It is not always easy to evaluate a suitable landing field from a distance of three or four kilometres or even further, but there are a few ways by means of which things can be made easier.

    First of all, before attempting landings in unfamiliar locations, a pilot should practise landing where he or she feels at home, on his own landing field. A good exercise, familiar to all pilots but often underestimated, is that of trying to centre a target point that can be seen during the approach. Another exercise that can be performed on one's home landing-field is landing without using all the available space.

    Of course, the normal safety rules should be followed scrupulously. In these exercises, what we should try to achieve is not flying two metres above the trees on the edge of the field, but rather the security of being able to reach the position that we are aiming for, at the desired height and speed. So there is no need to skim over the neighbouring rooftops, or pick apples from the nearby orchard...

    Once we have gained extensive experience on our home landing field in various aerological conditions, we can start thinking about landing fields that we have never seen before, and the variables that have to be taken into consideration for the choice of a field and the approach.

    I would say that the fundamental factor is the size of the field, determined by the obstacles around and inside the field. Then there is the slope, and, only in third place, wind direction and speed. Another important point to be considered - when this is possible - is the vicinity of other possible landing fields. We will see why later.

    In actual fact, the importance of these factors varies from case to case. Wind direction is not a fundamental point if the wind speed is from 0 to 5 km/h, but it becomes crucial when, due to the limited space available in a given landing field, we need all the help possible in order to "hit the target". For similar reasons, if the wind speed is 35-40 km/h, only a very small patch of ground is necessary for landing, and our descent will be almost vertical. But if the landing field is surrounded by large obstacles, such as houses, industrial buildings, or dense, tall trees, the fact that such obstacles produce turbulence means that the further away they are, the better it will be.

    Another situation consists of landing on a slope. In this case, whatever the strength of the wind, the landing direction is determined purely by the slope. We will look at this subject more thoroughly later on. It is important, and it requires detailed consideration.

    Paraglider pilots may smile on reading how many factors have to be taken into account when landing with a hang-glider. Of course, as the performance of a wing increases, the amount of space necessary for manoeuvre also increases - though the efficiency of a hang-glider can be reduced during the landing approach by means of flaps, spoilers, drogue chutes etc. At the same time, a higher-performance craft gives you more choice, because you can glide further.

    In actual fact, there are very few places in which it is impossible to find a suitable landing field, given sufficient advance warning and enough altitude.

    Let us take a closer look at the factors considered up to here. The size of the landing field can be evaluated from an appreciable distance, and with sufficient experience (acquired by means of the exercises mentioned above), a pilot will soon learn how to estimate the amount of space necessary to make a safe landing

The useful area of a landing field is strongly affected by the obstacles around or on the field. While buildings, trees and ditches are obvious from a long way away, electric cables, telephone cables, cable hoists, wire fencing and vertical irrigation pipes are far harder to see. This is why, if we can choose between a single isolated field and another with alternative fields around it, we should opt for the latter. In that way, if, late in the approach to landing, we notice unexpected obstacles, we can opt for another nearby field - to which we shall have already given at least a quick look.

    Suspended cables are the hardest obstacles to see and the most dangerous, particularly if they are carrying electricity. It is obvious that they should be identified by searching for their respective poles or pylons, because the cable itself is far less visible. Once the pylons have been identified, they will become points of reference during the approach. If the field is so small that we have to make our final approach at a height lower than that of the pylons, we may have to fly alongside the cables. In this case, it is important not to watch the cables, but we should just determine their direction and make sure that we don't get too close. In other words, if we are flying parallel to the cables, we should not be looking to one side, at right-angles to our direction of flight, but much further ahead, as if to compare our direction of flight with the direction of the electrical cables (indicated by the position of two successive pylons). The angle between the direction of flight and the direction of our line of sight should, in my opinion, never be greater than 30°. This is because we tend to direct our wings where we are looking. If our gaze is fixed on an obstacle, we will tend to fly straight towards it.

    The idea of approaching a field by flying under the cables that border it should be considered only if there are no alternatives. In this case, a pilot flying with a kingpostless glider such as the Laminar Zero7 will be at an advantage when compared to a pilot who has a metre or more of king post above him. Not to mention a paraglider pilot who has a wing eight metres above his head.

