Circuit, approach and landing

Now it’s time to make our way back. We are to the north east of the airfield, after all our manoeuvrings, and at present flying west. Away to our left we can see the trunk road that passes just north of the airfield. We will steer to inter­cept it and cruise back to the airfield, keeping just to the right of the road (the rule is keep to the right when following such a feature). We will also gently descend to 2000 ft.

Before we get too close to the airfield, let’s plan carefully what we are going to do, while we have time to think and there is no other traffic to avoid. When

Fig 10.1 Joining the circuit for a landing

we get close to the airfield we will be very busy! Runway 22R is in use, so we will need to overfly the circuit (Fig. 10.1), before joining it for a landing. The circuit height is 1000 ft above the runway, so we will overfly the northern end of the runway, crossing above the runway numbers 500 ft higher than the circuit height. Remember, our altimeter is set to QNH (measuring altitude above sea level) so we will need to add the elevation of the airfield to give a reading of 1700 ft. This means we will cross the end of the runway well out of the way of any aircraft landing or taking off and, after this, we will turn par­allel to the runway, on the opposite side to the circuit (the ‘dead side’) and descend to circuit height. Then, we can re-cross the runway, at the other end and, if the circuit is clear, join it. Sounds complicated but this procedure will keep us clear of other aircraft in a relatively crowded airspace. With any luck Fig. 10.1 will make things a bit clearer. Now we have sorted things out in our minds and the airfield is just a few miles away; we give them a call to say that we are intending to rejoin the circuit.

Now to put into practice all that we have just planned. First we throttle back slightly, get our altitude down to 1700 ft and aim to cross the runway at right angles at its northern end. We cross at 1700 ft and soon it is time to turn left so that we are flying parallel to the runway on the ‘dead side’ (Fig. 10.1). As we reach the circuit height of 1200 ft, we level off by applying slightly more throttle and then turn to cross the other end of the runway. Another left turn finally brings us into the circuit and we call ‘downwind’ to let everybody know where we are and run through the landing checklist to make sure everything is prepared.

Now things start to get really busy! We are well past the end of the runway so we make another left turn on to ‘base leg’ and immediately throttle back to 1500 rpm, put carburettor heat on (we don’t want the engine to quit on us now!) and, at the same time, pull back on the yoke so we lose speed but keep altitude. As the airspeed falls, we see that we are just entering the ‘white zone’ on the airspeed indicator, which means it is now safe to lower the flaps. The flaps are extended by two stages on the base leg. As they extend there is a marked change in the trim and it becomes necessary to push forward in order to keep the nose down. When the flaps are extended, the speed is still reducing and, as it approaches 70 knots, we adjust the forward pressure on the yoke to keep it at this value. Now we are in a steady descent at 70 knots and we can trim the aircraft so that it will fly in this condition by itself.

While this is happening we need to keep a close check on our height and where the airfield is. Eventually we turn towards the runway for our final approach and landing. As we do so we lower the final stage of flap. This time there is very little trim change but because of the extra drag, the speed falls to 65 knots. We call ‘final’ to inform other traffic and the airfield and concentrate on aiming at the numbers at the beginning of the runway but keeping strictly to 65 knots. If our speed drops we must push forward and, if the rate of descent seems too high, we apply a bit more throttle. When we increase the throttle, note how we have to adjust to keep the nose pointing in the right direction. Because of the offset thrust line, an increase in throttle setting tends to pitch the nose up and also roll the aircraft because of the extra torque.

As we approach, we find a tendency to drift off to the left. Remember that crosswind when we took off? We must compensate by rolling slightly right and keeping the nose pointing down the runway by putting in a bit of opposite rudder to induce a slight sideslip. Now we are nicely on the approach but we must be alert to correct for anything which might disturb the aircraft, such as the wind over the group of trees, which causes us to sink too rapidly as we pass overhead.

At last we arrive at the runway threshold, a few feet above the ground. Now we can stop worrying about the speed. We set the throttle to idle and pull back into the ‘flare’ until we are flying just above the runway. We now need to change where we are looking so that we can judge height and pull back as the speed falls off to keep flying parallel to the runway. Slightly too much pull back and we find ourselves a bit too high. So we freeze on the yoke (if we push forward we shall probably overcorrect!) until we sink to the proper height again. Eventually the stall warning goes off, the yoke is right back and we sink gracefully on to the main wheels. As the nose wheel touches, we gently apply brakes and, when the speed is low enough, pull off the runway to the left to get out of the way of any following aircraft. Next we come to a halt and clean the aircraft up – flaps up, carburettor heat to cold, lights off apart from the anti-collision beacon, radios off apart from the communications (we will want to know what is happening until we have actually parked the aircraft).

When this is done we open the throttle and taxi back to our parking space. Finally, we let the engine run at 1200 rpm for half a minute, so it’s not too cold after all that idling, check that both magnetos are still working, put the throttle to idle and pull out the mixture to lean. This finally stops the engine and we turn off the master switch and remove the keys and all our belongings from the aircraft to finally complete our flight.

Now we have got down in one piece, you might like to try the numerical questions in Appendix 3. They are all connected with our flight but you will need to look at the other chapters before you will be able to tackle them.