The guy who's being controlled by the Cybermen and has taken over the Graviton is repeatedly referred to as "Evans", but the name on his shirt reads "Beckett S."
Incorrectly regarded as a goof - Evans knock out Beckett in an earlier scene in the infirmary and puts on Beckett's outer garment that has Beckett's name on it, but they can see Evans' face so know it's him.
After Evans attacks the operator of the Graviton and takes his head covering, he puts it on his own head the wrong way up.
Prop wall swaying when Ben and Jamie ram into the Cyberman making his way out of sick bay.
Wire visible on the spaceship of Cybermen reinforcements as it lands.
A stage hand can be seen in the background moving a telescope as the Doctor talks to Hobson.
Behind the doctor and Hobson when the telescope is in view a stagehands hand can be seen moving the telescope.