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Pattern And Approach
PATTERN AND APPROACH
• A conventional pattern during any field landing is paramount.
Just because you are away from home, and the critical gaze of your fellow club members don't get the idea that you don't need to worry about a pattern. A proper pattern is more important during a field landing than at the home base.
If you ever make a straight-in approach to a field and it doesn't scare you half to death, you don't understand the problem.
This is not the time for the type of pattern we see from time to time, where the down-wind leg is much too close and too low such that the base leg is replaced by a 180 degree turn
from the downwind leg onto final, and the final leg is virtually obliterated as that final turn is completed at a mere 50 ft - this is known as a ‘button-hook' pattern.
It's a good idea to get in the habit of making proper, well defined patterns with the downwind leg adequately spaced to allow for a proper base leg and high enough to enable you to start the final leg at about 300 ft, positively no less than 200 ft. The pattern can be either right-hand or left-hand whatever is optimum, pending wind direction and terrain. If there is a crosswind component, make the base leg into the wind, if there are tall obstructions on one side fly the downwind leg on the other.
• Do not start the downwind leg too high.
Some people have the idea that starting a little higher is better, but it isn't. If the correct altitude is 700 ft, then 1,000 ft is simply wrong. A correctly spaced, downwind leg is a critical element for a safe field landing. This is the only chance to scrutinize the field for rocks, holes, etc. so as to select a touch-down and roll-out area, and you'll be surprised how much detail you are going to miss from just a few hundred feet further away. Starting too high will also get you out of position for the rest of the pattern. Maintain proper distance during the down-wind leg so as to better evaluate the field and to leave plenty of room for a well defined base-leg.
• Don't rush the pattern.
Your first land-outs are likely to be a stressful experience and you may feel an urge to get it over with. Don't worry, the glider will come down in due time.
• Plan to land well into the field. (For exception, see page 5)
• If possible avoid making the approach over tall obstructions.
• If landing on a hill when the wind is 15 kts. or more, expect plenty of turbulence, and strong sink at the brow on the downwind side; do not extend the downwind-leg beyond the brow.
• Good speed control is imperative.
Do not confuse a low energy landing with a pattern flown at minimum airspeed. There is a lot of impetus on low energy landings. While it is true that modern gliders are slippery and we need to be extra careful concerning speed control, it is not advisable to fly the pattern at minimum speed. Always increase the speed in the pattern. You may be at the proper position and altitude, but if your airspeed is marginal the situation can deteriorate in a hurry should you encounter some heavy sink. With a little extra speed you are better prepared to cope with the unexpected.
The accidents which are caused by excessive airspeed are attributable to loss of speed control. To my knowledge no one has crashed because of approaching at an extra 5 or 10 kts. Be sure your speed is adequate to cope with the prevailing conditions, such as wind, turbulence and wind gradient. Select a speed that will make you feel comfortable and in full control. If it's an exceptionally short field, minimal speed may be necessary on the final leg.
• If too high on base leg use the ‘Reverse Pattern Technique.'
If you should find yourself hopelessly too high as you are about to turn onto final, implementation of the ‘Reverse Pattern Technique' will save the day.
Accidents due to overshoots are rare. Nevertheless, they do occur from time to time, which is a shame as they can easily be avoided. "Ah! This will never happen to me," you may say. It's not as unlikely as you think. Supposing, on one of your first cross-countries you are committed to a rather smallish field, you are surrounded by unfamiliar terrain and perhaps you have not been practicing landing without reference to the altimeter as often as you should have. Also, there is a tendency to be conservative and fly the pattern a little higher than normal during you first field landings and there you are - much too high. What to do?
The worse action you can take is to make a 360 degree turn, as it is difficult to predict the loss of altitude, and there is a real danger of becoming disoriented, especially in strange surroundings. Never lose sight of the field when in the pattern.
With the ‘Reverse Pattern Technique' you can salvage the situation without stress or strain. You simply continue the base leg to the other side of the pattern while edging slightly further back so as to make room for a ‘180' which will lead you on to a perfectly normal base leg from the other side. During this entire maneuver you can apply spoilers as required while constantly keeping the landing site in full view.
If you are not familiar with this ‘Reverse Pattern Technique' talk to an instructor, it may come in real handy some day.
• Landing diagonally across a field to increase the length of the landing area.
