Vario
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Paragliding pilots like to know whether they are going up or down, especially when flying cross-country. Staying up interests them because it increases the likelihood of prolonging their flight. Going down interests them as well, since it tells them to move to a place where it is not going down (so fast). Preferably a place where it is going up. Unless, of course, they are desperate to go down. Which usually happens when it is too late to do anything about it, so we won't talk about it here.

These airy up and down movements cause similar moods in the the pilot's mind, resulting in interesting processes along the way. Addressing the various psychological aspects involved with these processes, would be an interesting exercise. It would also deviate your attention from the main issue here, so let me just state that good cross-country pilots would probably make excellent brokers as well. Both pilot and broker like going up, not down. Unless they are short of course, which pilots seldom are. Going up makes them all happy. The sky is the limit!

Going up create lots of enthusiasm, which encourages the up movement, even though it is just an air bubble they are riding. Pilots that missed yesterday's rally are ready to jump on the bandwagon today, as soon as the market opens. Flight plans are made and adapted, as more and more pilots effortlessly rise high above take-off. Flight plans are becoming bigger and bigger as the greed for distance overwhelms logic and common sense. Pilots below are now fighting for a place in the already overcrowded shuttle bus. Some of them are even offering double the usual fare to get to take-off now, instead of waiting for the next ride.

Going down on the other hand, makes them all nervous and could eventually lead to a widespread panic and crash for both broker and pilot. Of course you can profit from going down as well (acro pilots master this direction excellently), but you can not go lower than the bottom (i.e. you profit is maximised). Since the sky has no limit, most of us prefer to go up. Occasionally cross-country pilots really want to go down instead of up. This either means they arrived on goal (the end of their planned flight), simply had enough of flying (happens rarely, is considered a weakness or mental defect by fellow pilots, can and will be used against you during debriefing in the pub later on that day), desperately want to go down because they go up way too fast (Clouds suck! Especially big ones.), or have a major short position in stock. And, of course, any combination thereof. So, going up is the generally agreed way to go.

Unfortunately, humans are unable to sense being in uniform motion. It seems strange that men is able to build extremely fast computers that simulate the universe or predict the weather 50 years from now, clone creatures, land on the Moon, visit Mars, solve complex mathematical problems, memorise a telephone book up to 'g' in one evening (before the lights go out at eleven), conquer Macedonia, Greece, Turkey, Persia, and some of India at age 30, create a symphony of complexing beauty, annihilate the earth's population with just a single push on a inviting big red button, or even prepare a distant war with the Klingons, but somehow men simply can not sense going up or down. Such a basic, humble sense is just too difficult for humans. Why don't we have built in speed indicator nowadays? It would save law enforcement communities a lot of costly effort. Effort which could be used for fighting other crimes than speeding instead. When my mind wanders off during a flight, watching the birds fly without any artificial means such as nylon and Mylar, I often wonder where human evolution took a wrong turn. Or did it simply stop after running out of fuel somewhere along the track? As an individual, would I be able to correct the collective? Correct evolution's goal, the Great Five Billion Year Plan? Or even get the evolution moving again? Should I even try? What's the point?

Newton was not aware about paragliding in his days, but with his great mind foresaw the issue as early as 1687:

Lex I: Corpus omne perseverare in statu suo quiescendi vel movendi uniformiter in directum, nisi quatenus a viribus impressis cogitur statum illum mutare.

Impressively simple, isn't it? And the Latin (the scientific and philosophical language at that time), makes it sound even more impressive than it already is. For those who's Latin has become a bit rusty, Newton stated that in the absence of force, a body either is at rest or moves in a straight line with constant speed. It is the latter that addresses one of our human handicaps. We only sense force, not stability. We can feel that we are accelerating or decelerating, but not the constant speed at which we are moving, other than by indirect clues such as the wind in our face and visual references. Take away those clues, by stepping into an elevator for example, and we no longer know where we are going.

Riding the elevator, you can feel it accelerating up or down after the doors have closed. But you do not sense whether you are going up or down anymore as soon as the elevator reaches a constant speed, i.e. when it stops accelerating. The same happens in rising and sinking air. When a bubble of rising air has a constant speed, you can not feel whether you are going up. You can only observe it after a while by looking around you. Imagine the terrible thing that could happen: a pilot is going up in a bubble and, being completely unaware of this, leaves it! Instead of dreamily bubbling along, the pilot has created her/his own descending nightmare. The horror!

