by
A. J. Smith
We're here because we seriously want to compete in soaring. We assume you've made that decision and you're a bit along the way to making that decision pay off. It's clear to us that many of you have elected to fly in the standard class. I wonder about the others. How many are considering the purchase of a sailplane and are still considering the open class? A few -- good! Great!
The problems are clear if you're going into open class. They're clear and, perhaps, not as serious as we just now make them out to be. We can put a fairly accurate number on the additional dollars required. It's somewhere between $1000 and $5000 extra to get into a competitive open class sailplane. You'll be able to compete with that piece of equipment for a number of years in spite of there being things like the Sigma around. Around! It's over on the other side. And they don't have enough money to ship it here for many contests. You really won't have to worry about it. We'll have difficulty with the Sigma and the like for a few years in international competition, but we'll discover ways to remain competitive with what resources we have.
In addition to more dollars, the open class requires more work, because, generally, you're talking about more area. With a very high aspect ratio, it isn't a lot more area. Until they open out these great whopping Sigma type flaps. You have to clean those and find a way to get inside the wing and clean it too, to get the accumulation of bees, dust and whatever, out of all those details. It's a lot more work, simply because the equipment is heavier, the systems more complicated, and all that sort of thing. You simply cannot fly any sailplane or operate any piece of equipment successfully in competition without constantly working on it, maintaining it, and improving it. This is particularly true if you're doing a new sailplane, as I'm certain the English are aware. But it's also true if you're buying an open class sailplane that's already in production such as the ASW-12, Cirrus, or whatever. You've a lot of work to do to get it competition ready. And, for the open class sailplane, it's a considerable amount more work than you might expect to put into a standard class machine. Considerable, but not so much that it should influence your decision between open and standard.
If you've selected a standard class machine and it's any-thing later than a K-6 series, you probably have a good competitive sailplane. Just now, thoughtful people, in evaluating sailplanes, say there is little difference between late model standard class sailplanes. That includes Standard Libelle, Elfe, Standard Cirrus, Phoebus, LS-1, ASW-15, and others in that family. They say further that you're likely to find a greater difference between two sailplanes of different types. I'm inclined to agree, from observation. We have seen considerable difference in Standard Libelles already. Some obviously are as good as any other standard class machine. Probably as a result of some amount of effort on the part of the pilot to properly prepare his machine.
That says to you, that you shouldn't go off in a swivet because Moffat says that your Standard Libelle is not going to win. You should, instead, go home and make your Standard Libelle the best one around. By the time you get it to that state, you'll probably have a better sailplane than 50 percent of the Standard Cirruses, or 50 percent of the LS-1's, or 50 percent of whatever. The capability of making the sailplane competitive in the standard class, now, with these machines, is in your hands. You can begin to exercise that capability by studying your own particular sailplane.
No two sailplanes really are alike. Not even two sailplanes of a single type -- Standard Libelles, again, to take an example. You should begin by checking your sailplane against its specifications. While Nick Goodhart says that all of them are basically, according to factory specifications, within the weights and aspect ratios that seem to him to lead to best performance, we really must admit that most of them are too heavy. Certainly much too heavy for anything less than Nick's standard thermal, which we should consider to be a rare good thermal even for most parts of the United States. Certainly for New England and our part of the country.
So, a weight reduction program is important. And it's not nearly so difficult as one might imagine. One Libelle pilot has taken a lot of weight, something in the order of 30 pounds, out of his machine. This is perfectly possible. The total weight reduction of a Sisu was something in the order of 45 pounds. This weight reduction will make a tremendous difference in the handling and performance of a sailplane. Come back from Marfa, for examples, and take out 20 pounds of oxygen equipment, a few pounds of emergency equipment, all of the bits and pieces you've had in the cockpit, including cans of Metrecal, all that sort of thing, and you can feel the sailplane climb much -better. This is when we're beginning to realize the best performance of a sailplane for the weaker soaring weather.
In addition, we have not seen a sailplane in which all the details are solved at a level that's sufficiently good for competition. It isn't so because the designer doesn't know how to solve them or the manufacturer's derelict or whatever. It's simply a matter of cost. You will quickly discover, when you improve all the details, that you will have spent, minimum, in the order of 200 hours on a new sailplane to make it really competitive. If you have a major smoothing work to do on a wing you can add another 100 hours for the first time through on that. This could add $2000 to the manufacturers costs, if he were to do the work during his production, The effect on his market would be bad.