Providing the surface is suitable, if the field is short but wide, landing diagonally across the field will add considerable distance to the landing area. In a field 300 ft wide and 500 ft long, a diagonal approach and landing will add approximately 100 ft. Be sure to "clock" the pattern around to match the direction of the approach.
• Be flexible.
Although a standard pattern is important we must also be flexible. Supposing, while on the down-wind leg you notice the field has an undulating surface with 10 ft high crests, 50 to 100 ft apart diagonally aligned with the field. The prudent thing to do, irregardless of wind direction, will be to clock the pattern around such that you will be landing in line with and on top of one of the crests.
If you are short of altitude do not insist on a full pattern. In those situations the prime objective becomes to plan your flight such that the turn to final will be no less than 200 ft.
• Lower the gear.
If the sailplane is equipped with a retractable wheel, don't forget to lower it. This should be done at the same place in the pattern as you normally do, e.g. when entering the down wind leg. Then check it when on base.
WHEN TO OPT FOR A DOWNWIND LANDING
When the wind is light it may be advantageous to land downwind.
• As stated previously, if landing on a slope you must land uphill no matter what the wind direction is, whether the wind is minimal or otherwise.
• It may be better to land downwind with no obstructions on the approach than into the wind over tall obstructions.
• It may be a better choice to land downwind in a quality field than into the wind in a marginal one.
• If you are landing close to sunset do not land into the sun, regardless of wind direction, you will not see much of anything if you do. Fortunately, by that time there is seldom much wind.
On downwind landings there will be a significant increase in ground speed versus an into-the-wind approach, even in light winds. Prepare for a longer final by placing the base leg further back, so as not to get cramped.
LANDING
• Direction of landing.
The decision should be yours and yours alone. Another glider may have landed shortly before you got there, but don't let the direction in which that glider is pointed influence your decision making.
Years ago I made a field landing during a contest. The field wasn't the greatest and the landing resulted in a 180° ground loop. Another pilot arrived and did the same thing, so we were both sitting there facing in the opposite direction from which we had come. A third pilot prepared to join us. He assumed we had landed in the direction in which we were aimed and approached accordingly, going through some wires at the other end, ripping off the undercarriage. Of course, he blamed us for leading him astray.
• Be sure to stick with the touch-down and roll-out area you selected while on the downwind leg.
• Good speed control is imperative.
Be sure to maintain whatever airspeed you have determined to be optimum for the conditions, all the way to the round-out and flare.
• Always do a complete flare on every landing.
Since energy is proportional to velocity squared, even a small difference in speed at touch-down makes a significant difference in kinetic energy. Assuming a glider with a stalling speed of 40 kts landing at 45 kts. The extra 5 kts of speed would result in 26% additional energy to be dissipated upon contact with the ground. This number would go up to 56% if the glider was forced on the ground at 50kts.
If landing in high crop, be sure to flare completely above the top of the crop as if the top of the crop was the ground. If you are flying a sailplane with spoilers on the undersurface of the wing (fortunately, there are not too many of those left,) close the spoilers just as the glider is about to settle. If you do not retract them, inevitably the spoiler on one wing will contact the crop before the other, causing a vigorous ground loop. If you are flying a glider equipped with flaps, leave them in the zero position if possible.
• Once on the ground, apply full wheel brake.
Immediately after touch-down, apply the wheel brake to shorten the roll-out as much as possible. The longer distance you roll, the greater are the chances of encountering rocks and holes. Don't try to be clever and role up to the gate for convenience, it won't look very clever if you roll in to a hole and wreck the landing gear.
• Forgot to lower the gear?
If you realize you forgot to lower the gear as you are about to flare - leave it alone. Attempting to extend the gear at that point in time can easily lead to pilot induced oscillations and a broken glider. It is next to impossible to cycle the gear with one hand and remain totally steady with the other, and any slight twitching of your "stick-hand" will result in P.I.O.s. Worse, if you didn't succeed in getting the gear down and locked you will be more susceptible to injury. On the other hand, a smooth and gentle landing on soft ground, with the gear up is likely to cause very little damage, if any.
QUALIFICATIONS
So when will you be ready to tackle off-airport landings? Aside from being thoroughly familiar with the content of this booklet you need to be comfortable with the glider you are flying. There are no set minimum hours, it is the number of flights that counts. If you recently have moved up to a new type of glider a good rule is, 10 flights before going cross-country. Another factor to take into consideration is the difference in flying characteristics between types. Once you get into the higher performance gliders, the handling between types is very similar and the 10 flights rule may be overly conservative. The bottom line is, don't go cross-country until the task of flying and landing the glider is intuitive.
