The test liquid was a low viscosity fluorinert FC-72. The properties density, surface tension and viscosity are similar to those of storable propellants, if similarity laws taking into account the channel geometry are applied. Thus the results can be transferred from the model to the original spacecraft. The images of the test channel and the compensation tube were captured by a high resolution camera and transmitted to the ground. Simultaneously, a laser Doppler velocimeter, developed by ZARM, was used to measure the flow-velocity inside the channel. The flight procedure was performed using these video data as well as other numerical data from the setup via telecommand.

The filling of the compensation tube and the test section in the beginning of the experiment was accomplished within 25 seconds. The flow rate was increased in coarse steps from 3.0 to 8.5 ml/s without gas ingestion. The fine approach until the collapse of the free surface at 8.9 ml/s was achieved using steps of 0.05 ml/s. The flow was stabilized again at 8.0 ml/s to measure the velocity profile using the onboard LDV. Finally the length of the test channel was changed from 12 mm to 17.8 mm in fine steps of 0.4 mm. A second collapse could be observed at the end of the mission. The two pictures show a stable, steady flow with 8 ml/s at l = 17.7 mm and an unstable, unsteady flow with a slightly larger channel length.