To overcome this sensitive handicap, the variometer was invented. This nice device is also known as rate-of-climb indicator, vertical speed indicator, vertical velocity indicator, or just vario in order to keep it practical. It is a simple but clever piece of equipment that is often combined with an altimeter. It used to be quite big and still is (Big is more impressive, isn't it?), but is also available as a wrist computer or a small accessory that fits on your helmet nowadays.

A vario measures the pressure (and more modern ones the altitude indicated by GPS) at specific intervals. Every second or so for most of them. It gives a nice reassuring (range of) beep(s) when the pressure decreases, i.e. when it goes up (and presumably the pilot as well). The faster you go up, the happier it starts beeping, helping you in finding the centre of the thermal. This is the spot where it usually beeps fastest, depending on your banking angle and strength of the thermal. Pilots not only want to go up, they want to go up fast in order to... well, to do what exactly?

If you have a really strong thermal, say 10 m/s, varios transform those happy beeps into a mad mitraillade of sound. Most pilots love that sound. It makes them happy because it makes them go up. The more furious the sound, the faster they go up. It is the sound that defies that dreaded gravity. I have seen Pavlov pilots starting to drool and look up, without even being attached to their glider, simply because they heard the sound of a vario beeping (installed as a ring-tone on someone's phone). If only Newton would have known...

I hate that sound. It disturbs me. It deranges me. It freaks me out. To make it even worse, a lot of pilots seem to be hearing impaired. They have the volume of their vario set at such a level that you can hear them coming, long before you see them. Just as those magnificent Mirages that lighten up your boring flights with a fly-by now and then. As soon as I hear those police pilots coming with their sirens screaming, I leave the supposed crime scene and go thermal somewhere else. Somewhere quite, with just the birds and wind talking to me. If they keep on following me, their sound is likely starting to really disturb me. Since these pilots seem unable to think for themselves, I usually have no trouble in taking them along to a difficult transition or a nice blue hole. After sinking out together, I perform a low save (this is the tricky part), and get on with the flight. Some of the pilots will still be screaming at me, but since they are on the ground now, they won't follow me anymore and silence will soon have returned.

Yes I know, it probably is a mental defect, but I prefer to fly without a vario (or a GPS for that matter). It gives me a better feeling for what is happening in the air. Last but not least, the preceding observations and conclusions (or even sabotage as some might correctly assume), is not meant as an insult or disrespect to pilots who fly with a screaming vario. On the contrary, I am rather thankful for their presence. Since they force me from the usual routes, my knowledge of unusual but splendid routes has greatly increased.

As you may have noticed, I enjoy the silence of flying. This is not quiet silence, but that is exactly the beauty of it. It is the silence of the wind caressing my wing, my face, as well as any changes thereof. Changes that tell me to act, before they act on me. It is also the silence of a swift flying by. The cry of a vautour fauve kilometres away. The laughter of choucas when playing in a thermal (or a rotor, they are not very picky and have fun anywhere in the air). The sound of a rooster crowing or a dog barking way down below, upwind in the valley. Of course they are upwind, how else could I hear them? In fact, there are so many clues available that it is possible to defy Newton's first law: pilots can sense whether they are uniformly rising or descending in the air. You just need to try. On the stock market, the most valuable commodity I know of, is information. It is the same in the air. Especially if you want to ride the rally. But how to get this information? From inside trading of course: use your senses.

If you are near a mountain, a ridge or anything else that gives you an adequate vertical reference, you do not need a sixth sense. You can actually see that you are going up. Have a gentle (evening) soaring along the local ridge, I find it hard to understand other pilots need a beep to tell them they are going up. Of course they are going up! They are soaring, aren't they?

