A historical review of ship model testing in open waters

Specific features of model testing on hydrodynamic ship behaviour will be discussed, in particular with respect to extreme motions in a natural seaway of open waters. Ship model features described are model scale, water tightness, auto - pilot and remote control, data recording, testing procedures and choice of model situations. Wave gauges supported by buoys allowed measuring seaway. Logistics of open water model testing is compared with new procedures in water tanks generating seaway extremes. A short glimpse is given concerning results found with respect to ship capsizing in random seas. Some photographs allow a lively remembrance of early activities in model runs on a lake many decades ago.