I don't know specifics of this helicopter, but: 1. You can apply patches which turn Linux into RTOS. 2. You can offload RTOS-specific tasks into separate simp

I don't know specifics of this helicopter, but: 1. You can apply patches which turn Linux into RTOS. 2. You can offload RTOS-specific tasks into separate simpler MCUs and use ordinary OS to communicate with them in a more relaxed way.