Lesson 2

This time we’ll do right-hand spins, right aileron rolls, and then loops again, mostly to tighten things up, and to get me more used to it all. Again, we start in front of the whiteboard; Ben discusses how to improve what I was doing last time, then goes through the medical aspects of aerobatics, especially the various +ve and negative G force effects and symptoms. After 10 minutes of this I get a much better appreciation for what the average competition aerobatics pilot goes through — I find 4G’s uncomfortable now, but what’s that compared to +12 G’s or -6?! I don’t know, and don’t want to find out. We go through some of the formal aerobatics figures or diagrams used for competitive maneuver descriptions (if you want to see what real aerobatics competition sequence diagrams look like, check the 2003 Knowns from the IAC Chapter 38 website), then discuss the use of call-outs: at the start of each maneuver I should check and say aloud the current altitude, airspeed, and the maneuver to be performed, all as a last-second sanity check.

We head out towards the practice area, and I brace for more disorientation. But right from the first spin to the last loop I do, everything feels fine today — no disorientation, no loss of energy, no nausea. And not just fine, but really enjoyable. Keeping my camera stowed and concentrating on the airwork seems to make all the difference, as does drinking from my water bottle(s) every few minutes.

We start with right spins, which are a lot harder to get going than left spins (for all the usual reasons to do with torque, etc. that make right steep turns harder than their left turn equivalents in a 172). But once they start, they feel more dramatic to me — we seem to be heading straight down this time, and spinning at a higher rate. But I love it! So we try right aileron rolls. Again, these are harder to get started than left rolls, and a lot harder to keep going (at least in the Aerobat), but I keep at it and get the hang of it pretty quickly. The feeling of just having the world slowly rotating around you like that gets pretty addictive very fast.

This time we try loops with me just keeping my view forward — no sudden turn to the left as you’re supposed to do when you’re level. It seems to work, and in half a dozen or so good loops I don’t feel disoriented or discomforted by the G forces at all. Again, it’s suddenly a lot of fun — the float at the top of the loop when you look “up” at the ground is way cool, as is the G force in the final pullup. But a real danger here with loops in the Aerobat, though, is the tail slide. This where you don’t keep enough forward airspeed in the pullup, and the plane slides backward through the air, with potentially catastrophic effect on the elevator and other control surfaces in aircraft not strengthened and certified for this maneuver. It’s easy to avoid, and if you recognize that it’s about to happen, not too hard to recover from with rapid control movements. Ben’s briefed me on this, but I don’t want to ever have to do this in 36B.

All through these maneuvers, I’m still having trouble with positional and attitude awareness — especially during the spins, I can’t keep track of how far we’ve rotated, or (during the rolls and loops) what our attitude really is without thinking about it. To do this properly you have to develop a good subconscious peripheral vision (among other things), and be able to fly it by the seat of your pants (as my Grandfather would say). I still need Ben calling out the attitude and / or control input for smooth maneuvers, but even when he says nothing at all I can at least get the basics right, if a little rough.

I’m also still having trouble wrestling the yoke with enough force, and with my elevator and rudder usage. The yoke forces, and pushing things to the stops, still feels unnatural, but I suspect I’ll get it pretty soon. It certainly made a difference in the right aileron rolls, where I tended to barrel out of the roll due to simply not pushing the yoke over hard enough, nor keeping it there. I’ll learn. Rudder usage was also a bit rough, but nothing that’s yet cause for worry. And I forgot about every second callout, but that’ll come in time.

The main lesson from today was, again, that I can do this, and — this time, at least — it was turning out to be a lot of fun, and without the damn camera, disorientation and discomfort was no factor at all. Looking straight forward on the loops seemed a good idea, but next lesson I’m really going to have to try to look left.

The Cessna Aerobat

In the US, any aircraft used for intentional aerobatics must be certified for each individual maneuver (like a hammerhead stall or a snap roll) you intend doing. The club has only one plane that’s certified and suitable for aerobatics — N7336B, a snappy little Cessna Aerobat with the Texas Taildragger conversion. 36B is certified for all the basic +ve G maneuvers (barrel rolls, aileron rolls, snap rolls, loops, Cuban Eights, spins, etc.). Apart from being a club member, you need to have a tailwheel endorsement and the owner’s sign-off to be able to rent or fly PIC in this plane, so you can’t just hop into it and fly off, but — as someone who got his tailwheel endorsement and sign-off last year in 36B — I strongly believe it’s worth learning to land this plane anyway (it usually changes your perspective and landing skills for the better in any aircraft…). In any case, you can still do aerobatics or unusual attitude recovery instruction with a suitable club instructor in this plane, even if you’re not interested in getting a tailwheel endorsement.

