This paper discusses SEE effects in an architecture based on commercial-off-the-shelf multicore processors for consolidating mixed criticalities applications in single board computers for space applications. This paper builds on previously proposed system-level architectures for mixed-criticality applications, describing them both for convenience together with the previous validation results. The paper proposes a case study on a real space application. Based on reliability and availability requirements of a European Space Agency mission, the paper shows how the proposed solutions can meet availability requirements in two different radiation environments.