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How to recover from a tip (wing) stall?

Old 01-24-2011, 08:31 PM
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Capflyboy05
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Default How to recover from a tip (wing) stall?

I'm not sure this is the right area to post this in...
I already can recover from regular stalls.
But what other stalls are there that I should know how to recover from?
Also is there such a thing as a stall you cant recover from? Regardless of your altitude?
I flew for a while, from 12-15, then stopped until now (I'm 18).
I can still fly my trainer by myself.
I'm just trying to get more technical and experienced rather than just flying..
I do know that most experience comes from flying.
I've crashed before...
To the point NOTHING but servos and radio equipment were recoverable...
Saddest day of my life.


Old 01-24-2011, 08:48 PM
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Montague
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Default RE: How to recover from a tip (wing) stall?

For most models, given enough altitude, you can get out of any stall. Of course some models take a lot longer to get out of some situations than others.

You can set up a model so that you can get it into a spin that you can't recover from or that will take more altitude than you'd reasonably have when flying models. I've seen it done a couple of times (with the messy results). (to do it, you need a small vertical tail, and a fairly high wing loading, and usually a lot of control throw to get into the spin in the first place).

There are also lots of planes that you an set up to do a really deep flat spin where the plane won't come out if you just release the controls, but will come out if you give the right controls in time.

In terms of "types of stalls", it's a matter of one wing or both being stalled and how much. You can also sometimes stall the horizontal tail as well, but that takes work.
Old 01-24-2011, 09:29 PM
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Default RE: How to recover from a tip (wing) stall?

altitude, and or power
Old 01-24-2011, 10:53 PM
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TimBle
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Default RE: How to recover from a tip (wing) stall?

tip stalls usually result in a pin of sorts.
to recover you need;

- Lots of rudder authority
- altitude
- speed
- CG ahead of the Centre of pressure of the wing or at least not less than 35%MAC.

Basically you need a well set up plane to make recoveries easy and matchstick less
Old 01-25-2011, 04:18 AM
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Default RE: How to recover from a tip (wing) stall?

Basically you need a well set up plane to make recoveries easy and matchstick less
Priceless!!
Old 01-25-2011, 04:54 AM
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Default RE: How to recover from a tip (wing) stall?

For example. I had a small scale Lockheed Vega. It didn't have enough vertical fin. On the second flight when trying to determine if it would stall nicely or nastily, it littereally snapped into a left hand spin. Full opposite aileron and rudder with full down elevator got it stopped and in a dive. But at the bottom of the dive in the pull out it went into an accelerated stall and spun the other way. Not enough room left to recover.[sm=crying.gif] The plane is rebuilt and hanging in the resturant at Wiley Post airport in OKC.
Old 01-25-2011, 05:00 AM
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bkdavy
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Default RE: How to recover from a tip (wing) stall?

The best way to recover from any stalled condition is to RELEASE all your control inputs, then add throttle. This will remove anything the control surfaces are doing to deepen the stall, and begin adding air speed. Once you have recovered your airspeed, resume normal controls.

Brad
Old 01-25-2011, 06:35 AM
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Default RE: How to recover from a tip (wing) stall?

tip stall will put you in a spin...adding just elevator will make the spin worse....stop the spin with opposite aileron or rudder.....this should now have you in a nose down atitude.....add power and pull out with elevator.....need to have the altitude or it just isn't going to happen
Old 01-25-2011, 07:06 AM
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Default RE: How to recover from a tip (wing) stall?

Never, and I mean NEVER try to stop a spin using aileron. In a normal spin, that is not inverted, recovery will be, throttle off, neutral aileron, full down elevator and full rudder opposite the spin. When the spin stops release rudder, roll level, and slowly pull out of the dive while adding power. Flat spins are the same except you need power while recovering. You will find if your plane is not setup properly, such as balance, then the technique could vary. At that point you are a test pilot, and try anything. The thing to remember about stalls and spins is they happen at a given AOA not airspeed. Spins happen because one wing is farther past that critical AOA then the other. The main reason is aileron deflection, this changes the AOA of the wing. A roll to the right during a stall makes the left wing have a higher AOA and therefore is more stalled resulting in a spin to the left. Adding more aileron only makes it worse. Rudder is your friend at high AOA's. Rudder has a much lower effect on AOA for the amount of control it provides. Most spins occur due to the pilot trying to correct for a yawing moment using the ailerons, when rudder should be used, or using excessive amounts of rudder. Bottom line, unless you are really good or have a really stable A/C, keep your speed up.
Old 01-25-2011, 07:29 AM
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Default RE: How to recover from a tip (wing) stall?