    In such a situation, our speed during the final approach should not be too high. If, when we are near the cables, we discover an area of uplift, we have to be able to rapidly increase our speed in order to lose height. For the same reason, when we are flying a glider, we have to be ready to release the brakes or, even better, perform symmetrical folds ("big-ears").

    While this sort of approach is definitely inadvisable for a hang-glider, it is even more so for a paraglider. However the paraglider's excellent landing characteristics makes this sort of decision highly improbable.

In the previous article, I was discussing aerial cables. On this subject, cable cars present a different type of problem. The cable in this case is usually between 0 and 50 metres above ground level, but the vertical distance may be even greater. There are no intermediate pylons, excepting those at the top and bottom, which may be a long way apart, and they may be rather small - virtually invisible when in flight. Only rarely do such cables obstruct landing areas, but they can be a serious problem when searching for rising air near mountain slopes. They are hard to identify. If you are planning on flying in an unfamiliar area, it is a good idea to ask local pilots for information, or examine detailed maps (the Compass 1:50000 maps usually mark these cables, but not all of them).

    Now, let us consider a different question: a field large enough for a safe landing, but with some trees or high buildings at the edge of the field that prevent straight finals from outside the field. In this case we have to consider the possibility of turning onto finals inside the perimeter, and therefore inside the obstacles. The wind is a fundamental factor. This type of approach is safe only with a light breeze, or preferably with no wind at all. If, on the other hand, there is a strong wind, you have chosen the wrong field.

    In all the examples that we shall consider, flying speeds depend on the size of the field. The smaller the field, the lesser the speed should be when entering the field, so that one doesn't run out of room while the glider gradually slows down. Of course, speed should never be so low as to compromise the continuous and effective control of the glider.

    In general, one can say that it is more dangerous to arrive too low than too high. In other words, it is less serious to stall onto a tree during the final stages of ground effect at 2-3 metres above the ground than to touch the upper branches of a 10-metre high tree and then plummet to the ground out of control. So, regarding height and speed, we can say that "melius abundare quam deficere" (too much is better than too little)... within limits, of course.

Sangiano: a landing behind the Icaro 2000 factory
    After one of my routine test flights, I prepared to land in the narrow field behind the Icaro 2000 factory. The trees surrounding the field are almost all over 10 metres high, except for the upwind side on which they are 5 metres high. There was a fair breeze. I lost height directly above the factory with a series of 360° turns, and then started a standard circuit, increasing speed briskly on finals and entering the field 2 or 3 metres above the trees. I kept the speed high until I reached ground effect height, where the turbulence caused by the trees at the edge of the field was lower. After landing, I had the usual 150 metres to walk back to the factory.

    I watched Manfred as he began his circuit. He has an incredible control over the glider even at low speeds but, on that occasion, I thought that he was too low for another 360° turn. I expected him to dive, entering a little higher than usual. But he circled once more and then realised his mistake. He had to use all his skill to perform what, I think, must have been the most efficient turn that he had ever made.

    The result: he touched the top 20 cm of the tree - the softest part - with the control bar, and his speed was so slow that he seemed to be flying a hot-air balloon.

    He performed a perfect stand-up landing in the field, just 5 metres beyond the trees. Without doubt, he was able to save the situation by means of his experience, his cool thinking, and a hang-glider providing generous performance at low speeds. Not to mention a healthy dose of good luck. Otherwise this sort of approach can have dire consequences. If you don't really want to walk that 150 metres... well, think again.

    In the first case - virtually no wind at all - the approach should take the form of a modified standard circuit. Once you have lost height on the upwind side of the field and you are not far above the height of the obstacles, turn onto the downwind leg. Increase your speed, dropping to a height below that of the top of the obstacles, and get ready to perform a 180° turn which will bring you onto finals. In other words, the crosswind leg disappears, absorbed into the 180° turn, unless the field is large enough to permit a straight crosswind section. In all phases of the approach, the flying speed should be high enough to permit satisfactory control of the glider, essential when the obstacles are so close, and because there is always the risk of some light turbulence.

