Upvote:2
The UK is not part of Schengen. Your boyfriend may require a visa to enter the UK, depending on his nationality. If he is South African, he needs a visa. You can check here https://www.gov.uk/check-uk-visa
Upvote:13
Schengen visa does not allow him to enter the UK, nor does the US crew visa (C1/D).
Crewmembers do not need a visa to enter the UK only when they are a part of an operating crew, but when entering as passengers they will need to obtain a UK visa.