@Capflyboy05 -

I had many of the same questions you have but, many years after the fact that I had been flying rc. I couldn't figure out why some things were going wrong and knew I was missing somthing. So I went back to the basics and got my "learn on" courtesy of the Dept. of Transportation &FAA.

http://www.faa.gov/regulations_polic...lane_handbook/

This is one of the very first books you get when training to fly full scale and I have found it to improve my rc flying skills dramatically. Download Chapter 4: Slow Flight, Stalls, and Spins. I put it all into practice at the flying field regularly and have reaped the rewards ever since.

"When the airplane is in a stalled condition, the wingtips continue to provide some degree of lift, and the ailerons still have some control effect. During recovery from a stall, the return of lift begins at the tips and progresses toward the roots. Thus, the ailerons can be used to level the wings....It should be reemphasized that a stall can occur at any airspeed, in any attitude, or at any power setting, depending on the total number of factors..." Airplane Flying Handbook; U.S. Department of Transportation - Federal Aviation Administration

Old 01-25-2011, 07:38 AM
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Default RE: How to recover from a tip (wing) stall?

To address the OP's question.

There is only one stall recovery. That is to reduce the wing's angle of attack. This is usually done by relaxing the back-pressure on the control column; and this is the only action that is guaranteed to "break" the stall.


The clever contributors on here will also know that you can sometimes reduce the angle of attack by reducing the airflow over the elevators ... so a power reduction might fit the bill. A power increase will almost certainly exacerbate the symptoms of the stall; unless it is accompanied by an appropriate reduction in the wing's angle of attack.





But, for your purposes, the answer is "stick forward". "How far forward?" ... well, just enough to reduce the wing's angle of attack to somewhere below its critical angle.




Now, have I missed anything?
Old 01-25-2011, 09:22 AM
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Default RE: How to recover from a tip (wing) stall?

tip stall is that stall that occurs when the plane is in a bank and suddenly drops a wing tip resulting in a spin. This stall occurs because the weight of the aircraft has increased due to the radius of the turn being to tight. The wing can't hold the aircraft because its stall speed has been increased due to the higher weight. Recovery from the resulting spin...Everyone is of course correct about stall recovery for angle of attack related stalls.
Old 01-25-2011, 10:06 AM
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Default RE: How to recover from a tip (wing) stall?

ORIGINAL: Capflyboy05

I'm not sure this is the right area to post this in...
I already can recover from regular stalls.
But what other stalls are there that I should know how to recover from?
Any airplane attitude respect to the airflow that takes the AOA of the wing beyond the critical AOA, will detach the flow of air from the top of the wing, where most of the lift effect is generated.
As long as that excessive AOA is kept, the wing will start producing a lot of drag and much less lift in that stalled condition.

Different airfoils transition from flying to stalling with different abruptness.
Small geometric differences between both half-wings (airfoil, warp, area, etc.) may make one of them reach the stall condition sooner that the other.
Different wing plan-forms (square, elliptical, etc.) start developing the airflow detachment and loss of lift by the root (producing a mushy descend) or closer to the tip (producing a rapid roll if one tip stalls sooner).

Contrary to popular belief, slow speeds don’t induce sudden wing stalls.
There is a critical speed, called stall speed (from full size airplanes terms), below which the lift force that the wing generates is less than the weight of the airplane, making it descend (in a more or less controlled way).

Some examples of wing stall situations are: sudden nose up (3-D maneuvers and leveling after a fast dive), tight banked turns, aileron use (down) during slow landing (the most dangerous stall, I believe), snap rolls and spins.


Also is there such a thing as a stall you cant recover from? Regardless of your altitude?
Recovering from stalls are only possible if:
1) The AOA is reduced under the critical value (nose down (and neutral aileron if caused by down aileron)).
2) Airspeed over the wing is increased in order to induce reattachment of the airflow (dive and engine rev up).
3) Any rotation or spin is stopped, so 1 and 2 are possible for both half-wings at once (strong ruder (ailerons are not recommended here). Some airplanes have tail configurations that can, during a spin, blank the airflow for either the elevator or the rudder, making them less effective for recovery. With sufficient altitude, most of the tip stalls develop into a full spin.