When you lose the immediate references near to you, a background comes in handy. By comparing the vertical separation between a fixed point somewhere between you and the horizon (or any other far away reference), you can see whether you are going up or down in relation to this reference. When you see more and more of the far away reference (i.e. when it is rising: you are getting to see the whole mountain in the distance, not just its peak), you are going up. Think of a watchtower: the higher you build it, the further you can look. When you see less and less of your far away reference (i.e. the mountain peak in the distance starts sinking out of view behind the mountains in front of it), then you are descending.

I like simple solutions that are effective. A background check is one of them. However, it only works well with shallow angles, i.e. when there is little separation between the height of the near and far reference. As you rise above the mountains, i.e. above your near references, a background check becomes less and less effective. By moving your near reference further to the horizon, you can still use it, but the noise in the measurement will increase and it becomes less precise. To compensate for the increasing error, you have to gain relatively more metres to notice a difference compared to flying at lower altitudes. This means that background checking becomes unreliable as soon as you are very high above the mountains. This sounds worse than it actually is. I do not find it a problem, really. Who cares about rising or descending air at this altitude anyway? Warm hands aside, what do you want more if you are flying at 4400 m altitude and see the snowy summits of La Meije below you? 5000 m? 5863 m? What's your next stop, heaven? It is freezing cold up there!

A background check is very useful when you fly in a straight line, having your reference in view all the time, such as during transitions. Unfortunately, thermalling usually involves circling like a circus horse in a far to narrow ring. Unless you are able to perform a neck breaking circus act, the circling only allows one background check for a specific spot every turn. And if you drifted with the thermal, it might give you the wrong idea about your gain or loss. So, we needed something more precise and continuous to help us centring the thermal.

Let's get back to our senses. Besides the lack of sensing speed, humans are adequately equipped to observe the world around them. You still can see, hear, smell, and feel the air. Any manner of observing (changes in) air movement helps you in determining what is going on. Here are just a few:

The above list is far from exhaustive, but you get the picture. You will probably have or find clues yourself. The ability to be in direct contact with the sensible information around me, is the main reasons why I prefer to fly with an open helmet. Full-face helmets tend to dampen a lot of the available clues. Too much for my taste, that is. Not only when thermalling, but especially when taking off (i.e. regarding wind strength and direction).

Do I fly better without a vario? Yes, definitely! Better in the sense of enjoying the flying. I am less sure about flying better in the sense of performance. All I can say is that I do not see enough difference that justifies flying with a vario for me. It could be different for you. I have flown with vario pilots that had the same (or much better) skill level than I have. Some of those were equipped with varios that exactly told them their optimal glide ratio, while I just have to guess. I have outflown them on many occasions, and the opposite has happened just as many times. The only difference I have seen so far, is that pilots using a vario are often better at finding the last 100 to 200 metres gain near the top of a thermal. It is the spot where the air usually becomes less coherent. The information I get at this point is often too weak or confusing to make much sense out of it.

Do I need those extra metres? Usually not. I try to get as heigh as needed, or just a bit more to be sure, in order to make it to my next objective. Especially when fighting your way against a strong upper wind, getting high does not help you that much. You will spend more time going up than forward, only to be more opposed by the wind as you get higher. On a windy day, your progress will be less fast compared to pilots who stayed low. At the same time, you risk to be sinking fast when you leave the thermal, with little to no ground speed. The most frustrating experience however, is likely to be the fact that the pilots who left the same thermal at lower altitudes (thus earlier) than you, are arriving earlier at the next thermal. Leaving behind those who milked the last thermal to the last drop. Not that I mind being left behind, it is just that I never really understood MacReady until I started flying without a vario.

A vario comes in handy on a blue thermal day. Those days when there are little to no clouds to tell you where the thermals are. You might be flying into a weak thermal and miss it, since it was to weak to trigger your senses or to centre correctly. This usually happens when you (need to) find a thermal during a transition of a large valley or plain. Since your vertical references are far away, it is difficult to conclude whether you arrived in a thermal or just bumpy air. Loosing valuable altitude by spending too much time circling in bumpy air, could put you on the ground. Missing a thermal because you think it is just bumpy air, could do the same. Do not let this discourage you though. I have managed these kind of transitions after a little practice.

