These are the official rules for all UWL races. Every UWL race director, race, and racer must adhere to these specific rules at all times. Exceptions are made only for small, local races where the race director feels they can be more lenient for the sake of making the spec more accessible to the participating pilots. Please check back frequently or join the Underground Whoop League (UWL) Facebook group to get updates as fast as possible.

The Spec

-Motors must be from the approved motors list found here.

-RPM Limiter correctly configured on your quad. Please make sure your flight controller supports the RPM Limiter. Find more info here.

-Gemfan 1610 40mm biblades (be sure to get the correct propeller for your motor shaft).

-75mm frame from the approved frame list with no excessive modifications. Further information on allowed modifications here.

-LEDs on your build. Exact rules can be found here.

-All up weight (battery included) must be between 40 and 45g.

-1s 450mah battery. Max starting voltage of 4.35v.

-4x motors in an X4 (aka "Quad X" in Betaflight) configuration. This is the standard configuration. You'll know if you're breaking this rule.


Probation rules are rules that are officially part of the spec and treated as such. The difference is that these rules have not yet had extensive testing, and are therefore more subject to change than other rules. You can think of these rules as an addendum to the core spec rules that may eventually become part of the core spec. However, these rules are still being tested and somewhat likely to change. If you are not interested in frequently updating your build to meet spec, these are rules you might want to stay away from when possible.

The Rules

-The BetaFPV Meteor75 Air frame is allowed in the spec

-Any build utilizing 90FPS HDZero cameras must be a minimum of 41g AUW. Analog, Walksnail, and normal 60FPS HDZero builds are unaffected by this rule.

-ESCs must be running BlueJay 0.16 or newer firmware. JESC, JazzMaverick, and BLHeli_32 are no longer allowed.


In additional to following the previous spec requirements, there are additional rules that will be enforced at most UWL races, including official league races. It is recommended that every race director follow and enforce these rules at their races, however, since these rules are less "spec" specific and more "race" specific, we believe that these rules should be left to the race director's discretion, who holds the responsibility for running the best races possible.

The Rules

-The pilot must have a VTX with a 25mw setting and have their VTX set to 25mw. External VTX Recommended.

-The pilot may not use copper wire monopole antennas for their vtx, such as those that come on Happymodel Diamond and Crazybee Lite flight controllers. Dipoles or circular polarized antennas are recommended.

-Analog and HDZero video systems only. In some cases, a race director may opt to also allow Walksnail.

-Gates should be roughly 28"-35" in diameter. Official UWL spec is 30".