I flew for a while, from 12-15, then stopped until now (I'm 18).
I can still fly my trainer by myself.
I'm just trying to get more technical and experienced rather than just flying.
Then reading these previous RCU threads will be good for your understanding of stalls and recoveries:

http://www.rcuniverse.com/forum/m_89..._1/key_/tm.htm

http://www.rcuniverse.com/forum/m_95...tm.htm#9530648

http://www.rcuniverse.com/forum/m_10...m.htm#10038186

http://www.rcuniverse.com/forum/m_10..._1/key_/tm.htm


I do know that most experience comes from flying.
I've crashed before...
To the point NOTHING but servos and radio equipment were recoverable...
Saddest day of my life.
It seems that your life has been short and pleasant
Old 01-25-2011, 12:18 PM
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Default RE: How to recover from a tip (wing) stall?

ORIGINAL: Capflyboy05

I'm not sure this is the right area to post this in...
I already can recover from regular stalls.
But what other stalls are there that I should know how to recover from?
Also is there such a thing as a stall you cant recover from? Regardless of your altitude?
//SNIP//
Capflyboy05, your title was about "tip stalls" and your text covers others. Most of all your questions are answered above so I will just talk about the dreaded "tip stall".

"Tip stall" is generally just a name given to that sudden wing drop that generally happens on maybe a take-off or landing. A stall, in subsonic convergent air flow is when the laminar flow ( uninterrupted flow in a fluid [air] near a solid boundary in which the direction of flow at every point remains constant) separates from the wing, stabilizer, or any object within the specific airflow.

In RC due to- 1. the pilot is not in the cockpit and recognizes such a tad late, and 2. many model airplanes, especially with ailerons to the wing tips - it is easy to use too much aileron in correcting a droping (or just drooping) wing when using considerable elevator to either lift off or hold the nose up for a landing. If a wing tends to drop, the RCer usually uses aileron to correct. At the lower than normal speed, or with surface wind gusts, the airflow at the down aileron will separate from the wing's normal laminar flow, creating a strong decrease in lift rather than the desired increase of added lift. The model rolls against the desired direction and BOOM a repair job is ordered. []
Rudder application is the best control when a model tends to roll or yaw during any time the current use of elevator calls for a higher than normal angle of attack. Get up some altitude and give it a try.

If you can train yourself to use the rudder for more roll corrections during the landing phase or take-offs, you will very probably not experience this "tip stall" demon during landing and take-offs.

I use to try to advise lesser experienced RC pilots to roll the ailerons on their new heavy warbirds up to about a 3/16 to 1/8 at the trailing edge prior to a first flight. Those that did usually never came down much on the adjustment. Most that did not just headed back to the work shop.
(EDITED to add: That correction of ailerons just insured that wing was properly "washed out". Check from behind any heavy aircraft sitting on the ground. The wasout is very seeable.)

Most of the younger crowd are not like you, Capflyboy05. they do not seek answers, as they already know everything.
So congratulations on your searching with an open mind. Very impressive.



Old 01-25-2011, 04:26 PM
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Default RE: How to recover from a tip (wing) stall?


ORIGINAL: TimBle

tip stall is that stall that occurs when the plane is in a bank and suddenly drops a wing tip resulting in a spin. This stall occurs because the weight of the aircraft has increased due to the radius of the turn being to tight. The wing can't hold the aircraft because its stall speed has been increased due to the higher weight. Recovery from the resulting spin...Everyone is of course correct about stall recovery for angle of attack related stalls.
Tip stall is a term used to describe an uncoordinated stall. That is, a stall in which one wing has a higher angle of attack then the other when it reaches stall. There are several ways this can happen, a steep turn, slow speed flight, a high "G" pull up, or any combination of these. In all cases the rudder is applied either too little or too much causing an uncoordinated condition and one wing to stall more. This can happen at any speed at or below, theoretically, manuevering speed (Vma) depending on "G" load or amount of uncoordination. A steep turn is the most common factor for both MA and FS.
Old 01-25-2011, 06:22 PM
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Default RE: How to recover from a tip (wing) stall?

I have had planes tip stall but recover?? So far I haven't figured it out. I'm usually going too slow on a landing and a few inches or feet off the ground. The only in air stall I have had was with a bipe and when it stalled I had a hundred feet or so, it went into a hard, fast snapping spin and as hard as I tried noting helped. Another friend with the same plane had the same thing happen, too slow, too low and turning into too sharp of an angle. What caused the stall I know, my bad. What I could have done about it?? Maybe being higher so I had some time to work on the problem.
Old 01-25-2011, 06:50 PM
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Default RE: How to recover from a tip (wing) stall?

