Spire

Spire is a military class service droid in use by Earthfleet to fill gaps in their ranks due to personnel shortages. He begins his life aboard the Appalachia serving as her chief engineer, but eventually becomes captain of his own ship, and later the captain of the Prometheus. Despite being an android, he is a very astute and skilled officer, and captain, and proves his mental many times over his many, many decades of faithful service. He even remains as an integral part of the fleet long after other droids like himself are retired from service.