EASA has replaced the traditional fixed-type and level qualification for Flight Simulation Training Devices with a capability-based system centered on the FSTD Capability Signature (FCS), fundamentally shifting training from a tool-to-task to a task-to-tool approach. Under Commission Implementing Regulation (EU) 2026/781, which entered into force on 30 April 2026 and becomes fully applicable on 30 April 2028 after a two-year transition, training providers must first define the fidelity levels required for specific tasks before selecting a simulator that matches or exceeds that signature. The new framework quantifies 14 simulation features across aircraft, cueing, and environment groups, enabling qualification of emerging technologies like extended reality and touchscreen interfaces while allowing operators to optimize device selection against precise training objectives rather than legacy categories.