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Nice summer day

Written by Vedran Sović.

Vedran Sović

 

“Something is wrong here” runs through my mind.

The aeroplane rolls sharply left, despite the yoke being held to the right. Nose is quickly slicing through the horizon and dropping low.

“Something is very wrong here”. That's the latest update of my situational theory. Quite belatedly, I manage to gather my wits: “You eejit! You have stalled your aeroplane and you are doing your darndest to push it into spin! Pull the throttle! Push the yoke! Don't fight the roll, follow it through!”.

Oh, it's better now. Aeroplane stops tumbling.

Looking forward, all I see is the forest.

It's the summer of 1996. I'll spend most of it doing my PPL course, on airfield Lučko and around it. The interesting part of the story begins when my instructor and chief instructor decided I'm trustworthy enough to be let loose in one of the practice areas. Up until then, I have flown twenty-something traffic patterns solo. Before I start enroute portion of my training, I need to get some more flight hours. I might as well do them in the practice area, a bit away from my instructor's sight.

For my first solo flight out of traffic pattern, I got assigned to the practice area Horvati, just a bit south of the airfield. My instructor has led me on the tour of all practice areas around our base, so finding it should be no problem. Maneuver repertoire remains the same, the only difference being I'm now alone. Get to the centre of the training area. Choose some landmark to fly your maneuvers along. Make a couple of clearing turns, checking all round to see that someone hasn't wandered into your area. Be careful not to wander out of your assigned area. Start with turns: left-right. Now steep turns: left – right. Slow flight, with minimal speed, only slightly above stall, now do some turns while flying slowly; left-right. Stalls.

A few words on the topic of stalls: aerodynamics theory tells us about the airflow separation, that the stall can happen at any aeroplane attitude or at (almost) any speed. Quite simplified explanation, relevant to the case we have at hand: stall is when the airspeed gets so low the air(flow) can no longer support the weight of the aeroplane so it starts falling. There is also a pretty troublesome variation on the stall: spin. It occurs when one wing gets stalled before the other; aeroplane rolls and yaws towards the more deeply stalled wing and spiral plunge towards the planetary surface ensues. To recover from spin, one primarily needs a lot of altitude. Recognition that the spin is developing (or has developed) is also essential. Spin recovery (usually) requires a bit of counterintuitive piloting; aeroplane is falling with nose low, yet the yoke/stick needs to be pushed forward, in order to break the stall. I did all my training up to PPL on Cessna 152 and if this cute little aeroplane has a flaw, it's its very docile behaviour. Someone believing that all the aeroplanes are flying like 152 might be in for a nasty surprise when switching types. A couple of months after my (mis)adventure, I'll do some intentional spins on it. Even with full pro-spin control deflections (yoke fully back, rudder fully in the desired spin direction) left spin would self-recover after a turn and right spin was quite difficult to provoke. As usual, there is a catch: 152 spins benignly only with power off. At full throttle, the propeller slipstream will happily force it into the left spin and bury it there.

So, the last item on the day's agenda is the stalling practice. Power of stalls comes first. Aeroplane is slowed down in horizontal flight, flight controls are becoming increasingly “mushy” - lighter and less effective, that is. Stall warning horn toots a few knots above actual stall speed and I pull the yoke. The aeroplane pitches up slightly and here comes the stall – nose drops despite yoke being pulled back. I release the pull and add power. So far so good. Now there's only power on the stall left. Purpose of the exercise is to simulate stall during too steep climb after take off. I turn towards the centre of the practice area. Altitude is OK, throttle idle, speed drops. Here comes the stall warning horn. Full throttle and pull on the yoke. Now the prop pull pitches up more than with power off stall, yet the aeroplane stalls pretty quickly. Nose pitches down but there is also a hefty roll to the right. No problem, I have seen this on my flights with the instructor. I know what to do: push on the yoke and roll to the left. When the stall is broken, roll right to get the aeroplane upright again. I'm flying normally again, exercise over... except it occurs to me that it's the largest roll I've seen so far. I have some time left, I'll try it again, hoping it will turn out neater. Same story. Let me give it another shot. Even today, I have no clue why-oh-why on the third stall attempt I didn't push the yoke and rolled to the left but tried to pick up the dropped wing by commanding the right roll. So I pushed the aeroplane into spin. My first spin. On the first solo flight away from the traffic pattern.