Don't take anything for granted. Get airfoil coordinates from your sailplane dealer or apply pressure directly on the manufacturer for a set of templates. Check the contour of the wing. The most expensive sailplane being delivered to the United States now, in more than one example, has had a wing that was far from the true airfoil. You've got to start with the true airfoil, Airfoils are, outside of laboratory conditions, unpredictable. One can go through the development of a series of airfoils, a particular family of airfoils, and begin to see a certain favorable progression in the results of investigation of those airfoils. One would be tempted to bet on the outcome of the test of the next member of the family. One might suddenly be surprised to find the airfoil just doesn't perform. It's that bad. Don't make assumptions. Use templates, check the airfoil, and make it right. If anybody tells you anything else will work, don't listen. You've got to get the airfoil right. And then wave-free.
Detail work needs to be extended from aerodynamics into the comfort, handling, and instrumentation of the sailplane.
Some of you have particular comfort problems. It's fine to have the handbooks say that pilots are 170 pounds, but they should say something about pilot shapes. That's the designer's problem. European ships have tended to be tight in cockpit space. Now, to a degree, they may have overreacted and made the cockpits larger than need be. But, perhaps, this an asset. It gives one room to work in. However, even with a spacious cockpit you can do a tremendous amount to improve your comfort; and if you're seriously thinking about your own efficiency under difficult operating conditions, you know that when you're comfortable and your temperature right, you're like any other machine, you're working better. So comfort and ventilation are important factors to consider in the preparation of the sailplane. And, again, it's not difficult to visualize spending several days on these factors alone.
If you combine thoughts about the first evaluation of the sailplane, particularly its weight, with this development of comfort, you find specific problems. It's easy to buy a piece of foam rubber, for example, put it in the cockpit, and sink into it in blissful comfort. However, you may discover that piece of foam rubber weighs anything up to five or six pounds. if so, you've made a serious error. You should be able to solve your problem and get safe comfortable cushioning for something under a pound and a half But even a pound and a half is a lot. Cut lightening holes in it.
Improve the handling of your sailplane. Experience with different sailplanes of a single type indicates that, while control pressures generally are the same and the relationships between the pressures and responses generally are the same, no two, in reality, exactly are the same. Examine your ship for excessive control system friction. Examine it for excessive friction under all conditions of flight and loading. Examine it for flexing and looseness in the control systems. If you don't have a predictable and a constant reaction in the control system, you will be distracted. You'll not develop a subconscious flight operation that's desirable. You'll be working with unnecessary -variables. Eliminate play, eliminate friction. Again, if you have a problem in your particular sailplane in this direction, the solution can require considerable time. And, again, the most expensive sailplane being imported in the country now still has excessive control system friction; and the problem is apparently without a solution. The manufacturer says that there's nothing to worry about; in about two years it all loosens up!
The most important thing we have learned this weekend was how to develop a good sailplane total energy compensated variometer system. We should not only read Moore's paper again but also go through the exercise, preparing a system in the way he recommends. And this exercise, in effect, is typically the answer to our problems in competitive soaring. If we anticipate problems with sailplane variometer systems or with photographic procedure, and whatever, the best thing we can do is to go through the exercise of preparation and operation. We'll find that it's not nearly so difficult as we anticipate.
Compensated variometer systems really should do exactly what you've always read variometer systems do. It's difficult to explain just how important this is or how much easier it makes competition soaring. Your interpretation of the information you are getting from a good system and your utilization of that information will then begin to be the kind of subconscious procedure that we mention now in terms of the stick and rudder part of flying.
Let's hold just a moment on instruments and their interpretation and talk about the stick and rudder part of flying. This may help to explain the importance of a good variometer system.
You may realize, as you go into competition at this particular time -perhaps this will not be true in a few years -- that you're competing with people who have a tremendous number of flight hours. If not first in power planes, then certainly concentrated in flying sailplanes in recent years. And probably they have been for a long time at a level where they readily fly any aircraft simply by attitude. They no longer think much about exactly how the controls are working. It's subconscious in their systems. They immediately can fly a reasonably good handling aircraft of any type at any time. And fly it efficiently no matter how many engines, how much weight, and this sort of thing. What the stick pressures are, or the responses and whatever, is of little consequence. They may complain a little, but they manage to get the aircraft up and down, and do it efficiently. Get them into a good sailplane and the conscious stick and rudder bit simply disappears as a factor in their performance. You, too, must quickly get to that subconscious high level of performance. Practice.
