Last week I had my second aerobatic lesson in the Pitts. This lesson was devoted almost exlusively to spin training. Let me preface this story by giving you some background about my thoughts on spins. Maybe its my advancing age or maybe I am just not much of a thrill seeker to begin with? Whatever the reason, I have been very apprehensive during my aviation career to spin an aircraft.
Here is a good video by Sonoma Valley Flying Club showing what a spin looks like from the air...
Practicing power on stalls during primary training always made me a nervous wreck. I compare them to trying to hold a garden hose straight in the air while the water is turned on full blast! It always seemed very difficult to try and keep the plane upright while the engine was screaming full tilt and the nose was pointed seemingly straight skyward. To hold that attitude while waiting for the stall, and not dropping a wing drop and entering a dreadful spin while doing it put me on edge, to say the least.
I have a confession to make, one that got me flamed on the VAF forum, but whatever...don't get me started on the mentality of some of that crowd sometimes. I have practiced stalls solo only a couple of times during my primary training and never since then. Of course, I did plenty with my instructor and during my BFR...just not solo. My thinking went something like this. A spin is just an aggravated stall...i.e., an uncoordinated stall. I thought, if I badly botch a stall while practicing solo, I could enter a spin. I have read about how to recover from a spin in my training books...and yes, I have it memorized. But, even with that...I wasn't 100% sure I could keep myself together, not panic, and recover...maybe I was 99% sure I could pull it off, but not 100%. Consequently I didn't see the risk/reward for that 1% at this time....I knew how to avoid a stall and with my flying these days I stay in the center of the flight envelope, avoidance and awareness would be enough...for now. Ultimately though I want to be an aviator, not just an "airplane driver"....there is a big difference. An aviator explores all corners of the flight envelope with his aircraft....that's where I am headed.
Here is an analogy to illustrate my point. Lets say I come up to you and randomly put a gun to your head and say take one hand and rub your stomach and simultaneously take the other hand and pat your head (you remember this trick from your childhood as you've done it before...its not easy until you relax and concentrate on the task). And, oh, by the way...you have five seconds to do it or I pull the trigger. Some would pass that test fine...a lot would not. Why?...the pressure...panic sets in when percieved death is imminent and the brain shuts down. A great book on the topic of what the brain does in life and death situations is Deep Survival by Laurence Gonzales, highly recommend it.
If I entered a spin and the windscreen filled with spinning brown and I thought death was imminent (we always imagine it is closer than we think)...would I panic if I didn't have the training to recover?? I don't know?...for sure anyways. So...I vowed not to do stalls until I had spin training or was with someone who had. You can criticize that strategy all you want, but that was my approach and I stand behind it. I think all pilots should have spin training, its ridiculous to me that with the modern airplanes and instructors we now have that it isn't reinstated. Even without an FAA mandate, it is this pilots opinion that every pilot should seek out this training on their own. Especially as you get ready to be a test pilot in your airplane.
So, leading up to this day...you can guess how I was feeling, nervous would be a good word. Lets talk about "the spin". Its been known as the "pilot killer" since the early days of aviation. We've all seen the old newsreel footage of WWI biplanes spinning to their demise. As a kid, I devoured books about pilots and flying and they were always filled with tales of aviators meeting their end by way of the dreaded spin. Phrases like "he spun in" or "augered in" littered these books. Of course, with this kind of information rampant, I would have to come to the conclusion that spins are to be avoided at all costs while flying an airplane. Spins are the pilot's versions of the "boogeyman"...that mysterious creature that snatches pilots to their death if you encounter him inadvertently around a dark corner of the flight envelope.
My thought process for this lesson was not to smack the boogeyman around and show him who's boss--remember he does deserve respect, he's earned it. There are many aviators that have gone west because of him so I don't want to trifle with him. No, what I wanted to do, was meet the boogeyman...shake hands with him and see what he's all about. Is he as bad as they say?
A quick warning/disclaimer before I start the story. As I have stated before...don't try this solo until you get proper instruction. My account of spin training is just my opinion, I am not a CFI or a subject matter expert, so don't put your life on the line for anything you read on my blog. Also, I am doing spins in a Pitts S-2C...your airplane may be very different and consequently react much differently in a spin.
Before we flew our lesson, Dagmar and I did almost two hours of ground school a few days beforehand, on spins and other basic aerobatic maneuvers. I enjoy ground lessons...it helps me process things mentally before I fly. I like to understand the aerodynamics that are acting on the plane.
Simply put, a spin occurs when you are stalled and uncoordinated...BOTH must be present to enter a spin. This is why flying coordinated (i.e., ball centered), maintaining airspeed discipline and AOA awareness at pattern altitudes is so important. In a nutshell, don't fly sloppy...spin recovery at this altitude is not possible...all the spin training in the world wont help you down low if you enter one. I'm not going to go into the aerodynamics of a spin, but I encourage you to read about it here or in your favorite textbook on the subject.
