Serious Hazards
Now that I have told you how safely this can be done, I'll highlight the hazards. Thought I would cover this while I have your attention.
The most dangerous hazards associated with off-airport landings are:
• WIRES
• SLOPES
• FENCES
Learn to cope with slopes, avoid wires and fences, and chances of ever causing serious damage to the glider or yourself are minimal.
WIRES
Wires are by far the greatest hazard, and the most often cause of serious field landing accidents. Every so often, there will be wires on the approach which cannot be seen in time to avoid them - wires, the invisible menace.
When we look at wires from the ground they appear quite visible. So, what are we talking about, "The invisible menace?" The problem is that when we are in the process of landing we are not viewing wires with the sky in the background, but against trees, earth, crop, etc. which tends to camouflage wires very nicely, and when the angle of light is unfavorable they do indeed become invisible. To assure we never make an unpleasant discovery, we must pretend there are wires where they are likely to be, and make the pattern and approach accordingly.
I have on several occasions skirted imaginary wires, and to my astonishment discovered them to be real - after landing. There are likely to be wires:
• Between two poles.
• Between a pole and a group of trees, or a single tree. It is not uncommon to find a telephone pole hidden by one, or a cluster of trees.
• Between a road and a house.
• Above any road.
• Going to any kind of a building.
• A narrow field with trees on one side and wires along a road on the other side, or a field with trees along both sides may have wires crossing anywhere along it's length. Avoid such fields if at all possible. The advice of landing well into the field is not applicable in these situations.
The safest assumption is to pretend there are wires around the entire perimeter of every field.
When crossing the boundary of a field pretend there is a wire there, then fly the approach high enough to provide plenty of clearance. It is not advisable to fly under a wire or wires as there could be a wire half way up the poles.
Ιf you must make your final approach over high tension power lines, be sure to allow for the thin ground wire above the power cables, which may not be visible. This thin wire can be as much as 20 ft. above the power cables. Beware, the heavy-duty power cables will tend to focus your attention. The safest tactic is to make the approach above the height of the adjacent pylons.
The best way to minimize the potential for having an unpleasant encounter with wires, is to pick a field out in open country, away from roads, trees and buildings.
SLOPES
Obviously, the best way to deal with slopes is to avoid them.
In our part of the country (The Finger Lakes Region in New York State) we pick fields in the valleys as the terrain on the high ground tend to be hilly. Fields in the valleys, for the most part, are reasonably flat and level, they also tend to be bigger. Furthermore, when selecting a field in a valley you will have more altitude available in which to find a thermal.
As much as we try to avoid landing on a slope, there may come a time when there is no other choice. When flying directly above a field, slopes are undetectable. Fields should be viewed at an angle of 30° from the horizontal. When viewed from 30°, terrain features are considerably more evident. Flying directly above a field which you are contemplating landing in is a complete waste of time and altitude. In spite of viewing a field at an angle of 30°, any detectible slope will be steeper than you think, and too steep for a down-hill landing. You must land up-hill, regardless of wind direction.
Landing up-hill is tricky business, and as with so many other skills we talk about, one that we don't have much opportunity to practice. Yet, it is imperative that we get it right, and the only hope to get it right is to be well acquainted with the proper technique and the pitfalls.
Here are the fundamentals of an up-hill landing:
• During an up-hill landing it is crucial to pick up extra speed on final so as to be able to fly up-hill parallel to the ground, prior to flaring. The main objective is to avoid flaring into the hill, people have sustained serious injuries from during this.
• The final should be started at the same place in the pattern as you normally do and at the same height (providing your normal height for starting the final leg is 300 ft,) then get the nose down to build up extra speed. What makes this maneuver even more challenging is that a strong illusion comes into play. When looking at an uphill slope on final, you will get a distinct impression that the glider is more nose-down than it is. Be sure to monitor the airspeed indicator.
• Go easy on the spoilers, chances are you may not need them at all. The speed will dissipate in a hurry once you start going up-hill.
• Do not use landing flaps, doing so will make the pull-up somewhat mushy which is precisely what you do not need.
• Landing uphill, into a stiff breeze is especially demanding, having the additional challenge of coping with heavy sink due to curl-over, wind gradient and turbulence.
Landing across a slope is not advisable. However, you could be faced with a situation where there is no other choice. If you must land at ninety degrees to a slope, keep in mind that the glider simply will not fly straight with one wing down. Landing from a conventional, straight-in approach will most certainly result in a vigorous ground loop and a broken glider. The only hope is to make the final in a turn to match the slope - easier said than done. The touch down must be on the upward portion of the slope so as to avoid rolling down hill.
FENCES
We are not so much concerned with wooden fences or fences with wooden posts, not that we want to run into them, but because they are quite obvious and should be readily avoidable. The type of fences we are concerned with are the single strand electric fences with thin steel posts, they can literally be invisible and deadly. Not that I want to over dramatize the subject, but some unfortunates have been decapitated. To avoid ever encountering this hazard:
• Never land or roll across two different crops.
• Never land or roll across the boarder of dissimilar textured surfaces.
A slightly different textured surface in one section of a field may indicate the presence of a fence. In many cases, such difference in texture is a result of grazing cattle having been confined to one section of a field by an electric fence - never cross such a boundary.
If you are approaching a fence or other obstacle on the rollout, and you realize that you are not going to be able to stop in time, the best course of action will be to ground-loop the glider. Remember to push the stick forward to lift the tail off the ground at the same time as you put one wing down, this will prevent the fuselage from breaking.
Life is simple. Eat, sleep, fly.
WIND DIRECTION
Check wind direction periodically during any flight. Knowing in which direction you will want to land will be one less thing you need to sort out when you get down to the level where you need to look for fields. Here are some means of checking the wind direction:
• Drift when thermalling is a good indication of wind direction and strength.