The same thing is true and necessary in relation to the instruments and the information you get from them. You have to be able to accept that information readily and react almost subconsciously. If you have to interpret what a poor variometer system is doing, as we all have been doing for years, you will not be competitive. Perhaps we've learned mentally to compensate for the inaccuracies of a poor system, and we've constantly gone through some kind of arithmetic to determine just exactly what kind of thermal we've got. That kind of compensation is not a substitute for the real total energy compensated system. You're not only doing unnecessary work, you're being distracted from other tasks that are more important.
Gene Moore says it all in his paper. We've everything we need in it to get a good working variometer system. Put the instrument systems, the total energy compensated variometer system in particular, high on your preparation list. Give it top priority, even before the aerodynamic preparation of the sailplane, and certainly before comfort and handling.
Further, the preparation of calculators, charts, best-speed-to-fly rings, and all of this sort of thing is important. It's productive. Perhaps 100 percent reliance on all of these calculators, charts, and whatever is questionable; however, judicious use of them will increase our efficiency. Preparation, as much as use, of a best-speed-to-fly ring and final glide charts shows you what you should 'be thinking about and what you should be looking for in competition flight. And just knowing that -- going through the exercise of construction of these accessories -- having it reinforced in your mind that this is how the whole sailplane and soaring flight works, that it is a calculated and predictable performance, encourages you to take the next step. You can take the easy way out; you can buy John Williams' final glide calculator, for example, which does everything we have talked about here. From it you can know when to cut off your last climb, how to calculate your final glide, get your required altitude at any distance from the field, and so on, and so on. However, rather than to simply buy such a calculator and use it, I would prefer to recommend that you actually construct one. Better yet, buy one -- John's is a good one, but go through the exercise of constructing one yourself. That makes you understand the process better.
Work with navigational charts, the sectionals, or whatever, that will be used when flying in competition. Know everything that's included on a sectional. Learn to make notes on a sectional that will reinforce the information that's there or to add information that's important. Get all this information in mind so the chart becomes not a crutch for constant use during a flight but rather a tool used before flight to visualize landmarks, changes in terrain, changes in vegetation, changes in best lift areas, and so on. Learn to anticipate everything that you might see on a flight and particularly on distance flights. Learn to anticipate these things from pre-flight study of the sectional chart.
In addition, do a lot of practicing on the contest site. If you're going to Regionals, at least two days of practice prior to the start is good. For the Nationals, take the maximum practice session, probably in the order of a week. Fly the entire area. It's easy in Marfa where you have fixed turnpoints. It's still relatively easy in areas like Adrian or others in the middle west. The contest organization should be happy to tell you the general area you'll fly in and the turnpoints they've selected. Practice flying the area and not simply in irregular patterns but more directly on the courses you'll fly in competition. Knowing the terrain directly on course and the thermal sources that you might find, particularly if you're in an area where you'll do a lot of low altitude soaring is extremely important. Being able simply to find the turnpoint, again without referring constantly to the chart, is a great time saver.
The practice at a contest site, should be done in at least two specific phases, and perhaps even three. In the first phase, utilize the entire one week long Nationals practice session, learn the character of the total contest area.
The second phase, which might be carried on as part of the first, should concentrate in great detail on the immediate contest site: its thermal sources; directions for starts; the look of far-off landmarks and courses to them; how you need to make starts for that particular site; what final glides will be like -- they'll be coming in low, remember, from the opposite direction and the site might not look familiar; landmarks coming into the contest site from out on course; obstacles on final glide paths; and, very important -- thermal sources related to final glide paths. As the opening day of the contest approaches you should perhaps concentrate more on conditions in the immediate area of the contest site.
In the third phase, practice the evaluation you should do before your particular start of each task. The rules for launches are changing a bit. The tendency is that most pilots will have in the order of an hour in the air before they make the start. If we tend more toward speed tasks, you can begin to control this period of time. We should expect to see it extended by all serious competition pilots until they are, perhaps, in the air at least an hour and a half or two hours before the start. Use that time to "warm up," get comfortable in the cockpit, get over the frustrations of a too late launch by an inept crew and a poor tow pilot, and get smoothly into the business of flying the sailplane without thinking about it. Avoid flying with other sailplanes, except when they can help you to evaluate the atmosphere, and get on with the -business of reviewing or evaluating the day. This should be a systematic examination of the thermals ,and as thorough as time will allow. You should examine-the entire height of the thermals and know the strength of the thermal at any altitude for its entire height. Note as quickly as you can how that strength is changing and how the effective, most efficient or the best range of the thermal is changing. And it is changing. Constantly.
Pinpoint any layers of shear. You should have noted this in the weather briefings earlier, but try to pinpoint them in the air. Evaluate the seriousness of any shear layers. Decide if these shear layers are to be avoided.