Weak air is probably the most difficult issue to get used to when flying without a vario. It is not easy to understand a thermal when it is only whispering to you. You prefer thermals talking to you loud and clear. And contrary to human communication, you won't mind when a thermal is shouting at you at the top of its voice. Thermalling becomes even more difficult when thermals are weak and chaotic at the same time. The chaotic movements tend to drown out the small signs that are important to notice. This considerably lowers my perception's signal-to-noise ratio. The noise is easier to filter out when you have a vario. On the other hand, by really focussing on the tiniest movements in the air, I have managed to climb out of these conditions while other pilots remained hostage. So, I am not really sure about being at a disadvantage here.

What I do know, is that making the right decision is far more important than optimising your ascent rate. Finding the next thermal is far more important than thermalling efficiently. A fact often forgotten by beginning pilots that try to compensate for their embryonic skills by using sophisticated varios that cost a fortune, but won't make them fly better. A good decision will eventually take you higher and further, with or without a vario. A lousy decision is likely to ground you, with or without a vario. Just remember: we are all just one trade away from humility.

In low saves, flying without a vario is a big advantage. There are lots of references and clues nearby to observe whether you are going up or down, all the time. This allows you to you to focus on even the tiniest movements in the air that could save your flight (and your day as well). Pilots that fly with a vario often tend to hear the 'I am going up' beeps, but do not notice that on average they are going down nonetheless. Unless of course they have set there sink alarm to a desperately low value. However, that is usually not the case, since it would drive them mad during normal flight. And even if they see that they are going down, pilots might not derive the right conclusion from that observation. Humans have defects, as we already observed at the beginning. One of them is to ignore perceptions that do not fit in with expectations. Until it is too late, that is. The number of pilots that ended up hugging a tree after assuming they were going up, is larger than you would expect from mammals equipped with the most sophisticated brain on earth.

Some pilots prefer to keep their vario and just switch off the sound. It allows you to focus on all the other available clues without being disturbed by beeps. In case of doubt, you have a quick glance on your vario. It seems like a good compromise, as long as you are aware of the risk. If you lack confidence, that quick glance can become a prolonged stare that could last the whole (search for the) thermal ride. Looking at your vario for longer than just a split second now and then, significantly increases collision risks with fellow pilots, hillsides, mountain summits, clouds, a large lonely tree, et cetera. Irritating as they might be, the beeps are their for a reason you know.

A compromise often combines the worst of two things, instead of the best. Those old mono skis are a good (bad?) example here, or just think of the Einstein-Monroe joke. Choose a manner which suits you best and have confidence in it. Go for flying with or without a vario, but do it with all you heart. Do not end up messing up somewhere in the middle, somewhere in a tree or in someone else's glider, just because you were looking for too long at your vario, your GPS, your girlfriend's picture, the weather bulletin, or whatever else seemed so important at the time, but in retrospect was not important at all. Looking around you is. Always.

I am not ordering you to fly without a vario. It is free flight, remember? Neither will you incur my eternal wrath and damnation when flying with one. My sole intention is to show you that there is a different way of thermalling, of flying. A way that is excellent for ordinary cross-country flights and even better for vol bivouac (less weight, no battery issues). A way to really have free flight, not to be tied to an instrument.

Give it a try! There are so many pilots attached to their electronic equipment such as a vario, that they will miss vital clues that could have kept them up (especially during low saves), while on the other hand they are getting clues that are completely unnecessary. Who needs a mitraillade of bleeps when thermalling in a 8 m/s thermal? Chances are that you will be more than aware of the fact that you are going up without hearing those beeps.

Centring in such a strong thermal might even be easier without a vario. A vario needs some time to measure the height gained or lost since the last measurement. This delayed response decorrelates your observation from actuality. In English: while your vario is still happily beeping, your wing might get whacked because you just lost the strong narrow core of the thermal. In these, as well as many other situations, you will probably be better off feeling the wing's movements and adapting to it, rather than listening to beeps.

Unless of course you are a competition sky god and use the vario to squeeze the last possible inch out of a thermal that you are already perfectly centring on feeling alone, or need to find the most efficient rising part of the thermal to optimise your glide ratio to the next thermal in order to be there 17,4 seconds earlier than your fellow competitors in the current thermal. But that is competition, not vol bivouac. Why should you optimise and race, while you can enjoy a good flight?

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2009-12-25