The Aerobat’s good for basic aerobatics training — it’s relatively docile and safe, it’s much stronger than the standard C152, it’s certified for the standard -3 to +6 G stresses, it has four-point harness belts suitable for aerobatics, and, unusually, it has side-by-side seating. This may sound unimportant, but it’s much easier to follow what the instructor’s doing — or vice versa — with this arrangement than with the more common fore-and-aft seating in the Pitts or a Citabria. Plus it has a yoke rather than a stick, which may sound less glamorous, but in fact helps a lot for those of us who may never have flown a stick before. It also differs from more hardline aerobatics aircraft in having a relatively-full panel, with the normal complement of gyros (AI, DG, and TC). These instruments are not useful in aerobatics, and, in fact, usually tumble, go belly-up, or start spinning uncontrollably after the first maneuvers (which is a lot of fun to watch when it happens, I have to admit). The average competition aerobatics plane usually has little more than a compass, altimeter, ASI, and engine controls — and that’s all it needs. Just don’t run it into a cloud layer.

The only real downside to learning with the Aerobat — and why you can’t do more than fairly basic training with it — is that it can’t do negative G maneuvers for more than a second or so (it has no fuel pump, so the engine stops pretty damn quickly…), it doesn’t have a constant speed prop (which comes in real handy when you’re trying to keep the RPM’s constant through wildly-varying airspeeds and attitudes), and it’s relatively underpowered. Climbing back up a couple of thousand feet after a set of spins with two people on board seems to take forever, at least compared to something like the Pitts. All in all, though, 36B’s fun to fly, aerobatics or not — it’s my main solo local flying aircraft now.

Lesson 3

Immelmans, Half Cubans (great name…), and just generally sharpening up loops and aileron rolls. This time I’ve dragged along my Sony Pro DV video camera; it makes me feel even more like a damn bumblebee with the associated harness and pack, and I can barely climb into the cockpit with it and my parachute attached. Of course we’re being watched at the fuel pumps while I try to get into the left seat, and I start to think I’m actually going to fall back out in front of the audience (some aerobatics pilot he is!). I make it, but it’s a close thing. And I’m neither tall nor particularly big in any way — how would someone six inches taller than me or (say) 50 pounds heavier do this?!

After the usual whiteboard discussion and a digression into the various types of aerobatics aircraft, we depart for the practice area. It’s a gusty day on the ground, but nicely smooth and sunny over the Central Valley and Delta. We start with a few “straight” loops, with me looking to the left this time. These work well — no disorientation at all, and I’m much better at getting aileron, rudder, and yoke forces right (but still a bit rough).

We try Immelmans, and from the first this is “obvious”. Immelmans are where you roll straight and level off the top of a loop, a maneuver developed during WW I for quick altitude gain and for getting away from pursuing fighters, etc. (it wasn’t actually developed by Immelman, but that’s another story…). I’m rough, but in general the Immelmans nearly all work fairly well, and make me feel like I’m actually “getting” (very) basic aerobatics now.

Then the Half Cubans (read the Szurovy and Goulian book cited below for an explanation of the name. Likely story). These are like Immelmans except you start the roll later, so that you roll wings-level in a dive after the top of the loop. Putting two half Cubans together gives you a full Cuban Eight — a vertical figure eight. Cool! I’m up for it… and so it goes. Half Cubans seem somewhat obvious as well, and again, although I’m rough, we don’t fall out of the sky, and Ben doesn’t start screaming “we’re all going to die!!!!” at all this time. This is really enjoyable.

And something’s slowly happening here: unlike the last two lessons, I’m generally aware of when our heading’s off on coming out of a roll or loop, or how many rotations we’ve done in a spin, or what our vertical attitude is in a loop. It’s still only a rather rough idea, but I do seem (finally!) to be developing the peripheral vision and associated attitude and positional awareness that’s essential for decent aerobatics.

