39 votes

Low visibility spins and spirals: difficult-to-understand explanation of false perception

Your vestibular system can only recognize acceleration. Your brain combines that with visual inputs to produce spatial orientation. (If the two disagree, you may get motion sickness.) When you are in ...
StephenS's user avatar
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36 votes
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Can a helicopter really fly with rotors going this slow?

It's an illusion that the blades appear to be going slowly. It's actually a well known effect called the wagon wheel effect. Essentially the rotor is spinning at close to an even multiple of the ...
ratchet freak's user avatar
31 votes
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Are there any truly 'unrecoverable' situations?

One of the more common causes of crash and fatality is a low altitude stall-spin. A spin, in a modern aircraft, isn't of itself deadly -- with many designs, all you have to do it let go of the ...
Zeiss Ikon's user avatar
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29 votes

Low visibility spins and spirals: difficult-to-understand explanation of false perception

To enlarge slightly upon StephenS's answer, if the banked turn is properly coordinated, then the pilot feels only the G-force of the turn and no shear force in his or her seat, and concludes that (s)...
niels nielsen's user avatar
19 votes

Is it possible to perform a spin recovery in IMC?

I do not want to speak for civilian training here, and I do know that each aircraft has its own set of emergency procedures. Those procedures will depend upon the instrumentation that you have ...
Aaron's user avatar
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19 votes
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Is there anything extra required to spin a Cessna 172 in the Utility category?

Provided you meet ALL of the requirements for utility category operation as spelled out in the POH (within W&B limits for the utility envelope, no aft passengers, empty baggage compartment, and ...
voretaq7's user avatar
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18 votes
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Is it dangerous to do a skidding turn to lose altitude without increasing airspeed?

As Ron Beyer pointed out in a comment, your instructor was showing you a forward slip - a pretty standard maneuver for light aircraft. A spin would involve full rudder and a stalled wing, which ...
Dan Pichelman's user avatar
18 votes
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Does it really take 9000 feet to recover from a spin in a P-51 Mustang?

9000 feet is not likely if the pilot applied recovery techniques in a timely manner. US Army Air Force spin tests found here resulted in an average of 3000-6000 ft alt loss. There are several memos ...
TomMcW's user avatar
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17 votes

Is it possible to perform a spin recovery in IMC?

Entirely possible, although it is the turn coordinator not the artificial horizon that is primary -- to determine the direction of the spin. Nose-down elevator, rudder opposite the spin, the when ...
Ralph J's user avatar
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15 votes

Are there any truly 'unrecoverable' situations?

I'm going to make an assumption that solo student flights are in scope here, in which case I would say that flight into IMC (Instrument Meteorological Conditions) would quite often be unrecoverable. ...
GdD's user avatar
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15 votes

In a spin, are both wings stalled?

EDIT 9/14/22 Correct FAA answer: Yes, both are stalled. Reality: It depends For a steady state spin, the inward wing has to have less lift and more drag to sustain the combined roll and yaw motion. ...
MikeY's user avatar
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14 votes
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Why does spin recovery involve cutting the throttle?

Applying engine power can indeed help to end a spin. But the added thrust will make an overspeed in the ensuing spin recovery much more likely. Also, applying asymmetric thrust on the wrong side will ...
Peter Kämpf's user avatar
12 votes
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How does a nose down stall occur?

Does normal laws apply when the aircraft nose is vertically down? Yes, always. Physics doesn't care much about the aircraft's attitude and cannot be switched into different modes. While the nose ...
Peter Kämpf's user avatar
11 votes
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Is it possible to get into a spin situation while coordinated?

Yes, what you describe is perfectly possible. A stall in banked flight can result in a spin, given you fly the "right" plane. My first flight in an ASW-20C was late in the afternoon, when most ...
Peter Kämpf's user avatar
11 votes
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In a spin, are both wings stalled?

No, one wing has at least partially attached flow. How else would there be a rolling and yawing moment which keeps the spin movement alive? During a spin the aircraft experiences a linear variation in ...
Peter Kämpf's user avatar
10 votes

Is it possible to perform a spin recovery in IMC?

