On the day the ferry capsized, the Herald of Free Enterprise was working the route between Dover and the Belgian port of Zeebrugge. This was not its normal route and the linkspan at Zeebrugge had not been designed specifically for the Spirit class vessels: it used a single deck, preventing the simultaneous loading of both E and G decks, and the ramp could not be raised high enough to reach E deck.[2][3] To compensate for this, the vessel's bow ballast tanks were filled.[2] However, the ship's natural trim was not restored after loading.[2] Had the Herald survived, she would have been modified to obviate this procedure.[3]
Before dropping moorings, it was normal practice for the assistant boatswain to close the doors. However, the assistant boatswain, Mark Stanley, had returned to his cabin for a short break after cleaning the car deck upon arrival, and was still asleep when the harbour-stations call sounded and the ship dropped her moorings.[4] The first officer, Leslie Sabel, was required to stay on deck to make sure the doors were closed.[5] Sabel said he thought he saw Stanley approaching. He was seriously injured in the disaster and the court concluded that his evidence was inaccurate.[5] It is believed that under pressure to get to his harbour station on the bridge, he had left G deck with the bow doors open in the expectation that Stanley would arrive shortly.[5] The court also described the attitude of boatswain Terence Ayling, believed to have been the last person on G deck, as most unfortunate.[5] Asked why he did not close the doors given there was no one else there to do it, he said it was not his duty.[5] However the court praised his work in the rescue.[5]
Captain David Lewry assumed that the doors had been closed since he could not see them from the wheelhouse owing to the ship's design, and had no indicator lights in the wheelhouse