At the end of the lesson I pull out the video camera and get Ben to do a few spins, loops, and rolls, just to test the concept and see how well I cope. This time, the disorientation and discomfort comes on slower than the first lesson, but I still have to stop after about 5 minutes. This is depressing, but not surprising, I guess. I have a lot of practice ahead before I can do this comfortably. We head back to Oakland, with me feeling very mixed about it all: the actual aerobatics parts are going well, and I’m enjoying them immensely, but the photography and video bits are turning out to be more of a problem than I’d hoped. I suspect this will get better with practice, but I’m not certain yet. [Click on the image to the right to see a video I edited up of the lesson in Quicktime video format. Warning: the video may be only a couple of minutes long, but it’s not small — 25Mb — and if you’re running a Windows box you may need to download a free Quicktime player from Apple].

* * *

When I get home there’s a flyer in my mailbox from the FAA inviting me (and, no doubt, thousands of other Bay Area pilots) to an “Unusual Attitude Recovery Training” Wings seminar out at Tracy sometime mid-April. It’s being given by Cecilia Aragon, Ben’s aerobatics instructor, and local Berkeley legend. Tempting to take 36B out there for the evening.

Preparation

Do you have to do anything special to prepare for aerobatics or for the lessons themselves? Most good aerobatics pilots will probably claim that it’s all in the preparation, and that’s mostly true, but if you’re just going off to practice aileron rolls the preparation is definitely not going to be quite as rigorous as competition work.

In my case (and ignoring the photography side of it), I tend to concentrate on two main things: thinking my way through the maneuvers, going through the details of things like throttle control, yoke movement, rudder positions, likely views through the windshield, etc. at each step of the maneuver; and preparing physically so I don’t feel under par when I’m inverted or spinning wildly. In other words, I don’t really do anything special to prepare, but then I’m not doing competition work.

For the physical side, I really just do the usual pilot things — avoid the obvious pitfalls — and ensure that I’ve eaten well (not too much, not too little) two or three hours before aerobatics, and that I have sufficient water to drink while flying (about a litre — Americans, think “quart” — usually works for me). Aerobatics on an empty or full stomach, or after a greasy meal, sounds like hell to me, but then this is a very individual thing. I also take a bunch of Aspirin for possible headaches, and tons of sunscreen. Other than that, nothing special.

Thinking through the maneuvers, though, is a bit different: I tend to be a little obsessive about it, sometimes finding myself in front of the TV having missed large swaths of a program because I was mentally running through an Immelman or a Cuban Eight or whatever. A sort of Walter Mitty thing, I guess, but TV affects people in mysterious ways….

Lesson 4

Reverse Half Cubans, barrel rolls, wingovers, and just generally tightening up the maneuvers I’ve already learned…. I wake up with a headache and wonder if I should cancel, but after a coffee and chocolate croissant at JavaRama I feel better. But it sort of sets the tone for the rest of the day — I do a lot of things only half-right, with a bunch of sloppy flying, leaving me irritated at myself. It starts early, on departure, when Tower calls traffic for us over the Temple, and I misidentify it — and pass rather too close to the traffic she’d actually called just above us. There were two aircraft over the temple….

Out at the practice area we do a couple of aileron rolls to see if I can remember what they were all about. Well, yes, I remember what these are — but halfway through the first roll I just … blank out a bit… and forget to use the rudder properly and don’t keep the ailerons fully deflected. I mush my way through the roll, thinking maybe I’m not entirely here. I’d return home instantly if I didn’t have Ben to take over if I make a mistake.

So we try barrel rolls. Barrel rolls are a classic combination of a loop and a roll: start as for a normal loop, pitch up to about 60 degrees, then slowly roll with back pressure all the way back out (and watch the throttle!). At the top of the loop your heading should be about 90 degrees off where you started; at the end it should be the same, of course. Ben does one, then I try it. First time around, not too bad — very rough, with the wrong heading on exit, but I’ve got the idea. We try another, and I get the hang of it pretty quickly. And hell, these are a lot of fun….

