two till there is positive rate of climb and increasing airspeed. I like to have my students pick some sort of floor though-theoretic runway. With this you can actually get an idea if you had a decent recovery or smashed into the runway.

 

[NYCPilot]

You don't need to necessarily point the nose towards the ground. When breaking a stall you want to decrease the excessive angle of attack. You do this by releasing the back pressure. There isnt usually a need to lower the nose towards the ground. This is really a coordinated maneuver which requires at the stall to release the back pressure (actually some planes require a more brisk forawrd movement). add power and bring that nose up to the horizon. One hand should be on the yoke and the other adding max power. After you've added power immediately take out one notch of flaps while your other hand is bringing the nose up to the horizon.

What may have happened is that you got in to a deep stall where the break caused the nose to drop a lot and you added power without getting the nose up in time.

 

[nosehair]

It is possible you were adding power as the nose broke and was pointing well below the horizon and then after thinking about it for a second or so, began to lift the nose above the horizon to climb away. I remember having students who'd do that in the early stages of stall recovery training and got better as time went on. Adding power while the nose was well below the horizon can cause rapid acceleration.

This is the scenario that could be the cause of such a statement. Diving the nose down to gain excesive speed to recover. I see students (not mine) who do that. Sure, that would be O.K. if you are stalling at several thousand feet, but we should practice recovering with minimum altitude loss - so the nose should only go slightly below the horizon, while ading power. The precise position of the nose should be an attitude and feel in the elevator that tells the pilot the airplane is unstalled. It's feel, as well as numbers, but it is always to a minimum nose low attitude.

The old instructor is right about applying power when the nose is pointed down - you will just go down faster. He may be just trying to point that out to you.

I point that out to pilots who use the "pitch to airspeed-power to altitude" technique on final. If you are low and your nose is pointed down, and you only add power, you will just go down faster. The technique is to coordinate simultaneous pitch and power, but a key point is to have the nose pointed in the correct direction when you add the power.

 

[mpflies2]

Well we’re obviously talking about power off or (approach to landing stalls). So in that case the recovery is relatively simple.

1. Smoothly reduce pitch attitude, pitch slightly below the horizon.
2. Power - Add full power then just continue the recovery with flaps etc.
The power and pitch changes above are by the book. Although in real-life flying situations, you're going to do them almost simultaneously.

In my training I too was taught lower the nose a bit below the horizon. However, after starting my CFI training at FSA, I have now been told to Go full power while simultaneously decreasing the AOA. So naturally, i thought this is what I had always done. I quickly found out that here they like you to lower the nose, but not below the horizon necessarily. The warriors Critical AOA is about 16 or 17 degress....since this stall (power off) is prolly happening during a landing flare to stretch a glide, you have very little altitude to recover. So anyways they have us lower the nose to about 5 or 6 degrees above the horizon. This does break the stall, and with simultaneous addition of power, I've found that its possible to lose virtually no altitude. Before I would lose about 150 feet.

Marc

 

[Say Again Over]

delete

 

[Say Again Over]

Delete.

 

[sbav8r]

I think you should talk to this instructor again. I'm going to assume that he is a competent CFI and what he was meaning to explain and what you heard are not the same. I have had students in the past try to add full power while allowing the nose to remain below the horizon. In this case, what he might have been trying to say is that you need to regain a positive rate of climb as quickly as possible; otherwise, your just increasing your kinetic energy (speed) into the ground. It sounds like there may have been some confusion in the communication process. Before you go getting a new instructor, sit down and discuss this again and make sure you are very clear on the procedure he wants you to learn.

What I taught is really no different than what everyone else is saying. Reduce the AOA and add full power and establish a climb. What you don't want to do is allow the nose to drop excessively and add full power at the same time. Doing this will only result in excessive loss of altitude and gain in kinetic energy. The point of the recovery is to establish a positive climb quickly and smoothly.

Typically, I shy away from using terms that associate stalls with the horizon, because the horizon really has nothing to do with it. The aircraft stalled because it exceeded the critical AOA; therefore, reduce the AOA. Start thinking of it this way now and it will help you later on when you start discussing more advanced aerodynamics. Like one of the other posters said, an aircraft will stall at any relation to the horizon including going straight down, it's all about relative wind and angle of attack.

Nosehair,
I just realized that I just said exactly what you had allready stated.

 

[A Squared]

I point that out to pilots who use the "pitch to airspeed-power to altitude" technique on final. If you are low and your nose is pointed down, and you only add power, you will just go down faster.

