Mr Botibol advanced slowly to a position at the rail about twenty yards away from the woman. She wasn’t looking at him now. So much the better. He didn’t want her watching him as he jumped off. So long as no one was watching, he would be able to say afterwards that he had slipped and fallen by accident. He peered over the side of the ship.
(Source "Dip in the Pool", by Roald Dahl.
Just one question regarding the excerpt from Dahl's short story. Why is the past tense used in the clause as he jumped off? The story is told in the past tense. But the thoughts about the events of the protagonist (the planning jump off the ship) are from his point of view set in the future so I would await "as he would jump off".