If you're in the market for a fancy paraglider vario, you probably know what you are looking for. You've probably seen one, looked up some info on a specific model or even borrowed someone else's for a flight or 2. You might want to give this page a miss, you don't need much more introduction. :-)
Otherwise, keep reading or even scroll down until you see a heading that looks interesting. This is one of the longest pages on this website!
Ok, if you're still with me, you probably don't know much about this stuff.
Perhaps you're curious as to what kind of info a modern paraglider vario can provide! I'll mention a few specific models but really it's just an overview of all the various functions. Gadget freak heaven.
Don't worry if some of the stuff below goes over your head. There's some info that's relevant to people with no flying experience. And other stuff will only make sense if you've had some soaring experience, but just have never really looked into instrumentation. Take what you find interesting, ignore the rest till later.
Let's get those specific top-of-the-range models out of the way first. If you're interested you could just look them up using your favourite search engine. There's the Flytec 4030 Race Vario, last time I looked the going price was US$900. Mmm you can buy a 3rd-hand but roadworthy car for that much here in Adelaide. Then there's the BRÄUNIGER IQ ONE+ from Europe, don't have a price but I'm sure it would set you back plenty of euros. It's at the top of what they term their Intelligent Flight Instruments line. And there's the Aircotec XC Trainer. This is actually a paraglider vario and GPS unit in one.
This brings up a point. 'Varios' these days are really Flight Instruments that offer so much else besides the variometer function! Category by category, I'll try and summarize what's currently available, without reference to any specific boxes. Just settle back for a good read! As you might have noticed, this site is heavy on words, light on pics. :-)
That's basically all a paraglider vario does. Just how fast are you rising or descending, relative to the ground? I don't think any aircraft instrument has as many units of measurement as the variometer! I have personally used varios in sailplanes which use ft/min (100s of feet per minute), m/s (meters per second) and knots (nautical miles per hour). Not sure if ft/sec has ever been used, I wouldn't be surprised. Oh yes, and some U.S. sailplanes have varios calibrated in mph (miles per hour).
And then there's the old British type that's calibrated in furlongs per hour. Just kidding.
The indication of a modern paraglider vario can be displayed as either a digital readout or a fake analog clock. The readout looks like a needle in a circular guage, but it's done with modern electronic displays.
Analog gives you an instant impression of how weak or strong the lift is, but reading the numbers from a digital display can of course give you a more accurate reading. Particularly if the readings are averaged.
Averaged? This is a useful feature to have so you can have a better idea of your real rate of climb. Set to a short averaging period, it has the effect of ironing out all the little fluctuations in the thermal's strength. This makes it easier to mentally plot the profile of the lift area so you can shift your circles to coincide with the thermal core. If set to a really long averaging period, it's a sort of 'achieved rate of climb' meter. Usually a lot less than you thought! I seem to remember an old rule of thumb that by the time you get to the top of a thermal, your real rate of climb is about 1/2 to 2/3 of the vario readings you remembered seeing.
Sometimes, a paraglider vario will offer Total Energy Compensation. This feature requires a little probe that sticks out into the airstream. Once adjusted properly, this allows the pilot to filter out the effects of the paraglider's own motion on the vario reading. In other words, the vario will always read out the motion of the surrounding air. So, for example, if the pilot steps on the speed bar for a while, in 2 m/s up, the vario will continue to read 2 m/s up.
An ordinary vario reading would then sag a bit as the paraglider started to descend quicker. The opposite case is a 'stick thermal', so called because vintage glider pilots would slow down when entering lift but then get fooled by the really high indication of the vario. Plain inaccurate flying would sometimes produce stick thermals too, even in still air!
An altimeter is one of the basic flight instruments, and these 'fancy varios' as I've called them usually include various altimeter functions. That is, the ability to know precisely how high above sea-level you are. Or how high above a designated point, such as where you took off from.
A recent development is the final glide altimeter. This readout tells a pilot how high above or below the final glide path they are, as they race towards goal. Unexpected lift can be converted into speed. Or the pilot might be forced to slow down in order to just make it to goal without landing!
