steep turns in the pattern

[woodstock]

Hi everyone

still really bummed about the accident at my airport a few days ago. I will be out there tomorrrow and Sunday - a XC and a regular more local flight.

I don't really know what happened yet but have been running possibilities over in my mind. it sounds as if it was on takeoff, and perhaps while they were turning.

if you do a regular straight ahead stall (i.e on departure), you would more or less go straight down - not nose first in the drop, right? just drop the whole plane... right?

and if you are on crosswind - just how steep of a bank is going to put you down like that? if you are really steep, but coordinated, you will lose altitude but not necessarily spin it in? being uncoordinated will just make it that much worse? (and harder to recover if at all).

I know to spin you have to stall the wings, you're going kinda slow on takeoff (let's say 75-80 or so, at Vy, slower if your nose is up more) but I know the speed goes down as you bank and steepen.

so worst case here is turning really steeply to the left... you're still hitting the right rudder because you don't know better or figure you are still climbing, etc... and your nose is higher than it should be. right?

I've talked to a friend of mine about this a few times and he said Pipers are really tough to spin but also a lot harder to get out once they are in a spin. I always thought the Cessnas were the most stable/easiest for flying but then others tell me the Pipers are much better. (not trying to get this into a high wing low wing debate!)

I'm not looking forward to tomorrow. I'm sure it's going to be really somber at the airport.

 

[gismo]

if you do a regular straight ahead stall (i.e on departure), you would more or less go straight down - not nose first in the drop, right? just drop the whole plane... right?

No, if you remember from stall practice, the airplane pitches down significantly when you stall the wings. It doesn't come anywhere near straight down either because when you stall, your airspeed doesn't drop to zero.

and if you are on crosswind - just how steep of a bank is going to put you down like that? if you are really steep, but coordinated, you will lose altitude but not necessarily spin it in? being uncoordinated will just make it that much worse? (and harder to recover if at all).

I know to spin you have to stall the wings, you're going kinda slow on takeoff (let's say 75-80 or so, at Vy, slower if your nose is up more) but I know the speed goes down as you bank and steepen.

so worst case here is turning really steeply to the left... you're still hitting the right rudder because you don't know better or figure you are still climbing, etc... and your nose is higher than it should be. right?

I've talked to a friend of mine about this a few times and he said Pipers are really tough to spin but also a lot harder to get out once they are in a spin. I always thought the Cessnas were the most stable/easiest for flying but then others tell me the Pipers are much better. (not trying to get this into a high wing low wing debate!)

I'm not looking forward to tomorrow. I'm sure it's going to be really somber at the airport.

Stall speed goes up in a turn reaching roughly 1.5 time the "normal" stall speed at 60 degrees assuming you are coordinated. If the coordination isn't maintained and the plane stalls then it's likely that a spin will begin.

 

[woodstock]

thanks Lance. I'm going to stop speculating b/c the reports are so conflicting. but for sure I'm going to re-read about stalls and spins again. maybe we'll have time to practiec them tomorrow.

 

[RotaryWingBob]

What Lance said. Stalls, IMHO need to be understood, but not a cause of panic -- lower the AOA and the stall goes away. Keep the wings level, and no spin...

 

[Dave Krall CFII]

thanks Lance. I'm going to stop speculating b/c the reports are so conflicting. but for sure I'm going to re-read about stalls and spins again. maybe we'll have time to practiec them tomorrow.

The things you're planning to train again on are extremely important regardless of what was involved in the crash earlier this week.

Keep your aircraft nose down enough to conserve kinetic energy in the turns so that the wings don't even get near stalling in the pattern in these generally underpowered GA trainers.

Try going out at higher altitude but with horizon and ground still readily visible and with CFI & simulate pattern OPs & potential mistakes and corrections. Also just do some steepening turns until it stalls while keeping an eye on the nose attitude, engine sounds, etc.

It's fun and will make you safe.

 

[Richard]

No, if you remember from stall practice, the airplane pitches down significantly when you stall the wings. It doesn't come anywhere near straight down either because when you stall, your airspeed doesn't drop to zero.



Stall speed goes up in a turn reaching roughly 1.5 time the "normal" stall speed at 60 degrees assuming you are coordinated. If the coordination isn't maintained and the plane stalls then it's likely that a spin will begin.

I thought 60* is when stall speed doubles (2x).

 

[Don Jones]

I thought 60* is when stall speed doubles (2x).

Nope, Its the load factor that doubles Richard. 60 degree bank= 2 G's
Don

 

[wsuffa]

Beth,

The best thing you can do is to study accident reports and make a vow to learn from them.

Really.

 

[Richard]

Nope, Its the load factor that doubles Richard. 60 degree bank= 2 G's
Don

Uhhh, I knew that. Chalk it up to brain drift.

 

[Skip Miller]

Keep the wings level, and no spin...

I think you meant to say: Keep the ball centered, and no spin. A stall while level and uncoordinated can start a spin.

-Skip

 

[RotaryWingBob]

I think you meant to say: Keep the ball centered, and no spin. A stall while level and uncoordinated can start a spin.

-Skip

That is more correct than the way I put it

 

[DoubleD]

Remember, you can't stall if you don't reach the critical angle of attack. And you can't reach critical AOA if the yoke isn't completely back (in most planes). The yoke(stick) is in effect an AOA indicator. Learn to become more conscious of its position and you'll inoculate yourself against an inadvertent stall.

