Friends didn't say, "See ya later" when I left for inverted flat spin training in Chandler, Arizona. They said, simply, "Goodbye." The editor sensed a liability problem and emphasized that this was not an official assignment. Did they know something? At that point, I was just like my little straight-and-level friends. That is, I wasn't sure what an inverted flat spin was, didn't know how to get into or out of one, and thought it might even be a stupid thing to do.
"There was a demon that lived in the air .... The demon lived at Mach 1," said the narrator in the movie The Right Stuff. In real life, Chuck Yeager not only found out where the demon lives, but rang the doorbell and introduced himself on a couple of near-fatal occasions. Does the demon also have a second home near the inverted flat spin?
If so, why go there? Debate has raged for years about spin training — not advanced spins, admittedly, just the plain-vanilla, ordinary upright spin. Is spin training the solution to stall/spin accidents or the cause? I concluded that knowledge is a good thing and that it is more dangerous not to know how to recover from a flat inverted spin. Also, since I practice aerobatics alone, the instruction seemed like cheap insurance. With the philosophical debate over, it was on to Chandler, where instructor and flight school owner John Walkup gave me two hours of instruction in the wildest spins I've ever seen.
Just as Dante's Inferno described several levels of hell, the world of spins has many levels of terror. On Level One is the stall — not a spin at all, but a close neighbor. Level Two is a conventional spin, while Level Three is an accelerated spin. Way down there at the bottom level, hidden among billowing clouds of smoke and guarded by fanged, blood-starved creatures, is the inverted flat spin. You can barely see it. The problem for the untrained pilot is that all of the levels are interconnected, with trapdoors leading from one to the other. Mess up a stall recovery, for example, and you could spin. Mess up a spin recovery and you could accelerate it — rather than stop it.
The good news is that in most cases the chain of events is easily broken by a properly performed stall recovery. And as the spin training course at Chandler Air Service demonstrates, it takes a lot of hard work to get most non-aerobatic aircraft into a flat spin, upright or inverted. It is therefore unlikely that you will slip into a flat spin by accident. Besides, many general aviation aircraft lack the performance required to perform such a maneuver. Cessna flight test engineers said recently that it is "virtually impossible" to flat-spin a Cessna 172. (The new Cessna 172 is not approved for spins of any kind, by the way.) Flat spins are best performed by an aerobatic aircraft that has the proper blend of power and high performance, such as the Pitts S-2B used by Chandler Air Service. And spins are best taught by someone as experienced as Walkup.
Walkup was selected as the local and regional flight instructor of the year in 1984, and he won the local award again in 1993. He also has a contract with the FBI to give a 10-hour unusual attitude course to the agency's 300 pilots. At a minimum, Walkup teaches a three-hour course — especially if the pilot has prior aerobatic experience, or has none and just wants a demonstration of the most frightening spin known to aviation. I signed up for only a two-hour overview, but Walkup said my previous 26 hours of aerobatic experience counted as the first hour.
"If a person with no previous aerobatic experience wants the three-hour course, I can basically give them an E ticket ride, increase their awareness, and expand their envelope," Walkup said. But he warns such students not to become overconfident. It takes eight to 10 hours for the student to gain an understanding of what is happening. "Until then, they have only learned it by rote," he said. His course uses aerobatics as a pathway towards greater understanding of spins and aerodynamics in general. Well, see for yourself.
Winch yourself down into the seat of the Pitts until your bones bend; it's time to fly. While spin instruction does not involve high G loads, it is a wild ride.
The first hour of instruction begins with aggressiveness training. Turns, even those to clear the area, are made with 60 or more degrees of bank, followed by a hard pull — precise and punctual actions needed by the pilot for what is to follow. Walkup then demonstrates that the Pitts can power out of a stall, even though it may be buffeting slightly, and can be maneuvered left and right to precise headings. Control at such a slow speed is heavily rudder dependent because there is little air flow over the ailerons, but the ailerons can still help. The purpose of flying an aircraft out of a stall — rather than diving until the aircraft is nearly supersonic, as some students do — is to assure minimum loss of altitude after a stall. Can his techniques save a pilot who has stalled and spun during a turn from base leg to final? No, there is little hope for such a pilot. Walkup's training is meant to teach avoidance of dangerous situations, not turn you into an Evel Kneivel of the air.
After aggressiveness training, it's time for conventional spins. Stall the airplane straight ahead, without losing altitude, and as it stalls, apply full rudder deflection. Spin one time before applying opposite rudder to stop the spin, and forward stick to break the stall. Bring the nose up quickly as speed builds, apply full power, and fly out near a stall. Assuming your stomach is still settled, climb back up, and let's try something else.
This time, take your hands off the stick after the spin has been achieved, but continue rudder pressure. The stick is more than willing to remain fully back, without any effort by the pilot. "Push the opposite rudder and stop the spin," Walkup says, and as the rotation stops, the stick pops forward as though on autopilot, doing what the pilot would do to break the stall. Now recover and climb back up. It is time for an accelerated spin.
