Swerve - I know where Vauxhall is and the heliport.
Read this?
"What I saw this morning was not good: a helicopter flying at about 500ft eastbound along the Thames helicopter route.
As it was just passing over Chelsea Bridge" from
Visibility must have been zero, or close to it... The helicopter flew straight into dense fog. As a former pilot, this struck me as peculiar, to put it mildly' - Comment - Voices - The Independent