And then the Reverse Half Cuban (cool name). These are really nice when done properly: pitch up to about 45 degrees, roll inverted, pull out of the loop in the opposite direction to which you started. Easy, no? Well, the first time I try it I blissfully continue on with the roll way past inverted in another of these slight blank outs — what the hell am I supposed to be doing this time? — and just keep going on instinct, barrelling back out in a sort of slow aileron-roll-meets-squashed-loop sort of mess. D’Oh! Maybe the coffee wasn’t enough after all. The next attempts are better, but I still find it hard to judge the inverted point and attitude accurately: if you miss this, you tend to barrel out (as I did), or the loop becomes pinched or flattened. Still, these are really enjoyable, and you get a sense of more complex aerobatics than just a plain loop or roll (no, I’m not jaded, not yet). I could do these all day…

But I should be learning the classic wingover, a slightly more dramatic version of the lazy eights I’ve occasionally done with John or Jeremy while doing airwork practice. Wingovers are the ultimate box canyon maneuver — a steep 180 degree turn with no altitude loss. These come naturally, but the first couple I try I’m way too rough — this should be a gentle, smooth, relatively low-speed maneuver, but I keep tossing the plane over too quickly and treating the whole thing as though I’m about to dive at a bunch of targets on the ground or something (shades of Walter Mitty again). This and the barrel rolls are the first maneuvers where I haven’t had to use full aileron deflection, and the wingover doesn’t need much throttle either (unlike everything else we’ve done), so my general lack of finesse shows. I’m just not a subtle kind of guy, I guess.

The headache is coming back with a vengeance, so I get Ben to do a bunch of loops and slow(ish) rolls while I get out the camera and shoot. This goes well (no disorientation at all), but it’s clear that I need the wider (but much heavier) lens I used the first time, and the results aren’t particularly interesting. At one point Ben — doing what I’ve just asked him to do — maintains us inverted at the top of the loop just enough to feel slight -ve G’s. I nearly lose the camera “up” just as I’m moving it in towards my body. I need to strap the damn thing to me much better next time.

Returning to Oakland over the Diablo Valley we see a 172 doing intentional spin practice over the Danville / 680 area, maybe 5,000′ up. This has to be both stupid and illegal — right over a congested built-up city, in the middle of some heavily-used approach and departure routes (not to mention the whole Diablo Valley corridor itself), and very near a bunch of airways (and maybe even in the Class B). But it did look dramatic….

The whole not-quite-here syndrome continues on landing: I do a really smooth three-pointer on 27R, but I grease it in too quickly (no stall to speak of in the flare) and forget to hold full back pressure on rollout. It would have made a pretty decent wheel landing, but I just didn’t have the presence of mind to change just before the flare.

On the way out to the parking lot I run into Lou sitting at a table in front of his office doing paperwork. I haven’t told him I’m doing the aerobatics thing, but someone has (Liam? Ben?). He smiles up at me and says: “Aerobatics in a 150?!” But he has the grace to admit it’s a good aerobatics trainer — “you really have to work to get that thing going”. True enough. But his Pitts looks ever more inviting to me these days, I have to admit.

What Will I Do With All This?

What will I do with this training? Friends have sort of assumed I’ll start wearing scarf and goggles and go off barnstorming competitively, but I have no intention of doing competition-level aerobatics (way too much discipline and punishing physical effort involved for this couch potato). There are several things I had in mind when I started, though: firstly, to be able to better cope with unintentional aerobatics, like finding myself inverted after hitting bad wake turbulence, or entering an inadvertent spin. Secondly, aerobatics is just fun — I want to be able to strap on plane and parachute and go out and just loop or roll or spin the plane periodically just for the hell of it. It’s great recreation. Thirdly, and although this really didn’t cross my mind when I started, I’d like to do more aerobatics photography, especially from with the aerobatics plane itself. This is a good entry in to that, if I can get the time to pursue it further.

Lesson 5

More loops, aileron rolls, spins, and Immelmans to get back into the swing of things… then slow(ish) rolls and full Cuban eights. Ultimately a lesson in how not to panic when things go wrong, and what (emphatically) not to do when you’re upside down or the bottom (or is that top?) is falling out of a Cuban (this just cries out for a punchline, but I haven’t the wit).