An accelerated spin might be caused accidentally by a pilot who remembers only half the standard spin recovery technique — for example, getting the stick forward but forgetting to release rudder pressure. Enter another conventional spin, and after going through a turn or two, push the stick forward. You'll have to force it forward, and as that happens, the rate of rotation accelerates dramatically; the outside world literally begins to blur. Bringing the stick back again on Walkup's command slows the rotation to that of a normal spin. Recover and climb a little higher for the next maneuver, because it's on to the fun stuff; the next spin will be a flat, upright spin.
Let's try one to the left. Enter a normal spin for a turn or two until the spin has stabilized. Walkup has previously briefed you on what to do next; let's hope that you remember. This is the ultimate in distraction training — Walkup refers to it as maintaining a "presence of mind." As the spin develops, add full opposite aileron to begin the flat, upright spin. The nose rises slightly. Now, add full power. The nose comes up further to a nearly flat attitude, and the Pitts is spinning like a Frisbee, only not moving forward as a Frisbee might. The rate of descent seems to have slowed (a deceptive illusion that can continue until the aircraft is too close to the ground to recover), but the rate of rotation appears to have wound up to a horrendous speed.
If this were an amusement ride, parents would demand that it be banned. (In truth, the rate of rotation is about the same as that of a normal spin, but the nose — where the pilot's eyes are focused — is covering more distance in the same amount of time.) It takes lots of force to maintain full right aileron. That downward-deflected aileron on the left wing has dug into the air and is swinging the aircraft around as though the left wing has caught on something. The downward aileron has two to three times more drag than the upward aileron on the right wing.
"Emergency recovery," Walkup intones through the intercom. This is a technique that is especially useful for airshow pilots. Pull the throttle, which is in your left hand in a Pitts, back to idle, and when done, lift that hand into the air. Now the right hand comes off the stick; you look as though someone said, "This is a stickup." Now push opposite rudder to stop the rotation; it takes two turns or more to stop. If opposite rudder is released too soon, the spin will continue; if released too late, the aircraft will start a spin in the opposite direction. Rotation eventually stops — in the same amount of time as a normal recovery requires — and the stick pops forward by itself again. Now recover from the resulting dive.
Are you airsick yet? Probably. Sweat had soaked my back and started up the back of my neck when I called off the first flight, a warning sign that my stomach was counting down to a lunch launch. The over-the-counter air sickness medicine that I had taken prior to this was a mistake. Walkup suggested not using such medication again, and the first lesson was over. The main attraction, the inverted flat spin, would have to wait a day.
Day two, and if you're smart, you have eaten a sensible breakfast but have not taken an air sickness pill. Today's flight will consist of nearly all inverted maneuvers. First come inverted stalls. Roll upside down (this is where aerobatic training helps, but Walkup can talk you through it). Reduce the power to idle — remember which way that is? Simple things like operating the throttle — or just remembering your name — seem confusing when you're inverted. To stall, push the stick forward — since you are upside down — as speed bleeds off. The nose drops, forward pressure is released, full throttle is applied, and the nose is raised once again to the proper attitude to continue inverted flight. Stalling inverted and recovering inverted? Wait until the folks back at the office hear about that one.
But that's nothing. Next is the inverted spin. Roll inverted, stall the aircraft as before, but push full right rudder as the stall occurs. The aircraft begins to yaw as the nose drops, and it is especially confusing as seen upside down. From the back cockpit, the ground beneath the canopy moves right, but the nose is clearly moving to the left. That is why you must look over the nose to determine the direction of the spin. Something new has been added; the scenery is not only slipping to one side, it is also sliding upward. The Pitts appears to be tumbling, but that is just an illusion. As the spin develops, give up the quest for presence of mind and listen to Walkup; he still has his.
"Flatten it out," he says. Continuing with forward pressure and full right rudder, push the stick to the right (the same direction as the rudder) and apply full power. It has been said that the Pitts flat-spins faster than any other aircraft, and given the scene outside, who could argue? (Who wants to? Just get this thing down.) Daylight appears beneath the upside-down nose as it rises; and the spin flattens like a pancake. The scene outside is incomprehensible. The human eye can't focus fast enough to make sense of it.
Walkup calls for another emergency recovery. Power is reduced to idle, and now both hands are in the air; the foot opposite to the one that caused this problem is jammed against the rudder pedal. The nose drops into an inverted spin; but once again, it takes no longer than a normal recovery requires for the rotation to stop. Then it is a simple matter to recover from the resulting dive. The altitude was well over 4,500 feet when you started, but now it reads about 2,500 feet. (The altimeter was set to zero prior to takeoff.) You have dropped 2,000 feet in 10 or maybe 15 seconds (nobody was counting). Walkup notes with some amusement that the aircraft tried briefly to pirouette slightly on its wing tip before entering the flat inverted spin. Yeah, that's funny all right. After some aerobatics, just for fun, Walkup suggests heading back to the airport. In my case, I had long since forgotten which way it was.
The brief spin training program revamped forever my definition of unusual attitude, and that is a side benefit of what might be called extreme training. But learning how to avoid the situation in the first place is the real benefit. I'll be watching power settings and aileron position the next time I practice a spin on my own. Normal spins hold no fear for me now, and stalls are child's play. After all, I've seen the demon and lived.
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