Day-to-day airline operations are frequently disrupted by events such as adverse weather, forcing Operations Control to reactively revise the tail assignment. In the literature, robust tail assignment is predominantly studied as absorption robustness, formulated as distributing slack time across the schedule, while robustness through recoverability, the ease with which a disrupted assignment can be repaired, remains understudied. Moreover, existing formulations rarely incorporate maintenance activities beyond standard A checks. This paper addresses whether tail assignments can be made proactively robust in both dimensions simultaneously, proposing a maintenance aware framework that optimizes two complementary objectives: survivability, capturing absorption, and flexibility, capturing recovery potential. The framework is applied to operational data from a large European airline and solved via two methods: an exact Mixed Integer Linear Program and an Adaptive Large Neighborhood Search heuristic with an exact column generation repair operator. The results show that the exact method produces results that are of higher quality in terms of both objectives compared to the heuristic with exact repair, with the gap remaining 4.3% on survivability and 2.6% on flexibility. Hypothesis testing further shows that the two objectives are monotonically related rather than conflicting. These results demonstrate that robust tail assignment can be integrated with non A check maintenance while jointly improving absorption and recovery robustness, offering Operations Control support to move from reactive recovery toward proactive resilience. ... Read more