A test facility was developed for the experimental investigation of the large spring-supported thrust bearings used in hydroelectric generators. The test bearing had an outer diameter of 1.168 m, thus making it large enough to simulate most of the features of the thrust bearings in the field, yet small enough to be placed cönveniently in an engineering laboratory. Instrumentation included a distribution of thermocouples and pressure taps along with displacement probes of eddy current type that were located in the rotor to measure oil film thickness. A detailed description of the test facility was provided along with some representative results and a description of some experimental difficulties. A survey of the relevant literature published in the past 40 years suggested that this apparatus was unique in its ability to study relatively large spring-supported thrust bearings in the laboratory.Presented as a Society of Tribologists and Lubrication Engineers paper at the World Tribology Congress in London, United Kingdom, September 8–12, 1997