ALTEN Global has developed its own RTOS called OASYS that is used in several embedded applications on Airborne Systems. The RTOS is A653 compliant and is ported on multiple platforms including ARM and PowerPC.
OASYS implements the complete ARINC 653 Part 1 Basic Services and supports Space & Time Partitioning concepts. It is used as the Operating System for an airborne early warning system and Control & Display unit for rotorcraft. These systems have gone through rigorous DO-178B compliance checks and is certified by CEMILAC for use in Airborne Systems.