 

[fgcason]

And you can't reach critical AOA if the yoke isn't completely back (in most planes).

Since when?

I've been doing stalls in planes for years without having the stick all the way back. And on a departure stall, it's very easy to setup a stall condition where the stick is nowhere near the aft stop. Hitting the aft stop just makes the stall more fun.

Learn to become more conscious of its position and you'll inoculate yourself against an inadvertent stall.

That's just bad advice IMO. I can see where the idea comes from under certain specific conditions, but the two are not directly related. IMHO control position is less effective than watching the airspeed indicator to determine AOA..and the airspeed indicator can only give you an idea of where the stall (critical AOA) is going to occur.


IMHO: Maintain flying speed, not the needles or control positions. If the stick is getting mushy on you regardless of it's position, you're asking for a stall and really should do something to correct it right then.

 

[DoubleD]

As we've all learned, airplanes can be stalled at any airspeed and in any attitude, but only when the critical angle of attack is exceeded. I've never personally flown an airplane that would allow exceeding critical AOA at anything other than full aft stick position. There is no need that I can think of to design in the capability to exceed critical AOA by a large margin.

At less than full aft stick, the nose may drop, you may lose altitude, but you won't stall.

I am open information from others with different experience.

 

[gismo]

As we've all learned, airplanes can be stalled at any airspeed and in any attitude, but only when the critical angle of attack is exceeded. I've never personally flown an airplane that would allow exceeding critical AOA at anything other than full aft stick position. There is no need that I can think of to design in the capability to exceed critical AOA by a large margin.

At less than full aft stick, the nose may drop, you may lose altitude, but you won't stall.

I am open information from others with different experience.

IME, this is hugely dependent on make/model, power level, g force, and CG location (and in some cases the position of the trim).

What you say may well be true for some planes at idle power with wings level and nobody in the back seat, but I wouldn't count on it under the full range of conditions in any airplane, and in any condition in some planes.

The elevator can be considererd an AOA control, but the effectiveness of that control surface is dependent on the airflow over it. At high power / low speed there is a significant portion of that airflow that's produced by the prop. And when you are in a steep coordinated turn, the stall speed is higher giving the elevator more authority than it has in level flight.

I think you should be able to visualize that the relationship between elevator position and AOA would vary with CG as the lever arm changes.

And I could swear that the position of the stick is less aft when stalling in very high DA, but I can't for the life of me think of a valid reason for this so I could just be remembering incorrectly.

 

[poadeleted20]

I've never personally flown an airplane that would allow exceeding critical AOA at anything other than full aft stick position.

I'm sure that's a result of not having been exposed to the full range of high AOA flight of which even the light simple trainers you've flown are capable. While it is true that in a typical stall training exercise with a slow deceleration and pitch rate of one or two degrees per second, it is almost impossible to fully stall a light training plane without full aft yoke, you can get even a C-150 to stall with much less than full aft yoke, especially if you get the nose well down, as in a spin recovery.

The issue here is high speed and g-loading, and with that, you may be really surprised by how little stick movement is needed to exceed critical AOA. The secondary stall in this situation is one of the "gotchas" that folks undergoing spin recover training have to learn so they get past the misconception that folks inadvertently pick up as a result of negative training transfer from routine stall training. My first exposure to this was when I fell out of a barrel roll in a T-34 more than 30 years ago, got pointed straight nose down, and pulled too hard as the speed started to build. The need to control the pull to avoid getting too deep in the buffet made a very distinct impression on me, reinforced by trainee errors when giving spin recovery training in C-150's later on.

 

[Henning]

Keep the wings level, and no spin...

not necessarily

As we've all learned, airplanes can be stalled at any airspeed and in any attitude, but only when the critical angle of attack is exceeded. I've never personally flown an airplane that would allow exceeding critical AOA at anything other than full aft stick position. There is no need that I can think of to design in the capability to exceed critical AOA by a large margin.

At less than full aft stick, the nose may drop, you may lose altitude, but you won't stall.

I am open information from others with different experience.

Bunch of planes you haven't flown then, and a bunch of loading conditions you haven't had as well. If you are flying slow and heavy in nearly any plane you can pull a stall without coming near the yoke travel limit. I had a cargo of shrimp and ice shift in a 185 once where if I didn't hold full forward I would have stalled, tail first at that. Had to have my pax start scooping it forward. Never worry about where a control is, concentrate on how the control feels as well as the way the aircraft responds to it.

 

[DoubleD]

I stand corrected, and thanks for your helpful comments.

 

[SkyHog]

As we've all learned, airplanes can be stalled at any airspeed and in any attitude, but only when the critical angle of attack is exceeded. I've never personally flown an airplane that would allow exceeding critical AOA at anything other than full aft stick position. There is no need that I can think of to design in the capability to exceed critical AOA by a large margin.

At less than full aft stick, the nose may drop, you may lose altitude, but you won't stall.

I am open information from others with different experience.

So then you've never flown a Cessna Skyhawk? I can actually say that I have stalled them from slow flight during training, where the yoke wasn't even close to full aft. In fact, I'd wager that the majority of my power on and off stalls were done without the yoke full aft.

My Cherokee is similar (although it seems to not want to stall unless it is full aft, it can be stalled without it).

edit: ^^^ oops - I missed that you had rescinded the statement. Accept my apologies?