At first it all goes well — I’m a little rusty, but the loops, aileron rolls, and spins seem almost second nature to me now, and if they’re a bit rough, that’s just a matter of practice. I’m more comfortable than ever now with pulling (positive) G’s, and attitude awareness in everything but the spins seems to be developing nicely. And even the Immelmans go OK, with a bit of prodding from Ben. And then we try the slow(ish) rolls…

Unlike aileron or barrel rolls, the aim of a true slow roll is to keep the plane’s longitudinal axis pointing in the same direction throughout the roll. This is a lot harder than it sounds, especially when the plane is at knife edge, i.e. flying with wings vertical in the 90 or 270 degrees position. In any knife edge manuever, the only things producing lift are the fuselage and the engine — and we all know a typical 152’s engine isn’t going to help here. Luckily the fuselage on the Aerobat can produce a surprising amount of lift, but the reason we call these “slow(ish)” rolls is pretty evident the first time around — you just can’t keep the longitudinal axis completely straight, and nor can you avoid losing a fair amount of altitude in the Aerobat; you also can’t do it too slowly without losing engine power due to fuel starvation in the inverted segments. So you have to compromise and keep the roll rate fairly high and the axis just more-or-less on-heading. Oh well. But the combined rudder, elevator, and aileron work required to keep the plane going smoothly through the roll is a real test of coordination and forethought. At knife edge you have to use the rudder as an elevator, the elevator as rudder, etc., and what you have to use to keep the plane straight as it revolves through 360 degrees changes quickly through each quadrant. Quite a workout, and a real lesson in being able to separate out the actual dynamic effects of each control from their usual function — and learning to override your instincts to coordinate them the way you would under “normal” maneuvering conditions. I don’t do too badly (and the engine only hesitates once), but by the end of four or five complete slow rolls, my brain feels like it’s about to explode with the effort (I start wondering whether I’ll ever be able to do a plain boring old coordinated turn again without thinking about if for five minutes…) and we push on to the full Cubans…

The full Cuban Eight is the tipped-over figure eight that results when you do two half Cubans one after the other, and if you’ve done a bunch of half-Cubans (like I have), it sounds pretty straightforward — just connect the dots. What could go wrong? Lots, especially if you’re momentarily distracted and haven’t internalised inverted flight yet. Things come (almost literally) unstuck for me very quickly on the first attempt: over the top of the loop, inverted, before rolling back to “normal” in the dive off the top, I let the plane go into near-negative G’s. This in itself isn’t too bad for a loop — but instead of letting it float through the loop as-is, I instinctively pull back on the yoke to correct for this. The plane quickly starts an inverted dive towards the ground at a high rate of knots, almost a Split-S. For the first time in many lessons Ben grabs the controls, and rolls us out the maneuver before we get too fast and exceed Vne in a real Split-S. Urgh. I feel really stupid, but Ben points out that this is a classic thing to do inverted when you’re still learning. Unfortunately, pulling back while inverted is about the worst thing you can do in this situation unless you’re also prepared for a sudden recovery at high speed — but it’s the natural thing for a newbie aerobatics pilot like me to pull back. But you’ve got push forward here to keep things under control…

A couple of more-successful Cubans later, I screw up again. I roll too slowly in the dive — in fact I pretty much stop rolling at about the 90 degree point — and once again we start falling out of the sky in an inverted dive. And once again Ben takes the controls and rolls us out of danger. And once again my instincts were wrong — again I pulled back. What should I have done? I should have pushed the ailerons hard over and rolled out of the problem. Again, a classic lesson: when accidentally inverted (or, as in my case, almost inverted but not meant to be more than momentarily so), most people’s instinct is to pull back on the stick; the best thing to do is almost always to neutralise the elevator (or push it forward) and start / keep rolling back to upright.

The next few maneuvers go OK as I internalise this, but it’s a sobering thing, and I end up just doing a few desultory photos and heading back to Oakland fairly quickly. Oh, and my landing was dreadful.

Quite a lesson. When I get back I feel a bit chastened, but in general still pretty good about the day — I learned a lot about (not) panicking and what to do in such a situation. I’m fairly confident I’ll internalise this lesson very quickly, but we’ll see…

Author’s Note: Continued (more or less, and after a year’s absence) in blog form at Yankee Alpha Foxtrot Bravo.

