You might think circuit training is something you'd do in a gym, but circuits in an aircraft are almost as much work. I had an initial go of circuits about six months ago, on a day when the cloud was too low for anything else. Back then, I hadn't learned any of the manoeuvres, so it was very hard work and the circuits were far from neat. This time, I knew how to fly all the manoeuvres independently, but my instructor warned me it would be quite different. When you learn to climb, descend, and turn, it's all with reference to the moving air: you turn onto a particular compass heading, and fly everything by airspeed. In the circuit, everything is in relation to the runway on the ground. It's no use flying with your nose lined up with the runway if the wind is blowing you sideways. And because the wind can be different between the ground and 1000 ft (circuit height), you can't plan how much you need to correct for it: you have to keep one eye on the runway and keep making adjustments to your heading to stay on track.
A quick terminology note: heading is the direction the aircraft is pointing; track is the path it traces out over the ground. So if the wind comes from the east (090°), and your heading is direct north (360°), your track will be somewhere north-west (say 340°), depending on how strong the wind is. Through the air, you're going the direction the aircraft is pointing, but the air is moving right-to-left over the ground and carrying you with it.For the first circuit, my instructor demonstrates everything, describing his actions as we go. As soon as he lands, he gives control to me, and I begin the take-off roll for the second circuit. In the briefing we'd agreed that I would be in control up to the final approach, and he would complete the landing; also that he would run the radio this time so I could concentrate on the flying.
Starting from the white star on the diagram (and going clockwise), I open the throttle and we accelerate along the runway. It's a lot easier to keep it straight now I've done it a few times. Even so, as the tail starts to lift, I feel as if we're going to tip up and hit the propeller on the ground, so I keep holding the stick back. This makes the take-off run longer than it needs to be, but soon enough we're airborne and climbing out. There's a tiny bit of cross-wind, so I have to steer a little to the right to stay in line with the runway as we cross Newmarket Road.
|The offending throttle lever, including the friction nut which holds it in place.|
The track for the elevator trimmer is just visible at the bottom.
As we've already passed the aerodrome boundary, once we get to 500 ft it's time to make the first right turn. It's a climbing turn, so I'm careful not to bank too steeply. I have to watch over my right shoulder to judge the angle: I should be at right angles to the runway direction, but of course the runway is already somewhat behind me, so it's a little tricky to judge. Luckily, this isn't the part of the circuit that has to be precise.
I need to make the next turn when the runway end is at my four o'clock, but as predicted in the briefing, by the time I reach 1000 ft, level off, and trim, it's already time to make the turn. In fact, on this occasion I'm a little over 1000 ft, because I didn't start levelling off early enough.
This turn is just a standard-rate, level turn, so not very exciting. I still have to keep one eye on the runway, which is now at my one o'clock, so I can make sure my new track is parallel to it. By now I can hardly see the grass runway: after all, it's just a strip, no wider than a dual-carriageway road, of slightly shorter grass in a field. The huge black rectangle of the main runway is a much more obvious and a better guide.
When we're in line with the upwind end of the runway (blue diamond), it's time to make the "downwind" call on the radio, and my instructor does so as we agreed. After that, it's time for the approach checks, which don't take long, but serve to fill up the time as we fly alongside the runway.
Soon enough, it's time to make the third turn, another level one onto base leg. This is where I start to get nervous. Shortly after rolling out from the turn (green diamond), my instructor tells me to close the throttle. I hold the nose up until our speed decreases to 65 mph, and then let the nose drop so the horizon is nearly up to the bottom of the fuel tank. We're in the gliding attitude, and that should carry us all the way to the runway.
Next it's time to begin the turn onto final approach. I have to bring us in line with the runway, while also keeping the descent stable. Because we're gliding, the turn has to be quite shallow, so I was warned in the briefing to start early. It's easier to make the turn shallower if I turned too early, than to try to correct an overshoot. From my previous experience of performing this early part of the approach, I know the formation of trees to line up on. During the turn, I mainly look down at the runway, because I can see it over the side, but by the time I roll out, I have to judge based on the skyline in front of me.
I continue to descend as the instructor gets clearance for a touch-and-go landing. I feel like the aircraft doesn't want to descend: the airspeed keeps creeping down below 60 mph. I try to put the nose down, until the horizon is brushing the underside of the fuel tank. It's clear that we're actually a little short of the runway: we're going to touch down on the disused runway 28 (zoom into the map). My instructor tells me not to worry about that this time, just keep a stable approach.
I'm hanging all the way over the left side with the wind in my face, one eye on the horizon ahead, one eye on the ground below, and one on the airspeed indicator. Already we're lower than I've ever flown, and any second I expect the instructor to take control, but he doesn't. Suddenly he says, "Flare now! Pull up!" and I realise he is going to let me take it all the way down. Slowly I pull the nose up, but the controls are very ineffective at this low speed, so we're still sinking and only a few feet above the ground. We're still way too fast, and I'm still trying to get into the three-point attitude when I feel a bump from below, and we have bounced.
"I have control," he says, and even without waiting for me to read back, he pushes the throttle all the way forward so that we're flying level along the runway. I was only expecting to practise approaches, so I'm a little shaken by the excitement of flying the Tiger Moth all the way to the ground. There's no time to reflect on that achievement, as we're ready to climb out again for another circuit.
The other circuits are all pretty similar to the first. We have good, stable approaches each time, but we never manage to land anywhere near the runway numbers. The only one that was at all close was when I thought we were so high we'd fly right over the runway without touching down.
I'm pretty hyped when we get to the debriefing afterwards. The thing I had to ask about was that the aircraft felt as if it had a mind of its own today. Every time I rolled out from my turn onto base leg, we ended up very nose-high and I had to pull the stick back quite far to keep a level attitude. The instructor wasn't sure why that might be: probably thermal currents or windshear in that area. It's just something I have to be ready for. I think I did quite well at being ready for it: even the first time, I corrected the unwanted change in attitude, and on later circuits when I knew to expect it, I was able to anticipate it to prevent the nose-up in the first place.
The instructor had a question for me, too. He asked why I kept pitching down when we were about 100 ft from landing. I answered (as above) that the airspeed was dropping and I was trying to keep it up. "I knew that would be it!" he exclaimed. Once you're established on final approach, you should stop looking at the airspeed indicator, he told me. Just keep the right gliding attitude down to the runway, and if the speed naturally falls a little, don't try to chase it. Trying to keep that airspeed up at low level is why we always reached the runway too fast and bounced.