Dome Height-“Domey” vs. Flat

While there is a common belief that discs that have higher domes are more “flippy” than flatter discs, (especially when they are variations of the same model) this is only partially true.  Discs with a higher dome will generally be less high-speed stable than a flatter version of the same disc, but the high-domed disc will also be more apt to flex out if it gets turned.  A flatter disc is more difficult to turn but it is more likely to keep turning after the turn begins. Late in a disc’s flight it has lost a lot of it’s initial rotation and velocity and as the disc slows, a disc with a high dome will be more apt to stay in the air and fade back left.  Wind will affect a disc with a higher dome more than a flatter version since the taller profile will be more affected by the wind.

Rim Width- The Gyroscopic Characteristics of Mass Distribution

Discs with wider rims have greater mass distribution on the outer edge of the disc and will have greater gyroscopic tendencies than discs with narrower rims and more mass towards the center of the disc.  That is, a wider disc will be more difficult to turn over, but will be more apt to continue to turn once it has been turned.  A wide disc will also be more likely have a strong fade at the end of its flight as the disc slows down.  Also, the wider the rim, the more the disc will change its flight characteristics due to changes in disc mass. 

A wide rim disc holds a large percentage of its mass on the rim. If you take two discs of the same wide rim mold, one heavy and one light, they will have roughly the same mass on the flight plate (it can only get so thin without collapsing) and the majority of the mass difference will occur on the rim.  A disc with more mass on the rim exerts greater gyroscopic forces than a disc with less mass on the rim (assuming they are thrown the same).   Discs with narrower rims carry less mass on the rim and more on the flight plate so the effects of mass changes will have smaller effects on disc stability between different discs of that mold.

Air Friction- The Effects Of Plastic On Disc Flight

Disc plastic has a great affect on disc flight characteristics due to the varying amounts of air friction between plastic types.  Lower priced standard plastics will have the most air friction when new and will build additional air friction more quickly as they break in.  Higher priced premium plastics have the least air friction and also build friction more slowly through their aging process.  While disc stability is dominated by the disc’s shape, two discs of the same mold produced in different grades of plastic will have noticeable differences in their flight characteristics.

The disc’s ability to move in the direction of spin will increase when there is greater air friction on the disc. The characteristics of plastic that help a disc flatten from a hyzer and/or turn over is similar to throwing a curveball with a baseball.  The greater the air friction on the baseball, the more the ball will “bite” and help the ball to move in the direction of the spin, in this case, top spin causing the ball to drop.  It is easier to flatten a hyzer and/or turn over a high friction disc since the disc’s rotation will help pull/hold the disc in the direction of the spin.  Gyroscopic fade occurs as the disc slows down and causes the disc to fall in an opposite direction from the spin.  Low friction discs will fade earlier than high friction discs since the air friction will help the disc hold the line longer by the greater pull of the rotation in the direction of the spin (and away from the gyroscopic fade).