GR translation: Smiling passengers halfway down

[Mike Jing]

V459.39-41, P467.22-25   The boat comes in to the quay, the crew lower an
access ladder. Smiling passengers halfway down are already stretching out
gloved and ringed hands to Margherita.

What does "halfway down" refer to here? The passengers apparently are not
getting off the boat, so they shouldn't be halfway down the ladder, and the
ladder would't be able to accommodate multiple passengers anyway.