What is the alternative requirement for a rocket to qualify as a high-power rocket?

A rocket qualifies as a high-power rocket when it has a single motor that demonstrates an average thrust in excess of 80 Newtons. This criterion is essential because the thrust produced directly influences the rocket's performance, including its ability to reach significant altitudes and operate safely under high-power rocketry standards.

In the context of rocketry, ‘average thrust’ is a critical measure that reflects the force being exerted by the motor over the duration of the burn. This capability is vital for ensuring that the rocket can sustain flight and overcome gravitational forces.

The other conditions mentioned in different options, such as the installed impulse of 640 Newton-seconds or achieving a height of 10,000 feet, do not directly capture the operational power and performance parameters defined in high-power rocketry. While these aspects might be relevant in different contexts, they do not specifically delineate the high-power capability as effectively as the thrust measurement does. Additionally, advanced navigational systems, while important for flight control and mission success, do not pertain to the classification of a rocket as high-power based on thrust criteria. Thus, the definition centered around thrust is the most representative of high-power rocketry standards.