Yes, the best advise is to not let it stall in the first place. most stalls are low to the ground and even an advanced flier may not have enough altitude to recover. Practicing stalls at altitude from different attitudes can help you learn what attitudes and inputes to avoid to keep from stalling.
Old 01-25-2011, 08:05 PM
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Default RE: How to recover from a tip (wing) stall?

And not all planes are prone to stalling. The Bipe I lost in my big one was this little Krier kraft, scratch built from Gordon Whitehead plans. It was powered with a YS 1.10. I was also showing off when it happened and trying to side slip it in for a landing in front of the guys. I have now lost three planes showing off and decided it wasn't the best thing to do. I'm also not good enough to be showing off anyway!! The other is my one off Patty Extra 300. I have flown a lot of Extras, one of the better planes around. They are not prone to stalling and if you are flying too slow they give you a wing bobble for a warning, this one doesn't. I gave it away a few months ago. It also wanted to stall if you weren't under power and pulling out of a horizontal. I once stalled it a couple feet off the ground, managed to touch all four tips but didn't hurt the plane. Another foot higher and it would have required repairs. That was my only Extra that gave no stall warning. You can look at the Krier and see why you had to watch it, I didn't!!
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Old 01-25-2011, 11:12 PM
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Default RE: How to recover from a tip (wing) stall?

Ok I am going to knit pick here....snip snip snip
ORIGINAL: cfircav8r


ORIGINAL: TimBle

tip stall is that stall that occurs when the plane is in a bank and suddenly drops a wing tip resulting in a spin. This stall occurs because the weight of the aircraft has increased due to the radius of the turn being to tight. The wing can't hold the aircraft because its stall speed has been increased due to the higher weight. Recovery from the resulting spin...Everyone is of course correct about stall recovery for angle of attack related stalls.
Tip stall is a term used to describe an uncoordinated stall. That is, a stall in which one wing has a higher angle of attack then the other when it reaches stall.Correct thus far There are several ways this can happen,This is where it gets iffya steep turncorrect, slow speed flight,Maybe but I'll come backto this latera high "G" pull up, Only where the plane did not enter the manuoevre from straight and level. In a high G pull up the wing stalls.Period. One wing dropping is a result of a wing weight problem on theairplane. Try it. Everytime you try a high G pull up the plane drops the samewing because that wing isHEAVIER. This is an aircraft set-up problem. The pilot has not balanced the aircraft laterally. This is NOTa TIPSTALL, its a wing weight problemor any combination of these. In all cases the rudder is applied either too little or too much causing an uncoordinated condition and one wing to stall more. This can happen at any speed at or below, theoretically, manuevering speed (Vma) depending on "G" load or amount of uncoordination. A steep turn is the most common factor for both MA and FS.
In slow speed, you are correct, to aggresive rudder application can result in too rapid yaw which could stop a wing halfinstantaneaously resulting in a "tip Stall". That is a factor of slow air speed at the wing tip. Generally slow speed does not simply result in a stall because increasing the wings AoA will reduce the tendency to stall. AoA and airspeed are the contributors.

More on the high G pull up, if the planes attitude is not level pulling into the pull up i.e. the plane was not flying staight and level to begin with and one wing was lower or travelling slower than the other the result will be that once the plane is vertical it will be skew. The wing tip that is lower will drop first but the whole wing has stalled already. In these cases omne side is not more stalled than the other, they are both stalled. The stratic forces acting through the CG make it appear to be a tip stall but its not.
Old 01-26-2011, 07:19 AM
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Default RE: How to recover from a tip (wing) stall?

I have found that too much elevator travel can cause a horrible stall on my planes. I have always used a little more elevator travel than is recommended in the plans. Well, I'm much older now and an unintended snap roll shocks the heck out of me now, plus my recovery is slower than it used to be. I am now using less elevator travel than in the past. Once I have tested and adjusted a plane, I will also give it full up elevator at various condition, including full level speed, but always 3-4 mistakes high. If it snap rolls I may reduce the elevator travel. It depends on the plane. What I don't want is an unintended snap roll at the wrong place, like TOO LOW. My Canard plane has scared the heck out of me in a high speed turning climb when it tipped stalled and ended up going the opposite direction and toward the ground. I saved it, but it shook me so much I had to land to figure out what happened. I also realized that knowing how close my plane is to stalling during a landing is extremely difficult since we fly without instrumentation. I therefor only land left to right or right to left, and touch down only near to in-front of me. I use the throttle during the whole landing process, plus elevator, the rudder and the ailerons, so I am always ready to recover from a stall. I crash very rarely. I also like to fly in high winds and gusting wind.
Old 01-26-2011, 07:40 AM
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Default RE: How to recover from a tip (wing) stall?

