Glide can be measured as the angle of descent of a disc after apexing in flight. I have a mathematical analysis of glide that will be published in my book on Disc Physics.
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^ This. Glide is how much the disc maintains loft after it hits the apex, the disc is no longer rising.Glide can be measured as the angle of descent of a disc after apexing in flight. I have a mathematical analysis of glide that will be published in my book on Disc Physics.
You are correct in that if you draw a free body diagram of a parachute falling, there's certainly a force vector pointing up due to the resistance of the air on the parachute. If you want to call that lift go ahead.
I was referring to lift in the sense that a disc, like a wing, discs get lift from the differential in pressure caused by air passing over it the upper and lower surfaces at different speeds as it travels forward.
OK, I've been thinking about this since I posted that link yesterday evening. What makes different discs of the same mold fly differently when new? The parting line height does. Could the higher PLH, which makes the disc fly more overstable, be causing the leading edge of the disc to force more air downward, in turn causing the center of lift to be more forward of the center of rotation, which in turn causes an earlier and/or harder fade?
Basically could a higher parting line just indicate a "steeper" wing? Could the massive overstability of discs like super flat Champ FierBirds just come from a lift bias towards the leading edge of the disc due to more lift on the front? All along I've thought that discs like that lacked "glide" because they lacked lift. Could it really be because they have too much, at least at the leading edge?
To tie this thought in with the OP, could a working definition of "glide" be how well "balanced" a disc flies?
I'll repeat what I posted earlier. In an overstable disc, precession takes over much more drastically, causing the disc to tip in the air. This causes the lift vector to move so that the lift it's generating is no longer in direct opposition of gravity.
Glide can be measured as the angle of descent of a disc after apexing in flight. I have a mathematical analysis of glide that will be published in my book on Disc Physics.
As for the first paragraph I quoted, what else would you call the upward force acting on a parachute?
The flight ratings are relative to disc speed so they are indeed reflected. It's like saying a Boss is an overstable disc. Also you shouldn't throw a putter nose up for it to glide far, that's actually counter productive. A putter nose up will glide further than a driver nose up, but that's because a putter has a less sharp nose. If you throw a putter and driver with the same amount of power, say 25% power, the putter will glide out further than a driver.
That definitely makes sense about the flight ratings being relative to disc speed. However, I'm pretty sure (horrible memory) that I saw a video where a pro was talking about driving putters. In it, they mentioned how putters are supposed to be thrown slightly nose up for distance.
Buoyancy?
OK, I've been thinking about this since I posted that link yesterday evening. What makes different discs of the same mold fly differently when new? The parting line height does. Could the higher PLH, which makes the disc fly more overstable, be causing the leading edge of the disc to force more air downward, in turn causing the center of lift to be more forward of the center of rotation, which in turn causes an earlier and/or harder fade?
Basically could a higher parting line just indicate a "steeper" wing? Could the massive overstability of discs like super flat Champ FierBirds just come from a lift bias towards the leading edge of the disc due to more lift on the front? All along I've thought that discs like that lacked "glide" because they lacked lift. Could it really be because they have too much, at least at the leading edge?
To tie this thought in with the OP, could a working definition of "glide" be how well "balanced" a disc flies?
Glide can be measured as the angle of descent of a disc after apexing in flight as it's velocity is rapidly decreasing. I have a mathematical analysis of glide that will be published in my book on Disc Physics.
^ This. Glide is how much the disc maintains loft after it hits the apex and loses velocity, the disc is no longer rising.
Here's the issue I have with glide. People often talk about how slower discs have more glide, but Innova's flight ratings don't reflect that. More importantly, however, the discs' flights don't reflect that either. If you throw a driver and a putter on the same angle, flat, the putter will start to drop sooner. To get the putter to glide far, you have to throw it nose up/at a slight upward angle. So, I basically am no closer to being able to accurately describe glide now than I was before this thread.
A disc can increase velocity after the apex though.I added the blue parts -- to me glide is relevent when the disc begins to slow way down, yet still travel forward. I know that a disc cannot increase velocity (unless thown downhill) but glide is visually qualitative when the disc is slowing down.
i.e. The best, glidiest paper airplane in a given lot will contact the ground the farthest from where it's thrown the instant after its velocity reaches zero. The ground contact didn't cause the airplane to stop moving forward, the air did.
just my thoughts
Putters need more height to go far as they slow down faster, so they can use their glide after the apex to keep penetrating forward. Drivers rely more on maintaining their speed and they don't tend to maintain a forward penetrating trajectory well after the apex and will curve.That definitely makes sense about the flight ratings being relative to disc speed. However, I'm pretty sure (horrible memory) that I saw a video where a pro was talking about driving putters. In it, they mentioned how putters are supposed to be thrown slightly nose up for distance.
I'm a little confused:
Are you referring to the parting line as in where the mold comes together? If the disc is of the same mold wouldn't this be in the same position?
As for the first paragraph I quoted, what else would you call the upward force acting on a parachute?