downunder wrote: ↑Mon Apr 30, 2018 4:36 am
Matteo V wrote: ↑Mon Apr 30, 2018 4:09 am
Flying is solely reliant on engine, gravitational speed, or thermals to move and position the aircraft.
OMG, as a Paraglider pilot for years, flying paragliders is
NOT "solely reliant on engine, gravitational speed, or thermals to move and position the aircraft."
Sorry, you are wrong. Paragliding is reliant mostly on WIND. We do not go out when is zero wind. We need SOME wind. Looks like you've never seen a paraglider on the 'sloped' beach to clam such a bold statement?
Anyways....
How do we define a para skiing? Is it a pilot or a skier? Is Ragnarok sailing or skiing/paragliding/boarding/? Is a foil kite a paraglider when launched from a hill? Would you need a piloting/sailing license?
A triathlon Champ is exactly that. A multidisciplinary champion. If we approach to kiting in a similar way, it's is a multidisciplinary sport in own rights.
A can or worms btw.
I am having trouble putting my previous explanation in a simple way, but for you, I will give it another go. And to head this one off at the pass, gravity is a constant, not a media, in both explanations.
Sailing has 2 medias which are interacted with when positioning the sailing craft. They are
water AND air. There is a difference between the water's speed, and the speed of the air in sailing. This difference between the two is "leveraged" against in order to create movement in a preferred (or multiple choices of) direction. If there is no difference in speeds of these medias, no movement in a preferred direction can take place. Hold on to that thought for later.
Another key concept, which I did not mention before, is that a kiteboarder loses the capability to move in a preferred direction after the water's surface is disengaged in a jump. Or rather, once you jump and are only interacting with one media (air) you have no capability to change your course upwind, across the wind or downwind for a significant distance or to get to a distant location. Think of it this way, can you jump up into the air kiteboarding from the beach and make it out to that island that is across the river and slightly upwind? A kiter cannot, but a plane, or paraglider from the proper launch point, can. Planes and paragliders can fly there through the air alone, but kiteboarders have to sail there utilizing the push from the water and the pull from the wind, just like a sailboat.
Flight has only 1 media that is interacted with - the air alone, at least after takeoff. And after take off, all flying energy is provided by an engine, gravitational potential, or thermals (updrafts from a sand dune or mountain is not necessarily a thermal, but essentially performs the same function as a thermal). Again, in flight, there is no interaction with the ground (as an engaged separate media) after takeoff. And most importantly, after takeoff, the difference in airspeed vs ground speed is no longer important (or rather, essential) for powered or non-powered flight. After takeoff, wind speed at the interacting plane (geometric term) of the air/ground surface is no longer needed to reposition the plane or glider somewhere else. Put simply, without any part of the airplane or paraglider interacting between the ground and the air speed differential, both can still get to another desired location upwind, across the wind, or downwind.
Your specific reference to needing wind for non-powered paragliders has to do with the minimum takeoff airspeed over the wing. You can only run so fast, so taking off into the wind allows you to move at a slower pace with your legs, but the wing sees a higher speed airflow providing lift that you may not be able to generate without moving into the wind AND having some wind to help with your speed. There are many other launching advantages to having wind, but the biggest of additional note is that the wing can "self support" without the rider moving (wind holds up the wing), as in setting up the wings and visually checking the bridals before takeoff. If there was no wind, you would have to make apparent wind by running into the wind, likely backwards, to check your bridal system.
As for your reference to needing a sloped beach with wind (sand dune or mountain side), that is referencing an updraft created by a geographic feature. In this case, The air movement upwards is what allows the glider to be essentially be continually "falling through the air" without changing their altitude BECAUSE the air is moving upward over an obstruction AND upward relative to a constant altitude. If you have a problem with this concept, I can elaborate. It is pretty simple and you should be able to think it through but I will help if you would like. Again at the end of this explanation, I would simply state that the paraglider on the beach (dune) or riding an updraft on a mountain is still interacting with only one media (air) once they have left the ground. And while interacting with only one media, the paraglider can reposition themselves (go) to a different location, then back again, though only on a straight line parallel to a sand dune. Given the scale of a mountain vs a sand dune, more freedom of travel through the air is possible when the paraglider has a larger updraft on a mountain to work with. In that case, the paraglider can easily make it upwind or downwind given certain maneuvers to exploit the updraft created by the slope. As a note, updrafts are typically not sought after in kiteboarding, nor necessary to it. Updrafts can actually be considered detrimental to kiteboarding. (I do have one snowkiting location that does produce a stable updraft about 90% of the time - FUN, but not sailing - just boosting.)
downunder wrote: ↑Mon Apr 30, 2018 4:36 am
How do we define a para skiing? Is it a pilot or a skier? Is Ragnarok sailing or skiing/paragliding/boarding/? Is a foil kite a paraglider when launched from a hill? Would you need a piloting/sailing license?
If you can fly from a single takeoff point "Z", land at point "A", then takeoff from point "Z" again, but land at point "B", you are flying - so long as you do not interact with the ground or another media besides air to get to those points. The scale of the relationship between these points is important, but I am sure that could be reasonably defined for most cases.
Thus if you can both fly between both of those points (in you examples), or ski (interacting and applying forces) on the snow there with a kite over head, you could reasonably be consider both a pilot or a skier depending on which way you choose to get between points. However, you are only a pilot if you actually lose contact and no longer interact with the ground to change your location significantly.
Sorry for being so long winded, but you started this dumpster fire. I am just throwing my used motor oil on it, along with some empty paint cans, and a propane tank that I 'think' is empty.
And as always, thanks for your post.
