Tests by Nasa JPL, on the large GL4 systems they are using to cool the Deep Space Network optical communication receivers, have demonstrated that our 1K modules operate satisfactorily even when orientated at 90 degrees to the vertical. This result is somewhat surprising given that the modules rely on gravity to ensure that their Helium charge, when liquified, collects in the cold head of the module. However we have long thought it likely that provided the initial cooldown is carried out in near-vertical orientation, tilting the module during running would not necessarily impair its function. It’s really pleasing to get this confirmation from JPL that both running temperature and run time appear unaffected by tilting the module, as many applications require some freedom of orientation.

Read NASA/JPL’s report on these experiments here