Survey Ship Sigma was the saucer used by a small contingent of Daleks sent on a mission to travel through Earth's history and analyse how humans made war so that weaknesses could be found and exploited in future conflicts with the Daleks. They called this mission the Dalek Project. A Black Dalek was connected to this ship and acted as the leader of the Dalek Project. This saucer was equipped with new time-drive systems and got caught in a Vortex storm.
It landed in 1908, collided with Survey Ship Delta and its main drive was damaged. It hid underwater on Kent to wait until the First World War began, at which point the Daleks would send a lone drone claiming to be the last of its race to contact Lord Hellcombe. In 1915, the Daleks fired a missile to shoot down a plane piloted by Hellcombe's son, Ralph, and used his remains to create a robotic duplicate of him to convince Lord Hellcombe that the Dalek had saved his son.
Later, as the Dalek Project reached its conclusion, Survey Ship Sigma deployed Aqua-Dalek units to destroy a submarine piloted by the Doctor and his companions. it travelled to France and carried an assault force to help the Proto-Daleks to exterminate all humans to eradicate all evidence of Dalek intervention in 1917. The Eleventh Doctor defeated the Daleks and sent their ship crashing undergound. One hundred years later some archaeologists came across the crashed Dalek Saucer in France after it had crashed and accidentally revived the surviving Daleks inside. The Eleventh Doctor arrived just in time to prevent a disaster and connected the saucer to a power line, overloading the Daleks. He saw this as him dealing with "unfinished business". (COMIC: The Dalek Project)
Behind the scenes Edit
On pages 85 and 101 of The Dalek Project comic, the top of the saucer was coloured blue.