We took off from APA and headed out to Kelly airpark. Once we arrived on site, Dagmar showed me the markers for the aerobatic box, which looked tiny. We would attempt to stay in the general vicinity so as to not aggravate the few residents in the area who don't like little red biplanes spinning over their house. Then we climbed high...our spins would start at 13,000 agl (remember its 7,000 ground elevation in this area). Plenty of margin so there is never a rush to pull out of the dive.
We started with some basics. First we did a power off stall to give me a feel for the plane. Ok, no big deal...nice buffet to warn you and no nasty wing drop as you would expect. Next we will do a power on stall...uh oh, my hands start to sweat. In the 260hp Pitts, a power on stall is, lets say...a tad "interesting". As you might guess, with such a high power/weight ratio, the deck angle was excessive by the time we actually stalled. In fact, on one of them (we did several) I was almost going straight up by the time it finally stalled. Dagmar joked, "that was almost a Hammerhead entry." :) Ok, all in all, not too bad...I can feel that I am becoming much more comfortable with unusual attitudes....definitely a good thing and I like it. I feel like I am taming the monster.
Next we do the "falling leaf" maneuver. If you've never heard of it, essentially you put the plane into a power off stall and hold it there with full aft stick. While falling, in a stalled condition...use only your rudder, keep the airplane upright and the wings level. Sounds easy enough, but it takes small, quick rudder inputs to keep those stubby wings parallel with the ground. I kept overcorrecting and was behind the airplane most of the time. But...the good thing is, I was decisive enough with my rudder inputs to keep it from entering a spin. I think my prior TW training helped with this exercise...I think nosegear guys/gals would have more trouble the first time because they are not used to using the rudder as much. The cool thing was, several times we went all the way to 90 deg bank and I was able to get that wing back up with counter rudder input. The lesson here...the airplane doesn't want to spin, you really have to force it to spin with control inputs, its actually spin resistant.
Ok, enough warm up...I want to do more of those maneuvers on subsequent lessons to practice but its time to finally face the boogeyman. The apprehension was pegged full tilt when I hear Dagmar utter the words I was hoping to avoid. "Lets do a power off spin." Crap! I thought about playing dumb and acting like I didn't hear her..."must be a malfunction with the intercom or my headset." But of course, I don't, and sheepishly respond, "ok."
She says, set up like a regular power off stall...as the airplane stalls, kick full left rudder...and hang on! Like ascending a roller coaster before the big drop, I could feel the tension rising as the airplane slowed and approached the stall. Once that happened, I knew it was "game on." Well, ok I think...as we do in bull riding when we are ready to turn the bull outside the chute...nod your head and say "lets go boys!" and let that baby explode into action.
Well...I feel the stall buffet and force myself to kick left rudder and over we go. My world has now started spinning. The first half rotation (incipient phase) isn't too bad as we slowly start to rotate and we are still somewhat upright. Then it kicks into the developed phase and things start spinning pretty quickly in the Pitts and the nose points down as the airspeed starts to build. Dagmar tells me to hold my initial full rudder to get a feel for the rotation, let it spin...around and around we go as the ground swirls past the nose. Focus on the cowling screw head, remember that's our sight point. If you look at the horizon, it will disorient you. Watch which way the ground rushes past the screw to determine your spin rotation (of course I know I am in a left spin on this occasion...but in an inadvertent spin, you will probably not be sure initially). Once you know your spin rotation, step on opposite rudder. Again, seems pretty simple, but there are countless aviators out there that have become disoriented in a spin and used the wrong control inputs. One way to do it is, if the ground is moving to the right with respect to the nose...step on the direction the ground is moving to try and stop it. For example, left spin...ground is moving to the right...right rudder.
Alright...opposite rudder...spin stops and then neutralize the rudder and pull out of the dive with a pretty aggressive 3-4G pull. I think I unknowingly held my breath for the entire maneuver! But...hey, I'm still alive...this is good. I hate to admit it, but it was actually kind of fun once I got past the initial terror. I have now been indoctrinated...I have spun an airplane. Cool.
Next we did some emergency recovery techniques. First we would do the Beggs/Mueller recovery. Enter into a spin....power to idle (remember to always do this first)...then release the stick. Yes, completely let go of the stick...not easy to let go of an 'out of control' airplane. Dagmar jokingly says, "massage your head with both hands." Then opposite rudder. Sure enough, worked like a charm as the plane recovered nicely.
Lets take it one step further and see what happens. This time, same setup...let go of the stick and ALSO take your feet off the rudder pedals...i.e., no opposite rudder this time to stop the spin. So yes, if you are keeping up with my description...I have no control inputs at all. The plane will do exactly as it pleases. I may as well be an infant child strapped in the seat along for the ride. Lets see how the old girl likes this?? Surely she needs my masterful touch to get out of this predicament? Hmm, the strangest thing happens...it once again stops spinning, all by itself, and recovers, nose down of course. Pull out of the dive and we're home free. Amazing really...this airplane (again, not all are the same) will fly itself into a stable attitude. This exercise goes a long way to putting my mind at ease while flying this wonderful airplane, I think I'm falling in love.
Dagmar was very adamant during our ground school about not only doing the correct control inputs for spin recovery but also the order that you do them. They are listed in order of priority. She didn't specifically use the acronym "PARE" during her ground school, but that is essentially what it was.
