Copyright 2003 Hamish Reid
Aerobatics and Unusual Attitude Training
Now Do A Loop…
“Now do a loop”, he says. Six thousand feet above the golf course, I push the Aerobat into a shallow dive to about 130 KIAS, then pull back sharply on the yoke, pushing me down into the seat with about a 2G force. Pitching past level I keep full back pressure on the yoke, firewall the throttle, and ensure that the ailerons are still neutral. I look out to my left and watch the horizon turn. When it gets to a little past vertical I slowly ease off on the elevator. Then I look “up”… as the ground comes into view through the skylight windows at the top of the cockpit, and the slightly reduced G’s make me feel like I’m floating for a second or so. I follow the ground into the main windshield and note the power lines thousands of feet “above” (i.e. below) me — we’re still on heading, more or less. When we’re nearly at the 240 degrees point, I start pulling back on the elevator again and pull the throttle back to about 1,700 RPM. I keep the rudder fairly neutral, and pull back harder on the yoke as I watch the heading in relation to the power lines. We pull about 3 or 4 G’s as we level out on the original heading, having lost perhaps a few dozen feet vertically. In the right seat Ben Freelove, my aerobatics instructor, laconically notes that I could have pulled up even more sharply in the initial stages, but I’m feeling pleased: we made it around the loop without killing anyone or losing much altitude, and that’s good enough for me at this stage. This could get addictive….
Why aerobatics? (And why me, for that matter? — I’ve certainly never thought of myself as an aerobatics kind of guy). When I originally learned to fly, I rarely considered going on to do aerobatics. It wasn’t that I was particularly uninterested, just that it seemed like a long shot for me, a basically klutzy semi-intellectual nerd who always thinks of himself as unathletic and way too fragile for that sort of thing. One day while I was still getting my PP-ASEL Lou Fields offered to teach me some real flying in his Pitts, but I was sure I’d get airsick, and I learned to fly his Arrow instead for my complex endorsement. On the other hand, I’ve always believed that mild aerobatics and the associated unusual attitude handling and recovery techniques are useful things to know for any pilot, and I’d certainly thought about doing a short course with another club or organization some time.
So when I heard that Ben would be offering unusual attitude and / or basic aerobatics training for club members in the club’s little Cessna Aerobat (N7336B), I got curious. Curious about what it takes, curious about whether I could do it (aerobatics as well as the recovery stuff), and curious about the process of instructing aerobatics itself.
Also, my Grandfather was intimately familiar with aerobatics, having flown in WW1 for the British RFC, and in WW2 as a fighter instructor with the RAF, so I grew up hearing a lot about the various maneuvers and dogfight experiences, and as a child I think I (and much of the rest of my family) somehow assumed that I’d be rolling and looping one day too. So here I was.
Lastly, looking back, I have to admit I’ve really never been seriously airsick, seasick, or carsick, so I’ll have to stop using that as an excuse sometime… this seemed like as good a time as any.
So I talked to Ben and signed up for some very basic aerobatics training. My expectations were pretty low — I really wasn’t sure this would work, or that I’d be up to it, but I was willing to try. In return for helping him with his new website — a bunch of photos and / or videos of the experience, plus the usual HTML (etc.) work — he’d give me a few lessons. Seemed like a good deal to me….
The plan for today is to gently introduce me to the absolute basics: spins, aileron rolls, and loops, to let me decide whether or not this is for me; and if we have the time, to get some photos that might be useful for the website.
We start in the clubhouse after I’ve preflighted 36B. Ben sits me down in front of the whiteboard and we discuss basic spins, the various types of rolls, and basic loops, with a strong emphasis on how to recover if things go wrong. Today’s lesson concentrates on basic spin recovery (two methods), aileron rolls (one of four species of roll Ben diagrammed for me, the others being barrel rolls, snap rolls, and slow rolls), and basic loops. It isn’t clear to me how much of this will really sink in, let alone how much we’ll actually get done the first lesson, but it all makes sense. Intellectually, that is; it just isn’t clear to me how much physical sense it’s going to make up there over the practice area. And it certainly isn’t clear whether I’ll survive without becoming sick or disoriented.
We run very carefully through the use of the parachutes and emergency exits. In 36B you can get rid of the doors completely by pulling the red “D” handles above the front hinges; this helps a lot, as otherwise it’d be even more of a struggle than usual to get out while the plane’s uncontrolled or spinning. The parachutes themselves are smaller than I’d expected, much lighter, and fit me well, but they also need close preflight inspection to ensure the rip cord and harnesses still work. Ben is pretty specific about the situations in which we’ll bail out: structural failure; inability to pull out of a maneuver below 3,000′ AGL (the “floor”), and any time he judges that things are unrecoverable. I can’t pretend I know what’ll happen if I have to bail out, but it’s at least an option, unlike in normal flying.
So we take the chutes out to the plane, and — something new to me, but obvious in retrospect — we carefully find and remove every bit of loose or potentially loose gear in the plane, including checklists, charts, rags, and stray bits of paper. Having a runaway sump drainer hit you in the face during a loop, or getting some unidentified bit of loose carpet stuck behind the pedals in the middle of a roll, could be distracting at best, disastrous at worst.