Things are getting more complicated presently. Loss and (slow) recovery of situational awareness were so perfectly timed that I recovered from the spin after half turn. Later I'll read some spin theory, explaining why spin recovery should be either done within the first quarter of the turn or after the three quarters and never after half-a-turn. It's time for me to learn it the hard way.

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There's the episode of the fantastic BBC's documentary series “Reach for the skies” where Chuck Yeager explains that flashbacks that pilots are supposed to have in critical situations are pure Hollywood fabrication. All the pilot in the tight spot thinks about is how to get out of it. Well, he is right. Spin has stopped and the first thing in my mind are the words of my Instrument flying theory professor: “When recovering from nose low unusual attitude, first roll the aeroplane upright, only then pull.” Great plan, so let's see, what is the inclination of my plane? Where is the horizon? Can't see it through the windscreen. Quick glance to the left and there it is, perpendicular to its common position. Great. I managed to stand the aeroplane on its nose and I'm now diving vertically. On one hand, it makes my job easier; there's no bank, just pull. On the other hand, 90° pitch change is a long way to go. No time to waste, I pull. Horizon is appearing on the top of my windscreen. Blue replaces green until they are at their usual positions. Aeroplane is now flying horizontally and I'm pleasantly surprised I have recovered reasonably quickly, so the speed is within the green (normal operating) arc and there is more than 1000 ft vertical separation between me and treetops.

Time for the emotional reaction to a just performed bizarre aerobatic figure. Fear? Nay, it would be insufficiently paradoxical for my taste. I am angry with myself for being unable to perform such a simple maneuver to my satisfaction. Full throttle, climb towards the center of the practice area. I try two more power-on stalls. There is still wing-drop but it's getting lesser. Now I'm content. Time to go back to the field. I report I'm done and ATC lets me join the traffic pattern for landing.

The penny drops.

Only then I realize what actually happened and that the story could have ended in a nastier way. Hot summer day turns chilly in a moment. I'm not shaking... excessively. It's all right, I got out of the mess, all I need to do is get the aeroplane back to the airfield. Joining the pattern on downwind. Base turn. Final turn. I can make it over the creek and onto the field, even if the engine quits. Normal landing. Get off the runway. There's plenty of fuel left, so I'll park in the grass, next to the taxiway. Mixture cut-off. Prop stops. My colleague approaches the aeroplane, quite enthusiastic about having his turn to fly. Then he sets his eyes on me and his smile fades so rapidly that I have no doubt I look awful and, even If I had any idea how to pretend everything was fine, it just won't work. I open the door. “What happened?” I confess everything. He suggests I should have a word with our instructor. I accept the suggestion with gratitude and we walk across the apron to our group. Afterwards, I was told that I got so pale-faced it looked as if the ghost was walking on the airfield. Same question from our instructor: “What happened?”. So I repeat the story, as much as my holed memory allows. I expect criticism of my ham-fisted piloting, yet our instructor is quite content I made it out of the self-inflicted predicament. Anyway, it would be better for me to take the rest of the day off, while the mechanics check the aeroplane. It turns out that my impromptu airshow didn't result in anything broken or bent, so my fellow students go on flying and I'm going home. Till tomorrow. Till the next, better, flight.

Later in my training, I performed some intentional spins, including those on Zlin-142, that have positively vicious spin characteristics, yet the first one still remains the only unintentional. I'm keeping my fingers crossed it remains so until I retire.