- Power to idle
- Ailerons neutral
- Rudder opposite of yaw (rotation)
- Elevator foward
So, Dagmar next wanted to demonstrate why each step is important...and consequently what will happen if you don't follow the plan and forget one or two.
Our next spin would be a flat spin. This illustrates why the first two items (power and ailerons) are important. She says, set up for a power on stall. As it stalls, kick left rudder and enter a spin, then full deflection right ("outspin") aileron (a definite "no-no" for spin recovery). These control inputs would be really easy to do if you panicked and weren't trained properly. Untrained pilots will usually try to lift a dropped wing with opposite aileron because it feels intuitive. Remember to always use your rudder, not aileron. The airplane spins up very quickly in this configuration and flattens out.
Moving on, Dagmar says, "next we will do an accelerated spin." Although technically this would be a spiral. Spins happen with a stalled wing...spirals do not. In a spiral, the airspeed will dramatically increase whereas a spin will show a slow, stalled airspeed. Again, set up for power on stall...break, full rudder to initiate the spin...hold full rudder and now slight forward stick...and hang on Johnny! You feel the airplane dramatically spin up in a tight rotation, their is some G-onset with this one and you are quickly screaming straight down in a corkscrew! Its an eye opener how fast this could get out of hand.
For some reason, like she just remembered, she says lets do an accelerated stall as a demonstration. Keep in mind, most inadvertent stalls are accelerated. Anything other than a straight and level power off stall usually falls into the accelerated version (i.e., any time we have more than 1G present). Stalls are directly a product of angle of attack (AOA), and AOA only...not airspeed, weight or bank angle. So many pilots don't fully understand this concept...educate yourself if you are unclear about it. The classic book, Stick and Rudder, is excellent teaching this concept.
There are several ways to do an accelerated stall in training...Dagmar wants to do it from a loop. Pull into a loop, and once we get on the backside and pointing the nose straight down in the vertical...full, abrupt aft stick. Bam! Sure enough, there is an airframe buffet and we enter into a stall and mush, still heading downward...remember, all this happened pointing straight down in case you think you cant stall in a dive. Easy recovery...release aft stick and we are flying again. This is a non-event in a training scenario but I surmise it kills a lot of unsuspecting pilots that become confused.
Paint this picture, you've done something to get yourself in a steep dive. Because your adrenaline is now spiked, you pull a little too hard on the yoke/stick because you don't like the look of that onrushing ground in your windscreen. The airplane stalls/mushes, but you continue on your downward path to certain death...so what is your reaction? Probably panic and pull harder to get the nose up...always worked in primary training right? Stick back...nose up, right? Well, not in this scenario. You end up yanking on the stick all the way to the ground, waiting for that nose to come up, and trust me it never will...not realizing you were in an accelerated stall all along. Try it with an instructor first so you know what it feels like.
Our last maneuver of the day was kind of a fun one, and was a great example of how maneuverable the little Pitts is. Dagmar says, enter a normal power off spin to the left. Once we get spinning, change from left rudder input to full right rudder. I do this, and the airplane stops spinning to the left...and starts spinning to the right...do it again to the left, sure enough we swap directions once again. Amazingly, the plane will do whatever I want it to do.
As we pull out of the dive, Dagmar is telling me something (I still cant remember what exactly?) over the intercom. Pulling out of the dive is kind of a high stress time...the ground is rushing up at you, you are loading up to 3 or 4 G's so of course the blood flow to the brain is also diminished slightly. All of this combined with a first time spin student and my instructor telling me to do something, was sensory overload for this ol' boy. Suddenly, Dagmar, stops her instructions mid-sentence and somewhat excitedly asks me..."what are you doing with the left rudder?!" In my mind, I think...not a darn thing. Then I realize I have been pretty heavily applying left rudder during the pull out and didn't have a clue I was doing it. I notice that it is enough rudder input to actually yaw the airplane. Wow, I think to myself, what a great lesson...a great illustration of what stress does to your brain. Part of mine had just shut down...and this was just training. How many pilots who are no longer with us, may have done something similar and snapped their tail off? Luckily I was in a sturdy Pitts and had an instructor to stop me from going any further. By myself, in a Skyhawk, for real...might be a different ending. Again...why I think the training is so important.
To sum it all up, I did a full one hour spin session and kept my breakfast down. I did, however, feel a little queasy once I got back on the ground. I felt like I had "sea legs" or had just gotten off a merry-go-round. As I've harped on several times, I think this training is invaluable, but remember spin avoidance at low altitudes is the primary goal. Being an aerobatic pilot or spin trained will not help if you enter a spin at low altitude. AOPA and the ASF did a very nice article on this topic if you want to read more about spins (one of the reasons I support AOPA with my membership dollars is stuff like this).
By now, you know my view on spin training, educate yourself and make your own conclusions about whether it's for you. I've met the boogeyman and he's really not such a bad fellow, you should meet him too...with an instructor of course, for initial introductions. Fly safe my friends.
Next lesson we do all of this...inverted! That's right, inverted spins...you up for it?!
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