Follow-up error: error which is caused by the delay between the existence of a value to be sensed and the availability of the corresponding signal or data stream at the output of the system. This error is e.g. the difference between the real heading of turning vessel and the available information at the output of the system. The follow-up error disappears when the system is static.
Source: IMO Resolution MSC.116(73), Recommendation on Performance Standards for Marine Transmitting Heading Devices (THDs), 1 December 2000, International Maritime Organization. Regulatory Guidance