What are those four numbers about?
Frequently you may see a series of four numbers on a disc or in the description. They sometimes look like this: [5/4/-1/2]. What do they mean?
Innova Discs was the first to start utilizing four numbers to help explain what you could expect a disc to fly like. These numbers are meant to be a guide only as they will change based on the player's throwing speed, the various plastic types, age of a disc, weather...the list goes on. These numbers give you a starting point to understand. Be aware though, that they are not standardized across manufacturers.
"The Innova Flight Ratings System was designed as a way to describe a discs intended flight. Flight Ratings are broken into four main categories: Speed, Glide, Turn, & Fade. These characteristics can be used to rate various aspects of each disc’s flight. Each disc has a distinct "personality"; the flight path that makes that disc unique. Flight Ratings can be used to compare Innova golf discs to each other. Other companies have adopted a similar system, but it’s important to note that flight ratings shouldn’t be used to compare discs between brands since each company rates discs differently. We have over 90 disc models to satisfy a wide range of players and throwing techniques. To learn more about what each of these characteristics mean, refer to the descriptions below. Flight Ratings are based on right hand backhand (RHBH) throws."
The first number when listed as [1,2,3,4] or the top left number when in a square box is the SPEED.
SPEED 1 TO 14
Speed is the rate at which a disc can travel through the air. Speed 14 Distance Drivers are the fastest, having the PDGA maximum legal wing width. Faster discs cut into the wind with less effort and are best when throwing up wind. Slower discs take more power to throw upwind, but they’re easier to throw more accurately and may actually go farther downwind. High speed discs are not recommended for beginners as they require more power to fly properly.
The second number when listed as [1,2,3,4] or the top right number when in a square box is the GLIDE.
GLIDE 1 TO 7
Glide describes the discs ability to maintain loft during flight. Discs with more glide are best for new players, and for producing maximum distance. Beginners wanting more distance should choose discs with more glide. Discs with less glide are more accurate in high wind situations.
The third number when listed as [1,2,3,4] or the bottom left number when in a square box is the TURN.
TURN +1 TO -5
High Speed Turn is the tendency of a disc to turn over or bank to the right (for RHBH throws) during the initial part of the flight. A disc with a +1 rating is most resistant to turning over, while a -5 rating will turn the most. Discs rated -3 to -5 make good roller discs. Discs with less turn are more accurate in the wind. Discs with more turn are easier to throw for beginners.
The fourth number when listed as [1,2,3,4] or the bottom right number when in a square box is the FADE.
FADE 0 TO 5
Low Speed Fade is the discs tendency to hook left (for RHBH throws) at the end of the flight. Fade is rated from 0 to 5. A disc rated 0 will finish straightest, while a disc rated 5 will hook hard at the end of the flight. High fade discs are usually used for Spike and Skip shots.