Get all of this in mind. Establish working altitudes as nearly as you can in this hour before the flight. Check out thermal sources. Check out the clouds. If you have them, determine how they are working for that particular day. Know any change in wind velocity and direction at cloud base so that you have an idea of how the lift is going to be working in relation to the cloud 'bases. Determine, in fact, if pre-flight information agrees with what you really experience. Certainly, if you have time, make some practice starts. At least one. Most of our sites, when we really begin to know them, seem to have fairly fixed areas of lift and sink. If, as we had in Marfa this year, you have a long line of lift existing almost every day going into the start line, this is important information. In a Sigma you'd need only 3300 feet to start your run in. Go across the line at 3250 -- feet, not knots.
Finally, remember to develop the-necessary determination if you want to compete successfully, if you want to win. Then you'll have the drive necessary to do at least as much as we've outlined. If you're going to beat all of the others here, perhaps you have to do a lot more.
Question: (Steve duPont) Would you talk more about lines of lift?
Smith: Probably the patterns of lift almost anywhere are much more orderly than we visualize. This statement may generally apply both for flat terrain of the middle vest and the more rugged area near Marfa in the foothills and mountains. I think it's generally much better organized than Huth believe, if you read one chap's interpretation of his -philosophy. He writes that lift is as random as the trees in a forest and he flies accordingly. Perhaps he'd modify his flight for the United States in areas like Marfa, Reno, and whatever, where we have terrain that seriously affects convective lift. And even over flat terrain perhaps there's a pattern and an organization of areas of lift that's more pronounced than many of us imagine. While it's fairly easy to predict, from the textbook, the conditions which will produce cloud streets or regular patterns of lift, there are an infinite number of subtle variations and combinations of winds, convection and terrain, that promote regular patterns of lift.
Question: (duPont) Do you find them oriented?
Smith: We find them oriented in many ways, Steve. Perhaps the more successful pilots in competition are less inclined to say that things are exactly this way or that, you know. They tend to quality statements about the character of thermals and the use of weather. Probably what they're implying is that you've got to learn the factors you're working with and quickly sort out these factors of lift and weather for a particular day or for a particular moment. You may then suddenly discover a pattern. Perhaps you haven't seen that pattern before. Lift in lines is a pattern that occurs often. In our area it's lined up with the wind more often than not. In Marfa, for the first few days of our contest this year, it seemed to line up crosswind more often than not. On each flight, particularly before each start, go through an investigation. Anticipate the patterns you might be able to work with that day. Discover indeed if the lift is lined up. When you leave a thermal, try going right downwind or upwind. Observe the results. If the thermals are not lined up and indeed there are random cus, you may find that you get dumped and that probably the way to leave the thermals that day is to wind up a bit and go out the side -- much more successfully. Observe. Adjust. There are few fixed rules.
Question: There have been several references to working altitude bands. I'm curious to ask you and any of the others how strongly you discipline yourself to stay within these altitude bands that you have assessed to offer the strongest lift?
Smith: Very strongly, but with mixed success, really. You're trying very hard to stay in a range and being particularly conscious of heights in the thermal that are particularly difficult to get through. This almost always implies, or at least I infer from this, that it's a shear layer that you want to avoid. As I come down to one of those layers I may slow up and go to max L/D and try to pick up a good thermal. If I get down through such a layer and I know I've got another 3000 feet in which I might find good thermals, I might go back up to good cruising speed again until I get one. But I'm unhappy because I know when I get a thermal and cone up that I'm going to have to spend a lot of time to get back through that layer again. That requires another discipline. You must realize, if you want to get back up in the better lift, that you must patiently work with the ragged conditions in the layer. Nick, can you comment relative to European conditions?
Goodhart: I don't think we generally get multiple layers. The shear layer that we're always worried about is the one that's right near the ground, and you don't go through that unless you're going down, and I find that my flying when I leave the top of a thermal is to start off cruising optimistically on the assumption that the next one is going to be reasonably good of the standards that you've assessed for the day and to start off at a fairly fast cruise. But, as I cruise down, the probability of not finding the next thermal is beginning to increase and, therefore, you've got to start making your glide cover more and more ground and by the time I'm down to heights of the order of 2000 feet, I'm pretty near back to max glide because you're up against the probability by then that if you don't find one fairly soon you're going to go down, and so you've got to search the maximum possible amount of air. So all this speed ring calculation stuff, as far as I'm concerned, is tempered with the fact that you've got to search more and more air the nearer you get to the ground to increase the probability of not going down.
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