After a very successful environmental test campaign at the end of last year for the Engineering Qualification Model (EQM) of our ESAIL ADCS I/F unit (Attitude Determination and Control System Interface Unit), our in-house development has taken the next hurdle for ECSS qualification. The SQM (Soldering Qualification Model), after undergoing the same mechanical testing as the EQM, was subject to a thermal cycling campaign which took place in Denmark. The test campaign was compound of 500 thermal cycles at ambient pressure within a temperature range of – 30°C to 70°C and a period of 1.5 hours. Such conditions represent an accelerated lifetime test. After 200 cycles (which are equivalent to the lifetime of the ESAIL mission, 4 years) the unit performances were tested successfully. Then the rest of the cycles were completed to reach full ECSS qualification level for the assembly processes. The test campaign went very smooth and quick, also thanks to the automatic functional test software as another LuxSpace inhouse development. The team is proud to announce that, after the full 500 thermal cycles, there was almost no deviation detectable from the unit’s initial performance. Right now, microsections of the unit components are being analyzed to reach the final step for the ECSS qualification