Rudder application is the best control when a model tends to roll or yaw during any time the current use of elevator calls for a higher than normal angle of attack. Get up some altitude and give it a try.

If you can train yourself to use the rudder for more roll corrections during the landing phase or take-offs, you will very probably not experience this "tip stall" demon during landing and take-offs.
Someone understands it is all about technique.

It is best to forget you have ailerons if you want to save a plane that has tip stalled close to the ground. The rudder is the most powerful control you have at low speeds, and gets more powerful as the airplane slows down.

A tip stall is the same condition a plane is in to do snap rolls. You may experience a half of a snap roll right at the deck. If so, be prepared to push down elevator to keep the airplane in the air once you stop rotation.

Rapid increases in power setting can start the problem when slowed down. Stay smooth.
Old 01-26-2011, 09:31 AM
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Default RE: How to recover from a tip (wing) stall?


ORIGINAL: TimBle

Ok I am going to knit pick here....snip snip snip
ORIGINAL: cfircav8r


ORIGINAL: TimBle

tip stall is that stall that occurs when the plane is in a bank and suddenly drops a wing tip resulting in a spin. This stall occurs because the weight of the aircraft has increased due to the radius of the turn being to tight. The wing can't hold the aircraft because its stall speed has been increased due to the higher weight. Recovery from the resulting spin...Everyone is of course correct about stall recovery for angle of attack related stalls.
Tip stall is a term used to describe an uncoordinated stall. That is, a stall in which one wing has a higher angle of attack then the other when it reaches stall. Correct thus far There are several ways this can happen, This is where it gets iffy a steep turncorrect, slow speed flight, Maybe but I'll come back to this later a high ''G'' pull up, Only where the plane did not enter the manuoevre from straight and level. In a high G pull up the wing stalls. Period. One wing dropping is a result of a wing weight problem on the airplane. Try it. Everytime you try a high G pull up the plane drops the same wing because that wing is HEAVIER. This is an aircraft set-up problem. The pilot has not balanced the aircraft laterally. This is NOT a TIP STALL, its a wing weight problem or any combination of these. In all cases the rudder is applied either too little or too much causing an uncoordinated condition and one wing to stall more. This can happen at any speed at or below, theoretically, manuevering speed (Vma) depending on ''G'' load or amount of uncoordination. A steep turn is the most common factor for both MA and FS.
In slow speed, you are correct, to aggresive rudder application can result in too rapid yaw which could stop a wing half instantaneaously resulting in a ''tip Stall''. That is a factor of slow air speed at the wing tip. Generally slow speed does not simply result in a stall because increasing the wings AoA will reduce the tendency to stall. AoA and airspeed are the contributors.

More on the high G pull up, if the planes attitude is not level pulling into the pull up i.e. the plane was not flying staight and level to begin with and one wing was lower or travelling slower than the other the result will be that once the plane is vertical it will be skew. The wing tip that is lower will drop first but the whole wing has stalled already. In these cases omne side is not more stalled than the other, they are both stalled. The stratic forces acting through the CG make it appear to be a tip stall but its not.
You are taking the term "tip stall" and applying it as if it is an aerodynamic principle. It is a layman's term used to describe any stall in which one wing drops first, generally an imminent spin, but not always. None of what I said is incorrect, a little glossed over perhaps, but correct, unless you believe the term only applies to a stall in a turn. Which it does not. As far as a heavy wing causing it, yes that is true but correcting poor rudder trim with aileron or vice-versa will appear the same. In all circumstances it is one wing having a greater angle of attack than the other, during a stall, that produces a "tip stall."
Old 01-26-2011, 11:50 AM
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Default RE: How to recover from a tip (wing) stall?

Usually a tip stall happens at the worst time, when you are low and slow on landing approach or after a take off without suffecient airspeed. The odds of having enough altitude to recover are slim. The best way to recover is to avoid the tip stall in the first place. Some will just accept that their particular airplane is prone to tip stalling and avoid the condition. 99% of tip stalls are any combination of the following 3 things.


1. Too nose heavy. hearing that a particular airplane is prone to tip stalling the pilot sets the CG further forward hoping to gain stability. The bad news is that it takes more elevator deflection at slow speeds and the stab is actually what gets stalled and airplane corkscrews into the ground.
2. Too much surface deflection. Many use too much surface deflection to begin with.
3. Pilot error, airplane just gets too slow and the pilot grabs more elevator to maintain slow decent.