When I used to teach my IFR students, they usually spent only the first couple of hours with all of their instruments. I put them in all sorts of unusual attitudes and let them recover under the hood, ...
Shawn's user avatar
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10 votes

Does it really take 9000 feet to recover from a spin in a P-51 Mustang?

Sometimes a minimum density is needed to increase aerodynamic damping enough so ending the spin becomes possible. However, then there is not a fixed altitude loss to stop a spin but a fixed density ...
Peter Kämpf's user avatar
10 votes

Are there any truly 'unrecoverable' situations?

Generally, an airplane being operated within its published limits won't be able to get into a truly unrecoverable situation. (I'm specifically excluding the case where a recovery is theoretically ...
Nobody's user avatar
  • 200
9 votes

Can a helicopter really fly with rotors going this slow?

Life is full of illusions and many things give similar illusions. Strobe lights are popular with dance and and other entertainment venues. One game was to adjust the strobe timing so a spinning wheel ...
Gilbert's user avatar
  • 191
9 votes

Why does spin recovery involve cutting the throttle?

Several issues: Gyro precession induces pitch effects that may help or hinder depending on the direction of rotation P factor, which may help or hinder depending on the direction of rotation. ...
John K's user avatar
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8 votes

Why does the P-51 Mustang take so much altitude to recover from a spin?

Others can probably give you more precise info since I'm not a P-51 pilot, but I am studying aircraft dynamics in school right now, so maybe this will help. Many fighter aircraft are designed such ...
ryanrr's user avatar
  • 354
7 votes

Is spin recovery possible in an airliner?

In the sixties a Sabena Caravelle VIN entered a flat spin during a training flight. The crew demonstated stall recovery in different configurations when the plane entered into a spin by accident. The ...
Leo D'Hondt's user avatar
7 votes

Is it possible to perform a spin recovery in IMC?

Yes it is possible, but it takes more than training; it takes practice Point of reference/experience: Flight Instructor and Standardization Instructor, three years, US Navy. Caveat 1: I'd ...
KorvinStarmast's user avatar
7 votes
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Why aren't airliners spin-tested?

1. Spins are less frequent on large aircraft They are less maneuverable They are flown by more experienced pilots They have more protection systems (e.g. flight envelope protection, yaw damper) to ...
kevin's user avatar
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7 votes

Can you please explain aircraft spin in simple non-mathematical terms?

A spin is a kind of aggravated stall in which one wing becomes more stalled than the other one. This imbalance in lift results in an autorotative motion abound a vertical axis, generally passing ...
Romeo_4808N's user avatar
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6 votes

Is it dangerous to do a skidding turn to lose altitude without increasing airspeed?

I just want to go back to the OP's concern that rudder one way and aileron the other way is related to a spin - it's my understanding that this is a cross-controlled situation, and that is something ...
X Goodrich's user avatar
6 votes

Are there any truly 'unrecoverable' situations?

Let me go out somewhat on a limb here. student [...] looked terrified I'd say that any time you, the pilot, loses composure and/or situational awareness, that can very easily turn a normally ...
user's user avatar
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6 votes
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Does a skinless fuselage add to the likeliness of an unrecoverable spin?

Well, I would solve with transparent Monokote if it was a model. No accounting for people's taste. Although some very early aircraft featured that look, designers soon realized that covered "slab" ...
Robert DiGiovanni's user avatar
6 votes

Why don't multiengine aircraft have to demonstrate spin recoverability?

Because it would impose severe constraints on their design. Factors such as mass distribution make many twin-engine and multi-engine aircraft inherently resistant to spin recovery, despite the large ...
quiet flyer's user avatar
  • 22.6k
6 votes

What differentiates the entry procedures for spins and snap rolls?

A snap roll isn't a roll. It's an "enhanced" spin, done horizontally. A normal spin entered from level flight at 1G stall speed has an initial roll component along with the yaw component as ...
John K's user avatar
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