Only if the thrustline of your aircraft is pointed below your desired glidepath to the landing spot, Not impossible in a primary training scenario, but unlikely elsewhere. Add one more to the list of falacious arguements in the pitch-power debate.

 

[nosehair]

Only if the thrustline of your aircraft is pointed below your desired glidepath to the landing spot, Not impossible in a primary training scenario, but unlikely elsewhere. Add one more to the list of falacious arguements in the pitch-power debate.

Well, the primary training scenario is where I live and is exactly what I'm talking about. S'matter of fact, in my mind, ALL of these "debates" over pitch-power, rudder-aileron, and so forth are for the new guy. Once you have some time and experience, you understand that these applications must flow together, and seperating them into single one-two explanations, or initial response habit patterns are exactly for the beginning learner.

Every student I have flown with who has been trained to "pitch to the airspeed" on final approach, will pitch the nose up when encountering an up-draft. Later, in his instrument traning, if he is not corrected, he will pitch up on the ILS glideslope trying to control airspeed - it's an ingrained habit.

That's how I was taught - "pitch to the airspeed".

But, as I gained a litle experience, I realized I was being told to do that only on final approach. We don't do that in straight-and-level, or turns. We only do that in full power climbs and power off descents. In my day, all normal approaches were "power-off". So, of course, I had to pitch to the airspeed.

But that habit didn't change when I started learning "power approaches", and by the time I got the pitch and power coordinated, it didn't matter anymore.

Since I have been instructing so long, I have found that my primary students become much better at short/soft field approaches and instrument approaches when they initially learn to "point the nose" (maintain constant angle glidepath) with the elevator, and control the airspeed with the throttle.

Do you make power changes to keep the glideslope needle centered on an ILS? Well, do ya?

 

[Dr Pokenhiemer]

NYCPilot said, "You do this by releasing the back pressure. There isnt usually a need to lower the nose towards the ground."

He/She hit the nail on the head with that one. All you are doing is breaking the critical angle of attack. As you do this, by adding full power and holding the nose just above the horizon, you will stop sinking and will start climbing as you airspeed increases. On your checkride, I think the PTS says to recover from a stall without losing more than 50 feet (or something like that). If you push the nose forward, you will lose more than 50ft.

If an instructor is going to charge you and not teach you to standards-I'd change instructors. We tend to remember how to do things the way we were first taught. If we don't learn correctly the first time, it's harder to change to the right way.

 

[TOGA Happy]

Stalls, Spins, and Safety

What you really need is an understanding of a stall and not just a basic ability to recover mechanically. There is a book that is no longer in print called "Stalls, Spins, and Safety" by Sammy Mason. You can find it on EBay and Amazon. It is a great read and put in terms so that a simpleton like myself can understand it. I really do recommend that you read this book.

Just to put my 2 cents in (my daily pay) you should realize that a stall recovery is a reduction in the angle of attack (AOA). A stall is simply reaching the critical AOA of the wing and it is always at the same angle. It can, however, vary with speed. So, in a two dimensional (non-aerobatic flight) world, All you need to do is either reduce the AOA by bringing the yoke forward. Other post are correct in that adding power changes the flow over the wing. Also, with the power increase there is usually an accompanied increase in speed and a resulting change in the relative wind. This change in relative wind typically reduces the AOA and thus you have a stall recovery. That is why so many pilots incorrectly equate speed with safety when it comes to stalls. In training when the stall it is at a slow speed and during recovery they go faster. This is incorrect thinking....stalls can happen at any speed.

In aerobatic training, I was taught to break the stall by reducing the AOA first and then adding power. The reason being that if I add power and the aircraft is close to a stall, the result is that the aircraft can be aggravated into entering a spin and the power input also upset the spins. This is more typical on a more critical wing and less so on a Cessna Trainer wing. Once in a spin, the power is the first thing that should be reduced, the ailerons should be neutralized, opposite rudder to rotation should be used, and finally the AOA should be reduced.

Most all unintentional stalls that I have encountered have been at higher altitudes and at higher speeds with little to no buffet warning. Being at high speed meant I already had a high power setting, so all I had to do was reduce my AOA and I was good to go.

My guess is your instructor was simply wanting you to equate stall recovery with a reduction in AOA and not with an increase in speed by adding power (and changing the relative wind).

Thanks for listening to all that Jazz. Good luck and fly safe.