Human error accounts for a number of collisions at sea; nevertheless, it is widely accepted that vessels are inclined to produce widely varying ranges of radar echo strengths in real sea conditions, in contrast to their ‘true’ anechoic strength, which tends to be minimal for a small and structurally non-reflective craft; even for the calmest possible water conditions.
In this paper experimental results for small craft will be presented and analysed in an exploration of potentially influential parameters in such cases. These results are based on three series of sea trials. Furthermore, an attempt is to be made to portray the inherent, theoretical and/or practical, limitations in the radar detection of small craft in real (estuary) sea conditions.