This also plays into what I’m going to do with my camera, a Nikon D100 digital SLR I use for things like this, where the results are mostly destined for the web. I’d thought about this the previous evening, and I’ve brought along a largeish cross-country skiing fanny pack (“bumbag” for UnAmericans like me) into which the camera and associated lenses and filters can be safely stowed. I wear this pack across my chest, which works a charm, but the combination of pack and parachute makes me feel like an overstuffed bumblebee on the ground. The pack also has two pockets for small water bottles, which later turn out to be the most important feature of the whole setup.
We depart Oakland and head out past Mt Diablo, climbing steadily to 6,000′. Ben defines the practice area for me, and we make several clearing turns keeping a damn good lookout for other planes in the area (and we’ll end up doing this many times every lesson, of course). Under the practice area there’s a large golf course and country club, and a set of jagged hills leading up to the main slopes of Mt Diablo. The practice area has a bunch of things like power lines and minor roads on the ground that can be used as heading marks or spin counters, and more distant landmarks like Mt Diablo or Mt St Helena are also useful.
The first thing we try is a developed left spin. I want Ben to show me how it’s done, while I’ll take photos of the ground spinning through the front windshield. Big mistake. The spin goes just fine — but I’m totally unprepared for the various forces from the spinning and the dramatic nose-down attitude, and I couldn’t even hold the camera up steadily, let alone take useful photos. It’s hard to describe just how disorienting a real developed spin can be when you’re not used to it — it’s obvious how pilots spin in without regaining control, or even just freeze when it happens.
Anyway, after a couple of turns in the spin, I feel quite disoriented. Not so much sick, just confused. So I ask Ben to do it again (OK, so I failed the obvious intelligence test here). This time I’m prepared for the spin forces, and I shoot a few photos. Even bigger mistake — by the time we recover from the spin, with me focusing through the camera, I feel really disoriented. Still not sick, but if I keep doing this I will be. This is going to be much harder than I expected.
But I’m determined to learn this, so we do it again. This time, though — and maybe the spins are starting to knock some sense into me — I put the camera back into its pack and just concentrate. And sure enough, it’s a lot easier when you’re not looking through a viewfinder. I throttle back, pitch up slowly, ride it into the stall, then kick in full left rudder just before the nose falls. The effect is dramatic — the kick into the spin is unmistakable — and suddenly we’re pointing what seems like straight down at the ground with the windshield entirely filled with golf course and roads spinning quickly clockwise. I don’t lose my head, and after what seems like an eternity, I ensure the throttle’s at idle and the ailerons neutral, then kick in opposite (right) rudder. The spinning stops almost immediately, and I push down on the yoke “briskly” (as both Ben and the POH advised). We pick up airspeed and end up flying straight again, perhaps 1,000′ feet below where we started. I did it… I think “that’s the ticket!” and feel immensely better than just a few seconds ago.
We do a bunch more of these (all left spins), with me steadily getting used to it, and being able to do more turns (really, the first few probably went only a single turn, if that. It’s actually very difficult when you’re a beginner to keep count, and it sure felt like we’d done dozens…). Recovery seems “natural” in this plane, using either the Cessna-recommended PARE technique or the Beggs-Mueller “just let go…” emergency technique I learned earlier with Dave Montoya; Ben had briefed me well on both. I forget about the camera, but can’t help thinking every time the ground fills the windshield just how cool this will look on video…. And I’m starting to feel comfortable!
One of the spins results in a spiral dive when I don’t maintain full rudder pressure through the incipient phase properly. It’s remarkable how easy it was to tell just by feel that we weren’t in a real spin — the angle’s different, the airspeed higher, etc., but basically it just didn’t feel like a developed spin at all. Plus (and this is a basic thing you pick up in aerobatics) it sounds different. When the Aerobat goes beyond the incipient phase, there’s a quite noticeable kick as the autorotation takes over and stall continues, but the spiral dive just felt more like, well, a fast smoothly-developing spiralling dive, with a rapidly increasing wind noise on struts and surfaces. Dramatic, but quite different to a spin — and you have to recover from a spiral dive as soon as you recognize what’s happening, so that you don’t exceed Vne and break the wings; whereas you can keep the spin going for almost as long as you have sufficient altitude because the actual airspeed in the spin is by definition quite slow.
It’s also remarkable just how much effort it took to get the Aerobat to spin properly. Yes, it’s a trainer, and designed to recover itself and not spin unless you really push it, but I was expecting it to spin with just a bit of yaw in the stall. A lesson that will recur today and the next few sessions is that you can’t do aerobatics with the traditional gentle two-fingers-on-the-yoke approach many of use when flying the 172’s or the Arrow. You have to use full deflection, and keep things fully-deflected, for a large part of each maneuver. This goes against all my instincts, and it shows in the next lesson: aileron rolls.