Notes & Links

Some notes on photography and video work during aerobatics (much of this is probably pretty obvious if you’ve done this before; I hadn’t…):

• The inside of an enclosed cockpit is just full of shiny things, reflections off windows and windshields, etc, and it’s almost impossible to get rid of this, even with decent polarizers. And since you’re doing aerobatics, the reflections and shadows change and move quickly in ways that are difficult to predict. I’ve just learned to live with this, and Photoshop the worst of it out later. I also use a large home-made lens shade that can be pressed up against the windows.
• To get dramatic still photos from inside the cockpit, you really need a good recognisable on-plane reference like a wing, panel, cowl, etc., in the shot to give the viewer some idea of the relative angles of the ground and the aircraft. Shooting out the side windows, this is easy, and even a medium-wide angle lens like a 35mm (35mm format equivalent) will get the wings and / or wing struts (if they exist) in nicely. Looking forward, though, you need a decent wide angle, at least a 28mm equivalent, more usefully a 24mm or even 20mm, to show the cowl or panel as well as the horizon. This will vary from plane to plane, of course, but I’ve learned to drag along my 17-35mm zoom (24-50mm in 35mm equivalent terms on my D100) to cover all the situations.
• Use a good zoom lens. Changing lenses in an aerobatics plane just isn’t easy — you have to be flying straight and level(ish), and you can’t ever let a lens loose… in any case, the small optical imperfections you tend to associate with zooms over primes isn’t a factor when the windshields or windows are so optically bad anyway.
• The plastic front and rear windows on a plane like the Aerobat are really very bad for shooting through. They have a strong color cast, are very reflective, and have some fairly obvious optical distortions that make sharp hi-res images very difficult to do. Plus they get bugs and dirt on them every time, in exactly the worst possible spot, no matter how many times you clean the bloody things before you take off (Ben’s a little obsessive about cleaning the windshield).
• You absolutely have to be able ensure that the camera (and associated gubbins like lenses and filters) won’t come loose or — much worse — actually fall out of the plane when doing aerobatics. In an open cockpit, make damn sure the camera has several straps tying it to you or the airframe; and, even in a closed cockpit, make sure it can’t just fall out of a loose bag or something and run around loose. A camera can do a lot of damage when it’s tumbling around a cockpit….
• Allied to this is the fact that the forces on the camera — and your hands and arms as they hold it — can be tremendous and sudden in a tumbling airplane. I had bruises on my thighs after the first lesson from where my hands holding the camera suddenly hit them as we pulled out of the loop. Learn to brace the camera against your shoulder, a window, the top of the panel, etc., if possible, and learn to predict the aerobatic movements well enough to be able to at least somewhat counteract the resulting movements of the camera. Of course, with a video you can make these camera movements part of the visual drama, as long as you smooth them out (you don’t really have much choice here — even the smallest real Steadicam won’t fit in an aerobatic cockpit, and it wouldn’t be much use even if it could).
• Above all, it’s one thing to fly the maneuvers, it’s another — much harder — thing to video or photograph them from inside the plane doing the aerobatics. The disorientation and discomfort is very real, especially when looking through a viewfinder. You can alleviate the last bit by simply holding and aiming the camera appropriately (everything’s going to be approximately-aimed if you hand-hold the camera in any case, due to the turning and the G forces), bracing it against a window, your chest, your shoulder, etc. But watch out that this doesn’t interfere with the pilot’s yoke or stick travel, as it did during a spin with Ben. No damage, but still…). Frankly, though, how you handle the disorientation is going to be very specific to you, and I’m not sure I can be much help here.

Some useful resources:

• Szurovy & Goulian: Basic Aerobatics, TAB Books, New York, 1994 (ISBN 0-07-062926-9, pbk.). One of many such books, this seems the best. Not the cheapest, but it does a good job of explaining the basic maneuvers and the various why‘s of aerobatics.
• The International Aerobatics Club (IAC) website, “the world’s largest sport aerobatic organization promoting and enhancing the safety and enjoyment of aerobatics” (as they say). Part of the EAA empire out of Oshkosh.
• The local Bay Area chapter of the IAC.
• Cecilia Aragon’s website. Cecilia is a local (Berkeley) aerobatics legend and sometime member of the United States Aerobatic Team.