By using multiple altimeters, pilots can see both height above goal, and height above final glide for example. Or maybe height above sea level and height above goal, and so on.
Altitude can be obtained from either measuring atmospheric pressure, or by using GPS in 3D mode. More on GPS further down...
A barograph feature lets you look over a history of the altitudes you were at for the entire flight. These traces can be uploaded to a PC for analysis later. For example, what was the highest point in the flight? Which climb was the fastest? When was the last thermal of the day?
The scan rate is usually adjustable too, so you can see altitude changes every few seconds for short flights if you want to. Or at the other end of the scale, cram an entire 7 hour flight onto the one trace with no fine detail!
A clock is usually included in a good paraglider vario unit, and also a means of recording the total flight time. Better than glancing at your watch and then forgetting what the time was, after you are on the ground again! A stopwatch feature is also handy, some would use it to time climbs in thermals. So there can be up to 3 time-related functions built into the unit.
Yes, some paraglider vario units contain a built-in thermometer!
Essential for competition pilots, a final glide computer tells the pilot when the goal is achievable without another thermal, and often additional information such as the best time to leave the last thermal. So the pilot might be climbing away, late in the afternoon, and the final glide computer says 'if you leave now, you can just make it'. If you did leave then, you would have to fly at the Best Glide Speed for your paraglider.
However, if the pilot continues to climb, there comes a point where the computer says 'if you want to get there as quickly as possible, leave right now!' The computer then gives you a 'speed to fly', which is somewhat higher than the Best Glide Speed.
Any more time spent climbing would just result in a later arrival time at the goal, no matter how fast the paraglider was flown. If you fly too fast, you will land short of the goal!
Wow, what a long way this is from mere variometer readings. Real GPS navigation, quite similar in function to what is installed in the cockpits of commercial aircraft, is available to paraglider pilots. In a nutshell, you can simply see where you are on a moving map. Relevant speeds, distances and headings are constantly updated as you watch. Very cool. And very practical in the hugely restricted environment of a paraglider in flight.
How does it do it? By timing the signals from the nearest 3 or 4 GPS satellites that happen to be overhead at any time, and computing your position via a process known as triangulation.
Going right into everything you can do with a GPS unit is beyond the scope of this web-page. And it's quite a bit, I know that from my stint as a virtual airline pilot with Qantas Virtual Airlines. The simulator I was using did a great job of re-creating all the workings of a modern GPS system.
Anyway, I will mention that both 2D and 3D GPS information is available to some modern paraglider vario units. This means that not only position on a map, but altitude as well can be derived from the GPS system. This opens up new possibilities for information that serious cross-country pilots would find useful.
With all the info a modern paraglider vario unit provides, it would be a shame to lose it all after every flight. So it's not surprising that these units can dump useful information to a PC. Some units allow the logging of more types of information than just altitude changes. Purpose-written paragliding software such as Flychart Professional on the PC can organize, display and analyze the data to enable lessons to be learnt from the pilot's flights over time.
Without even looking at the doco on these programs I can think of a few simple things that could be useful. Filling out a logbook, either stored on the PC or the old-fashioned paper type. Maintaining personal records such as highest climb, longest distance, longest duration. Seeing what went wrong with your latest cross-country attempt...
For the more technically inclined, it's even possible to transfer performance information from a unit such as the Flytech 4030 Race to Flychart to build performance polars, which can then be transferred back to the 4030 Race. In plain English, this means that your paraglider vario can 'learn' precisely how your wing flys at all airspeeds. Hence, you can get back very accurate information during your flights as a result.
Just to give a very simple example, a heavy pilot and a lighter pilot flying identical paragliders would actually represent 2 slightly different gliders in terms of performance characteristics. Using the process described in the previous paragraph, both these pilots could extract the most out of their paragliders during a race.
As if all this wasn't enough, the functions on at least one of the systems mentioned are largely programmable. For example if a vario readout doesn't quite suit you, you can fiddle with the range, response rate and so on. I can imagine some guys spend more time programming their paraglider vario unit than actually reading it in flight!
Hope you enjoyed all this stuff, you must have if you persisted right through to this last paragraph! ;-)