Which of the following is not a category of high-power rocketry?

High-power rocketry is categorized based on the power output and the level of danger associated with the rocket's propulsion systems. The categories typically include different classes of rockets that refer to their size, weight, and the amount of thrust they generate.

The designation of a model rocket is separate from high-power rocketry. Model rockets are generally classified under lower-power categories and are defined by specific limitations on weight and motor size to ensure safety and simplicity for hobbyists and beginners. They are designed to be launched by amateurs and do not involve the complexities associated with high-power rocketry.

In contrast, Class 1, Class 2, and Class 3 rockets are recognized within high-power rocketry guidelines, indicating progressively higher levels of performance, thrust, and complexity. These classifications are also part of the regulations set forth by governing bodies such as the National Association of Rocketry (NAR) and Tripoli Rocketry Association.

Thus, the correct response identifies a category that does not belong to high-power rocketry while the other options represent recognized classifications within that domain.