TechDisc is an innovative new tool to "Know Your Throw" with hardware and software designed by disc golfers to accelerate every athlete's progression in the sport. 

Sensors in the center of a golf disc measure the forces and angles put on a disc. The data is stored on the web app that determines the throw type and calculates 6 throw metrics and a simulated flight.

These metrics are Speed, Spin, Nose Angle, Hyzer Angle, Launch Angle, and Wobble. This article is intended to show more detailed information on these metrics and how they impact disc flight.  

Understanding these metrics are important when training or playing a round on the course, as they will create heightened awareness of your disc's flight patterns and allow you to recognize and focus on areas of improvement.

Note: Flight numbers and baseline metrics that were used in the simulations below are shown at the end of this article. Follow along with this simulated throw here to see how each metric affects the flight path.

Speed

TechDisc measures Speed in MPH or KMH to within + 2, - 1 MPH accuracy compared to conventional radar by using an array of accelerometers, which are devices that measure acceleration or motion.

Why Speed is Important:

• In general, more speed = more distance (assuming identical throws) 

• Higher Speed affects a disc similarly to a faster headwind, creating a more understable flight, on average, as speed increases.  

Spin

TechDisc provides the first accessible accurate & reliable method of measuring the RPM of a disc in-flight.

Why Spin is Important:

• In general, Spin allows a disc to remain straighter in-flight by resisting turn and fade.

  • This can increase distance because spin can give “more air hangtime” before fading (dependent on disc speed and stability rating)

• Higher Spin stabilization creates a more stable flight, on average.

• Advance Ratio is another TechDisc metric that shows the relationship between spin and speed for a given throw, and is a good measure for optimal spin rate.

  • An Advance Ratio of 50% is a good target for a backhand throw and an advance ratio of 30% is a good target for a forehand throw.

  • The body mechanics involved in a backhand throw creates more spin than forehand throws, on average.  

  • A disc rolling on the ground is defined to have an Advance Ratio of 100%.  In some sense it is spinning the same rate it is moving forward.  More precisely, the Advance Ratio is defined to be the spin times the disc radius over the speed.

  • See more about how advance ratio is calculated here

Nose Angle

Positive vs. Negative Nose Angle   *Photo Credit:  Ultiworld Disc Golf

Also known as “Angle of Attack”, Nose Angle measures the back-to-front pitch angle of the disc in relation to oncoming air, or put simply, the angle relative to the flight path of the disc.

This is distinct from Launch Angle (described below), which measures the angle of the disc's trajectory in relation to the ground or horizon.  

Why Nose Angle is Important:

• A disc with a positive nose angle (aka “nose-up”) means more of the oncoming air will meet the bottom plate of the disc and will increase lift while also increasing drag (and vice versa for nose-down). 

  1. This means that nose-up discs will have a tendency to travel high and drop more quickly. 

  2. Nose-up discs will also be more affected by headwind and nose-down discs will be more affected by tailwind. 

• The ideal nose angle for a disc appears to be around -2° to -3° for distance throws because of its lift / drag efficiencies.   

  1. Even though a 0° nose angle has the least cross-sectional area and hence the least drag, the dome of the disc provides additional lift when thrown nose-down. 

• The interplay between Nose Angle and Launch Angle is important to consider and can significantly impact flight characteristics. 

Launch Angle

Note:  Both of these simulated discs were thrown with a -2.5° nose angle (nose-down)

Launch Angle is the angle of the disc’s flight compared to the ground or horizon.  In other words, “throwing a disc high” means you are releasing the disc at a positive launch angle.   

A completely “flat” throw would indicate a Launch Angle of 0°.  A negative launch angle means the disc is released on a trajectory pointed towards the ground

Why Launch Angle is Important:

• Ideal Launch Angles depend on the Nose Angle and Speed of the disc.  

  1. For our 60 MPH baseline throw in the TechDisc simulator, the optimal throw for distance is approximately an 8° to 10° Launch Angle combined with a -3° to -5° nose angle.

  2. Ideal Launch Angles tend to decrease as speed increases. 
     
     

 Air Bounce

Negative Launch Angles can still achieve long distances when combined with Positive Nose Angles.  This leads to the disc beginning its flight as what is known as an “air bounce”.  

However, maximum distance will be limited due to the aerodynamic characteristics of nose-up flight.

Hyzer Angle

Hyzer Angle refers to the side-to-side angle of the disc while looking from the thrower's perspective.  Throwing a Hyzer means the outside edge of the disc (away from your body) is closer to the ground on release, and vice versa for Anhyzer.  

Why Hyzer Angle is Important:

• Hyzer angle is the main metric that controls the right and left movement of the disc in flight.  Shaping shots through the woods or creating a maximum distance flight path is dependent on Hyzer angle in combination with the disc's speed, glide and turn.

  • For a right-handed backhand throw (RHBH), a throw with positive Hyzer angle will usually cause a disc to move to the left and finish left after release, depending on the stability of the disc.  

  • If a RHBH throw is released on an Anhyzer angle, the disc will move to the right after release, and could either keep moving right for the remainder of the flight with a sufficiently understable disc, or will straighten and begin fading back to the left with a stable disc. 

Max Distance Throws

Maximum distance throws will usually have an Anhyzer angle for the majority of the flight, and fading to Hyzer towards the end of flight.

This is because a disc will generally take longer to reach the ground on an Anhyzer angle. 

Wobble

Photo Credit:  Ultiworld Disc Golf

"Wobble" refers to the Off-Axis Torque applied to a disc during a throw.  A disc with Wobble will appear to flutter in the air before eventually stabilizing.  

TechDisc's Wobble metric shows the angle of the disc relative to its axis of orientation. 

Why Wobble is Important:

• Wobble introduces turbulence to a throw, inducing drag and a creating a more chaotic, unpredictable flight.  

• Wobble can make discs fly more Understable, especially in a headwind.

• Wobble often corelates with low Spin Rate or low Advance Ratio.   In general, higher Spin will stabilize Wobble earlier in the disc's flight and minimize the effect of wobble on the disc's flight.

Simulator Baseline Metrics in This Article 

Baseline Throw Simulated Disc - All simulated throws in this article are using a 175-gram fairway driver with the following flight numbers: 

Baseline Throw Flight Metrics –  Simulate for yourself here

• Speed: 60.0 MPH

• Nose Angle:  Negative 2.5°

• Hyzer Angle:  10.0°

• Launch Angle:  5.0°

• Spin: 1000 RPM