The Aviator's stage

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Making a good entrance and exit is vital for a competition aerobatic pilot. Just as it is for an actor. Polish those thespian skills.

‘ALL the world’s a stage,” according to Shakespeare in As You Like It. Naturally, this is also true about flying an aerobatic sequence, whether for display or competition.

The Bard goes on to say, “And all the men and women merely players. They have their exits and their entrances.”
I’ve always thought it a shame he put ‘exits’ before ‘entrances’, as that surely is the wrong order of events. Such laxity, afforded by poetic licence, is not available to the aerobatic artisan. We have to start before we can fi nish, and pay particular attention to what goes between.

AN ENTRANCE
My preparation for a sequence always employs a plan that starts the moment my wheels come off the ground and continues until I am back on terra fi rma. Just as an actor needs to know everything he is going to say and do from the moment he leaves the dressing room until he charges off to the bar after the final curtain.

The first phase is organised around three vital needs: First, to put to rest any lingering doubts about the strength of the wind both along and across the main axis of the ‘box’.
Second, to check and exercise the aircraft systems needed for inverted flight (fuel system, oil system, pilot restraint).
Third, to make sure I start Figure 1 in exactly the right place.

Starting in the right place is arguably the most important aspect of the sequence, and can only be achieved with a sound plan. This has to be updated in real time by an understanding of the actual wind velocity at 2000-3000ft above the ground and by a reinspection of local ground features associated with the box and the judging position/crowd line.

I will illustrate all these points by describing the start of the last competition sequence I flew. This was at Compton Abbas, whose runway is orientated 08/26 with the crowd watching from the centre of the strip and only 50 metres or so to the south of the runway edge. The audience thus looks north, with the sun (ha!) behind them.

WIND CHECK
The surface wind was varying a bit, as various rainfilled cloud formations streamed past, but was generally down the strip from the west. The upper wind was also likely to swing about as there were large CB clouds in the vicinity. It was an Advanced Free Programme, with all pilots fl ying their own, different sequences, so I could not rely on watching other competitors to get an idea of the wind aloft. My plan therefore included an airborne windcheck, to discover whether the 2000ft wind had a component blowing towards or away from the judging line.

A short left-hand circuit after take-off (the Extra 300 climbs at around 3000 feet a minute) saw me at 2000ft, at a speed of 90kt, to fl y the whole length of the runway, heading along it into wind, to judge any drift. Flying a perfectly constant heading, in balance, is essential for this, so even straight and level has to be mastered to be a good aerobatic pilot. The Extra is happily well endowed with clear vision panels in the fl oor of the cockpit, so that drift across the runway can be gauged readily by eye. It was slightly on-judge, but not very much.


INVERTED CHECKS
My Free Programme this year, designed primarily for the European Advanced Championship in Finland last July, has fi ve ‘pushes’ when I have to go from vertical to horizontal (or vice versa) at -5 or -6g. The inverted fuel/oil systems have to be working and my harness has to be both tight and comfortable.

The Advanced Rules allow me to perform two level half-rolls, stopping inverted to check things, and a single warm-up figure, before starting the sequence proper. As my sequence starts at very high speed directly towards the judges, I choose a vertical warmup figure which lets me rehearse the initial dive. At 200 knots with a slight tailwind, I must be very precise about where I start and finish my diving line so as to pull up for Figure 1 in the right place.

After the wind check, then, I keep climbing and turning left to position myself into wind, parallel to the runway and about a kilometre or so north of the centreline. Here, at 90kt into the 20kt westerly, my ground speed is relatively low and I can spend time locating some farm buildings ahead as well as monitoring the judging position to my left.

At what seems the right place, I make a 90-degree left turn to point straight at the judges and almost immediately start a 45-degree dive, looking for 200kt.

