For anyone else curious about what DAL means:
Design Assurance Levels (DAL)
DAL A describes flight electronics hardware whose failure or malfunction could cause a catastrophic, hazardous, or severe condition that would result in the deaths of everyone aboard the aircraft.
DAL B describes flight electronics hardware whose failure or malfunction could cause a severe or hazardous condition that could involve some loss of life.
DAL C, meanwhile, describes hardware whose failure or malfunction would result in a major flight condition that likely will involve serious injuries.
DAL D describes hardware whose failure or malfunction would result in a condition that causes only a minor non-life-threatening flight condition.
DAL E, finally, describes hardware whose failure or malfunction would have no effect on the aircraft's operational capability or pilot workload.
>https://www.militaryaerospace.com/articles/2016/11/safety-ce...