There are a few more things that can be done to avoid tip stalling. Aileron differential is one. Building your airplane lightly is the best way to avoid tip stalls and once again although hard to beleive, a nose heavy airplane is just as prone to tip stallsas a tail heavy airplane.

The easiest way out of a stall is to neutrilize all control surfaces, build up speed and gradual pull out. You just need to have enough height
Old 01-26-2011, 07:48 PM
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Default RE: How to recover from a tip (wing) stall?

ORIGINAL: TimBle

Ok I am going to knit pick here....snip snip snip
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ORIGINAL: cfircav8r
Tip stall is a term used to describe an uncoordinated stall. That is, a stall in which one wing has a higher angle of attack then the other when it reaches stall. Correct this far
There are several ways this can happen, This is where it gets iffy a steep turn correct, slow speed flight, Maybe but I'll come back to this later a high "G" pull up, Only where the plane did not enter the manuoevre from straight and level. In a high G pull up the wing stalls. Period. One wing dropping is a result of a wing weight problem on the airplane. Try it. Everytime you try a high G pull up the plane drops the same wing because that wing is HEAVIER. This is an aircraft set-up problem. The pilot has not balanced the aircraft laterally. This is NOT a TIP STALL, its a wing weight problem or any combination of these. In all cases the rudder is applied either too little or too much causing an uncoordinated condition and one wing to stall more. This can happen at any speed at or below, theoretically, manuevering speed (Vma) depending on "G" load or amount of uncoordination. A steep turn is the most common factor for both MA and FS.
In slow speed, you are correct, to aggresive rudder application can result in too rapid yaw which could stop a wing half instantaneaously resulting in a ''tip Stall''. That is a factor of slow air speed at the wing tip. Generally slow speed does not simply result in a stall because increasing the wings AoA will reduce the tendency to stall. AoA and airspeed are the contributors.

More on the high G pull up, if the planes attitude is not level pulling into the pull up i.e. the plane was not flying staight and level to begin with and one wing was lower or travelling slower than the other the result will be that once the plane is vertical it will be skew. The wing tip that is lower will drop first but the whole wing has stalled already. In these cases omne side is not more stalled than the other, they are both stalled. The stratic forces acting through the CG make it appear to be a tip stall but its not.
I would like to add to this discussion.

Even for planes that are geometrically perfect, there is an element that messes any symmetry up: the propeller.

The spiraling slipstream that the propeller produces impacts each half wing and the vertical and horizontal tails from different directions.
Furthermore, for the same rpm's, the spiral elongates when the speed of the airplane is high and shortens when the speed decreases.
The left half wing "feels" a higher AOA, while the right wing "feels" a lower AOA; hence, the left half wing has a higher potential for stalling while the propeller is pulling hard.

Now, let’s combine these facts with a sudden pitch up movement and an opening of the throttle, like when leveling up at the bottom of a vertical dive or when climbing up fast at a step angle just after aborting a slow landing.
What happens during this maneuver?

The precession of the propeller generates a right yaw while the plane pitches up to rapidly increase the AOA of the wing.
Once that AOA is reached and sustained, the precession of the propeller decreases and the P-factor shows up, generating a left yaw (also helped by the vertical tail that is being pushed from th eleft side by the spiraling slipstream).

An opening of the throttle produces a reactive torque and left roll.
If that left roll and (higher load on the left half wing) is compensated with ailerons input (left aileron deflects down increasing the AOA), the left half wing approaches to the critical AOA even more.

Flight conditions in which a model is flying slow and at high AOA are not good for preventing a tip stall, even for models symmetrically built and properly balanced in both axes.

See some schematics here:

http://ma3naido.blogspot.com/2009/11...-reaction.html
Old 01-29-2011, 01:54 PM
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Default RE: How to recover from a tip (wing) stall?

The easiest way to answer the questions would just be to read text from full scale flying. I used to cite these books when I was a CFI full time.

Read http://www.faa.gov/library/manuals/a...83-3a-3of7.pdf for what to do when flying.

Read http://www.faa.gov/library/manuals/a...apter%2003.pdf for some theory behind the principles of flight.

Read http://www.faa.gov/library/manuals/a...apter%2004.pdf for aerodynamics.

Read http://www.faa.gov/library/manuals/a...apter%2005.pdf to learn about flight controls and their aerodynamics.

It will take a few hours to read, but I promise you, you'll have a whole new understanding of what you are doing as pilots and will get you to quit using the term tip stall, etc.

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