While descending, I note how much the wind drifts me to the left and make a note to go further into wind next time. It also becomes apparent that I am getting closer to the runway than I want to be for Figure 1 when I start in earnest. Noting this as well, I pull up into a pull-pull-pull humpty-bump. On the way down I confirm the drift from the main-axis wind, and also that I am too close. Coming level at just under manoeuvre speed, I roll sharply to inverted, push sharply a couple of times to pull out any wrinkles in the harness and then check the oil pressure is where it should be. It is, and the engine is not fuel starved.

That’s OK then.
I roll upright and into the left climbing pattern again, getting a couple more ‘clicks’ on my Hooker ratchet harness and pinning my hips to the seat.

RUNNING IN
Now I’m back ‘on the perch’: 2700ft, 90kt, into wind, parallel to the runway. This time, however, I’m an additional 300 metres to the north. This will make the necessary allowance for the tailwind when I dive again. I fly a bit farther this time before turning south. 200 metres past the centre-spot before heading toward the judges. For real this time.

I stop the 90-degree left with the nose still a little to the right, holding a bit against the main axis wind. I do a single wing-dip, 45 degrees of bank, left wing down. No heading change. Look at the judges. Now the dive again. 45 down, two more wing-dips while accelerating. I slip the nose left at the end of the last dip, putting me exactly at right angles to the runway. A quick, controlled pull to level at 200kt then almost immediately vertical into Figure 1.

Out of Figure 1, I’m inverted, low speed, into wind for a spin. Looking up over my right shoulder I see I’m parallel to the runway and pretty well the right distance from it. The plan has worked so far...

MOVEMENT
I’ve now made my ‘entrance’ in the right place. For the next 4 or 5 minutes I move around the stage. Left and right as they see it, front and back too. I leave a little more time between some figures, heading into the strong(ish) westerly. Going east, I work quickly out of one figure into the next, before the wind has a chance to push me too far stage left (the audience’s right side – remember drama classes at school?).

At the end of Figure 4, I fl y straight towards the judging position but for only a very short time. Figure 5 finishes back into wind on the main axis, but I still need to be 500 metres or so away from the judges. Any closer and they’ll find it hard to judge the next two looping shapes.

During Figures 10 and 11, I watch closely to see how the wind affects my track. The last Figure, 12, is a quarter rolling turn which I really want to do so that it finishes towards the judges. Will I have enough room to finish it with a slight tailwind and still signal the end of the sequence before I cross the runway?

At the end of Figure 11 it looks marginal to go ‘towards’, so I choose the safe option of going ‘away’. I sacrifice the easy visual cue of the runway to avoid the risk of a low Framing score by finishing too close. Nothing is ever perfect. I have to trade off one imperfection against another.

EXIT STAGE
I finish my performance with three wing dips tracking directly away from the judges. No applause for me. No encore. And I’m in no rush to land. The cylinder heads must cool a bit, only slowly, and I must change my aerobatic head for my landing one.

SUMMARY
Planning is a pre-requisite. No one gets to perform Shakespeare unless they learn the words and attend rehearsals. Evaluation of the plan in real time is a necessity. Back-ups have to be in place. Ad-libbing is not an option. We all have a bit of the Olivier or Gielgud somewhere inside us. Travolta, even, if you’re younger.
Be safe and enjoy your flying.

THE SEQUENCE –
PRACTICE MAKES PERFECT
1. Vertical up, three quarters of a 4-point roll.
2. 11/2-turn Inverted spin, half roll opposite.
3. Stall turn, quarter roll up, two-eights roll down and push to level.
4. Push up stall turn, 3/4 positive flick down, exit cross-box.
5. Stall turn, two-eights roll going up, two quarters down.
6. Half loop up, two half rolls left, half negative flick with left foot.
7. 11/2 rolls, half loop down, four half rolls.
8. Humpty-bump, half roll up, pull, 3/4 roll down.
9. Humpty-bump, two quarter rolls up, pull, quarter down and push level.
10. Stall turn, push up, push out.
11. Three half rolls, half loop up, one full roll.
12. 90° turn with one roll to the inside (rolling turn).

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