Recent Advancements in Solid State Memories have resulted in packing several Giga Bytes (GB) of memory into tiny postage stamp size Memory Cards. Of late, Secure Digital (SD) cards have become a de-facto standard for all portable handheld devices. They have found growing presence in almost all embedded applications, where huge volumes of data need to be handled and stored. For the very same reason SD cards are being widely used in space applications also. Using these SD Cards in space applications requires robust radiation hardened SD cards and Highly Reliable Fault Tolerant File Systems to handle them. The present work is focused on developing a Highly Reliable Fault Tolerant SD card based FAT16 File System for space applications.