• Smoke is the best indicator, but there are not as many smoke stacks as there used to be.
• Pond or lake surface. A wind shadow (calm area) will be next to the upwind shore.
• Drift of cloud shadows across the terrain. Keep in mind that there often is a difference between the wind direction at the surface and at altitude.
• When hunting on a ridge, hawks tend to hover directly into the wind, making an excellent weather vane.
• Waves in high crops, or grass.
• The wind in a narrow valley between two ridges will be parallel with the valley in spite of the wind direction being at 90º to the ridge at the crest.
FIELD SELECTION
• Do not rely on small private airports.
The width of a mowed runway of a small private strip is often only wide enough for a tricycle landing gear, but too narrow for a glider with a 50 ft wing span. If there are fully grown corn, or fences on both sides, you will be in big trouble.
There is a certain amount of risk in relying on a landable waypoint in your GPS, unless you are familiar with it. Supposing you are at about 1,500 ft, and it looks like you will be needing a place to land. You dial-up landable waypoints. Sure enough, there is one a mere 6 miles away. You arrive with 500 ft in hand. "Oh shucks! Too narrow. Now what?"
• A cut hay field is the optimum choice.
• Use visual judgment - not the altimeter.
• Be conscious of the terrain at all times.
• Look for a group of fields when down to 2,000 ft. Never rely on a single field in the midst of hostile terrain, always have some options.
• Retrieve convenience should never be considered when selecting a field. Always select the best and biggest field within reach regardless of convenience of roads, gates, restaurants, bars, etc.
1. There are enough prerequisites to be met when selecting a field, no need to add any more.
2. If the farmer can get his equipment into the field to cultivate it, you can get the sailplane out.
3. Never compromise your choice of field for the sake of an easy retrieve. Even a ten hour retrieve is insignificant compared with a damaged sailplane.
• If spotting a high-tension wire pylon, look for the others. You want to be sure you know where they are.
• At 1,500 ft, turn the radio off.
The radio will not help you to land or stay up, and those are the only two things that matter. Even listening to the radio is distracting. Getting low away from home is the most stressful situation you are likely to encounter in your soaring career, and the tasks at hand will require your undivided attention. (See page 22)
• A field must be selected by 1,200 ft.
• Once a field has been selected, do not change your mind.
Once a field has been selected, stick with it. This is not the time for indecision. On closer scrutiny you may discover some obstacles or troublesome features you did not notice earlier, but your best course of action is to make the best of it. Do what needs to be done to accommodate whatever difficulties you may be faced with. Trying to find an alternate field at this stage would be inviting disaster, this is not the time to change your mind. From 1,000 ft you only have about one minute until it is time to start the pattern.
• Once a field has been selected, you can consider it your base of operation and look for lift, but be sure you can reach the I.P. with comfortable altitude.
• Οn your first few off-field landings do not attempt to prolong the flight below 800 ft. Once you reach that level consider the flight over and concentrate on the field and making a safe landing. Thermalling low over unfamiliar territory, with minimal experience is definitely not advisable.
CROP & SURFACE
• A freshly mowed hay field (without haystacks) should be your first choice.
• Low crops may be O.K. Land parallel with the furrows between the plants. If you cannot see any ground between the plants, or you can see wind waving the crop, it is too high.
• High crops should be avoided, especially fully grown corn.
• If you must land in high crop, pretend the top of the crop to be ground level, and flare accordingly.
• Cultivated fields (raked) or freshly seeded fields will be soft, but the advantage is that all rocks and holes are readily visible.
• Plowed fields with deep furrows should be one of your last choices, in other words, when desperate.
However, should you have gotten yourself in a bind and wound up in an area where all the fields within reach are too small, a plowed field may save the day, as the roll-out will be extremely short. The question whether to extend the gear or not is debatable. One claim is that an extended gear offers more protection for the pilot. On the other hand, an extended gear may cause damage to the under carriage and will bring you to a stop very fast exposing the glider to high "G" loads.
• Use pastures only as a last resort.
Pastures are a poor choice, not only because they are probably not cultivated, but animals can be a real problem. Horses are unpredictable and may get excited. Cows are curious, difficult to keep away from the sailplane and likes to eat it. If you must leave the glider surrounded by cows, leave the radio on with the squelch turned off and the volume up, they don't like noise. If there is a single cow in a field, it's probably a bull.
FIELD SIZE
• As a rough idea, if there are no obstructions on the approach, 500 ft. may be adequate, but if you need to clear 70 ft. high trees, you will need about 1,000 ft. and if your speed control is less than perfect you may need more. But adequate size depends on a number of factors, such as:
1. Slope.
2. Wind direction and strength.
3. Obstructions.
4. Type of surface.
5. Type of sailplane.
6. Level of skill and experience.
• Another glider in a field may not necessary mean it's suitable for you.
It was a national contest and a lot of us were coming back to earth in the same area. A fellow competitor had landed ahead of me and invited me to join him, but I declined. The field had been more than adequate for his ASW-20 but there was no chance of me squeezing in there with my heavy Schueman Libelle, with it's ineffective dive brakes.
• Your best bet is to pick the biggest, flattest field within reach.
• Visual illusions:
1. A narrow field will appear to be longer than it is.
2. A wide field will appear to be shorter than it is.
3. A long field will appear to be narrower than it is.
4. A short field will appear to be wider than it is.
5. If you have been low for a while, all fields will appear to be bigger than they are.
• A longer field is needed if there is a lot of wind and turbulence.
When the wind is at 20 kts or more, you need plenty of speed throughout the pattern, right down to the round-out and hold-off. Consequently, you will need a little longer field than you normally would.
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