AFTER LANDING
• If you have landed at a private strip be sure to move the glider out of the way immediately so as not to block the runway.
During a Region III contest a competitor landed at a small private strip, abandoned his glider in the middle of the runway and left to make a phone call. The owner came back from a trip, was not able to land at his own airport and had to land someplace else.
This little airport is used extensively by the local glider pilots. We are very fortunate in having such places with friendly owners to resort to when the need arises, but let's not test their tolerance. We must be courteous and considered to the owners, or these oasis may not be available to us in the future.
If you are flying in a contest and have landed in a farmers field, there is a good possibility that if you can't stay up, there may be others with the same problem and you may get company. Before doing anything else, move the glider off to the side.
• Keep in mind that you are trespassing.
• If landing in a field with crop, next to a busy road, try to keep spectators out of the field as they can cause considerably more damage to the crop than your landing.
• Always contact the owner of the field if possible.
• If there may be a question of crop damage, take pictures of the landing path to defend any potential insurance claim.
• Be courteous, and respect the farmers property.
Ask the farmer for the best way of getting the sailplane out, and to get his permission
before driving the car and trailer into the field. If you cannot locate the owner and there is crop in the field, do not drive in there, use some other means of getting the glider out.
I landed once on an Amish farm in Pennsylvania and I was puzzled over the cold reception I was getting from the otherwise friendly appearing farmer. Come to find out, a glider pilot had landed on his property some ten years before. that pilot had driven his trailer through a field of crop without bothering to ask permission. The memory of that pilot's crude behavior was quite vivid even after ten years. I did finally manage to convince my host that all glider pilots do not necessary behave in the same manner.
• Prior to making the phone call, write down the directions to be sure they are complete and clear. Also, it is crucial to include the telephone number of the people you are with - enabling the crew to contact you in case they have any problems.
At first the farmer may very well view you as a rich city playboy (which may be entirely true) who has landed his expensive toy (also true) on his humble plot of land with complete disregard for other peoples property (hopefully, not true.) Here are some suggestion as to how you may conduct yourself to win him over:
• Be polite and courteous. Be sure to show appreciation for all his help including the use of his phone and don't forget to pay for the call.
• Impress upon him how fortunate you were that his field was there, enabling you to avoid a crash, and how happy you are not to have caused any damage.
• Emphasize how, in these rare emergencies, we always strive to avoid landing in any kind of crop.
• Show an interest in his farm. Ask questions and talk less about yourself.
• Take pictures of him, his family and kids next to, or in the glider.
• Don't forget to get his address so you can mail him copies of the pictures and perhaps a soaring calendar at Christmas to show your gratitude.
• Remember - you are an ambassador for the soaring movement.
The manner in which you conduct yourself will be a reflection on all glider pilots. A discourteous pilot will make a lasting impression on the locals, and future visiting glider pilots will be treated accordingly. You may have had a bad day but don't take it out on the farmer.
A superior pilot is one who stays out of trouble by
using his superior judgment to avoid situations which might require the use of his superior skill.
Arne J. Boye-Moeller
ELEMENTS OF A SUCCESSFUL FIELD LANDING
• RADIO OFF.
• EARLY DECISION TO LAND.
• VIEW FIELDS AT ABOUT A THIRTY DEGREE ANGLE.
• PICK THE BIGGEST AND FLATTEST FIELD.
• DISREGARD CONVENIENCE OF THE RETRIEVE.
• BE SURE SLOPE IS TOLERABLE AND LAND UP HILL.
• SUITABLE SURFACE, LOW OR NO CROP.
• TALL CROP, LAND ON TOP.
• ALLOW FOR WIRES AND FENCES.
• BE HEEDFUL OF THE AIRSPEED.
• AVOID LAST MINUTE INDECISION.
• WELL DEFINED PATTERN, RIGHT OR LEFT HAND.
• BE DISCIPLINED, YET FLEXIBLE.
• SELECT A SPECIFIC TOUCH-DOWN AND ROLL-OUT AREA.
• LAND WELL INTO THE FIELD.
• FULL FLARE.
• SHORT ROLL-OUT.
I would rather be in my glider
And think about God,
Than be in church and think about my glider.
Arne J. Boye-Moeller