Aileron rolls are the easiest of the rolls, and involve little excess G’s and no negative G’s. Ben shows me how they’re done: a shallow dive to about 120 KIAS, pitch up to about 30 degrees with full throttle, roll the ailerons fully in the direction of the roll, neutralize the elevator, and use the rudder “appropriately” (I have a bit of trouble with this part now and in the next few lessons — it’s not always obvious which way to push when you’re upside down). When you’re rolling back towards the horizontal, pull back on the elevator and throttle, and recover. Just like that… and just remember to keep those ailerons fully deflected.
The first time through I just love it. As we come out of the roll I can’t help saying “That’s so cool!”. Let me try this… and so I do, for perhaps half a dozen left aileron rolls. All of them a bit rough, but none of them horribly wrong or anything, and suddenly I start to think: this isn’t so bad. I can do this! It’s hard to describe how enjoyable and satisfying it is when you get something like this right, and the world revolves around you slowly and gracefully.
But then we try loops. Ben talks me through the first, while showing me how it’s done. At the point at which you have to look left to watch the horizon, I realize I still feel a bit wrong; by the time I look “up” and then feel the 4 G pullout a second or two later, I’m feeling disoriented again. Still not sick, but badly in need of level flight for a while. I feel really heavy, and suddenly rather tired. I know we’ll have to stop the aerobatics now, so I tell Ben we should head back while I take a few photos on the straight and level.
By the time we land, I’m feeling a bit better, but still not particularly well. It doesn’t feel like motion sickness or disorientation any more, and I’m puzzled. We debrief, and Ben’s generally pretty pleased; we book another lesson in a few days time. Walking back out to the parking lot I realize what much of the problem is: I’m badly dehydrated, and quite sunburnt. After a few drinks of water and sitting around for a while, I feel a lot better. Another obvious lesson relearned…
Some lessons learned from today’s session:
- Watch out for sunburn and dehydration! Both can creep up on you very quickly in the Northern California sun, especially six or seven thousand feet above the ground. Next time I’ll wear a hat, apply a lot of suntan lotion, and use both water holders in my camera pack.
- Positional and attitude awareness is crucial in all these maneuvers, but very difficult for a beginner, especially during spins, when I really couldn’t have told you how many turns we were making. Ben says I’ll get a feel for this very quickly, but it all seemed a blur to me….
- You have to work at the damn controls! No more two-finger flying, or gently pulling back on the yoke — this is more like a real workout, and you have to hit the stops all the time, but smoothly. No subtlety here. This is hard for a low-time GA pilot like me.
- Aerobatics is all about seat-of-the-pants flying. The gyro instruments are useless, and you quickly learn to judge things like airspeed and attitude by feel and sound. I haven’t got it yet, but like attitude awareness, Ben says it’ll come quickly enough.
- Above all — don’t even consider taking photos or videos until you’re used to aerobatics. Nothing makes you more disoriented than shooting through the viewfinder of a camera while spinning or rolling wildly…. I vowed that the next lesson would involve no photos at all, just the basics.
Later, walking down the street near my studio in lovely Industrial East Oakland, I think: hey! I can do this! I just rolled and spun an airplane and survived just fine! I feel great. And that’s the main lesson here for me today. But I’m still worried about my reaction to the loops, and the overall disorientation while taking photos. We shall see…
What Does It Take?
So what does it take to legally fly basic aerobatics in the US? Remarkably little, really. Surprisingly, the FAA doesn’t have any aerobatics-specific certificates or ratings — you just have to be rated for the plane you’re doing it in (e.g. complex and / or high performance and / or tailwheel endorsements). As with most US flying these days, it’s the insurance company that really sets the standards — and here you can expect to have many dozens of hours dual aerobatics training before being insurable at all, let alone cheaply. As for the club itself — well, the little 152 Aerobat I’m flying (Cessna 7336B) is owned by our Chief Pilot Dave Penney, and it’s up to him and our insurers to make that decision…
Also, the FAA says you must carry parachutes when doing intentional aerobatics. This is pretty sensible, and certainly makes it easier to believe you can survive the whole process. Actually having training in using them isn’t needed, but any competent instructor will cover the basics, as Ben did on my first lesson. Parachutes cost a lot, can weigh a lot, can be bulky, and must be re-rigged every 120 days, so this is not a trivial part of the equation.
Where can you actually do aerobatics? The FAA says some fairly obvious and sensible things here: don’t do it within 4 nm of airways, or over congested (built-up) areas, or close to the ground. In the Bay Area there are way too many airways and built up areas to be able to do aerobatics in most places; and the situation is only getting worse, with endless new developments stretching across the Delta, the Diablo Valley, and the various hills and valleys towards Sacramento, Tracy, and Stockton. So legal aerobatics practice areas are few and far between; we do our work the other side of Mt Diablo over the hills and golf courses out towards Brentwood and Oakley. Like the rest of the Bay Area, this is an area increasingly affected by the relentless suburban sprawl (much more extensive now than when I first saw it in 1999); my guess is that within three years it’ll be illegal to do aerobatics there as well. There are also designated aerobatics boxes for real aerobatics near Tracy and New Jerusalem. In any case, there’s quite a bit of flying between Oakland and wherever you want to practice…
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.
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.
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….
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.
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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.
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.
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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.
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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.
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