    If there is a light, or moderate - though no stronger - breeze, the approach is the same, except that the speed has to be further increased in all stages of the approach in order to achieve a better control of the glider. But you have to be extremely careful. Even a wind of 10 km/h is capable of producing sufficient turbulence to dangerously (considering the small distance separating you from the ground and the obstacles) modify the direction of flight. When making the 180° turn that brings you onto finals, remember the drift caused by the tailwind that will have the effect of widening the turn. Therefore you should start turning earlier than when there is no wind. This is unnecessary in an open field or a field with just a few obstacles, but it is fundamental in the case under consideration here.

We were talking about landings in a field surrounded by high obstacles. Let's look at another example in this sort of situation. If the wind is from moderate to strong, as I said before, you've chosen the wrong field. However, if you have no choice and you have to land there even in a strong wind, it may be better to use the figure-of-eights approach. Because of the wind, you won't fly real eights, but you will move crab-wise back and forth along the downwind side of the field until you are just a few metres from the top of the trees or buildings.

    If you choose the standard C-type circuit, you have to be prepared for changes in windspeed and therefore changes in your height. This means that it may be necessary to make extra turns in order to use up excess height, or shorten the downwind or crosswind legs if you find yourself in a current of descending air. In these conditions it is very important to stay close to the perimeter of the field. Whatever the circuit you have chosen - figure-of-eights or standard - once you are over the final obstacle, increase your speed to just below top speed (not the fastest possible, because lateral control is not perfect when the bar is close to your knees) and line up for finals. It is important to increase your speed just before you reach the area in which the effects of wind gradient are marked. This usually starts from about ten metres above the top of the obstacles. If you let the relative windspeed drop off, because of the wind gradient, you may not be able to maintain correct control of the glider.

    Landing in these conditions is very difficult, because of the powerful turbulence and the steep wind gradient. You have to remember, above all, to keep the wings level and the direction correct. Keep speed high until the moment that you level out just above the ground, and then continue in ground-effect until the kinetic energy acquired has been depleted. It is fundamental to maintain sufficient speed until you are very close to the ground, where the wind gradient disappears and turbulence is greatly reduced. The stronger the wind gradient and turbulence - in other words, the stronger the wind and the higher and closer the obstacles - the lower you will start reducing speed. And if you manage to perform a stand-up landing - I take my hat off to you!

Pre-European Competition 2003, Millau, France
    This task was for a flight of about 100 km. It began with a few kilometres in dynamic uplift, on the cliffs dropping from the plateau into the bowl of Millau. Then a 50 km section, almost all with a tailwind, over another of these enormous plateaus. The rapid transition from a sky punctuated with cumulus clouds to the blue thermals of the plateau caused problems for everybody. After having regained height from fairly low altitudes twice, when I was still twenty kilometres from the finishing line, I began to prepare for the final glide down. Of course, I didn't want to let those who had started after me catch up with me, and so I let my confidence run away with me. Stupidly, I didn't exploit the 3 m/sec thermals.

    The distance to the goal required a glide ratio of over 17, and my Laminar 4.2 could have enabled me to arrive... if it hadn't been for a hill that blocked my path three kilometres from the finishing line.

    There was a small clearing below, surrounded by bushes and trees, some at least 5 metres high. I had little more than the bare minimum of height necessary to reach the downwind side of the clearing, while I ruefully thought of the 3-metre thermals that I had ignored, and the better landing fields that I had left behind a few kilometres earlier. But this clearing was now the only chance at landing I had left.

    I slowed down... my speed over the ground was very slow. Even slower. For a few intense seconds, I remained suspended in the air. I imagine that a falcon must have the same sensation when, just before diving onto his prey, he hovers and observes it. His life depends on the success of his attack. I tried to anticipate the gusts of wind, and when I would begin to feel the wind gradient. I trusted in the glider...

    And thanks to the glider's wings, for a brief moment the sensation of "feeling", almost anticipating, the wind pattern gave me one of the most incredible experiences that I have ever had flying. I really felt that those wings were my wings ...

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