14 CFR § 450.167 - Tracking.
(a) General. During the flight of a launch or reentry vehicle, an operator must measure and record in real time the position and velocity of the vehicle. The system used to track the vehicle must provide data to predict the expected impact locations of all stages and components, and to obtain vehicle performance data for comparison with the pre-flight performance predictions.
(b) Application requirements. An applicant must identify and describe each method or system used to meet the tracking requirements of paragraph (a) of this section.
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