What restriction does Article 671 impose regarding replacing a vessel?

Article 671 places a significant restriction on the ability of a vessel's owner to replace the ship under a charter agreement. Specifically, it emphasizes that the owner is required to obtain the consent of the charterers before proceeding with any replacement of the vessel. This consent requirement typically serves to protect the interests of the charterers, ensuring that they have a say in the suitability and availability of the replacement vessel.

This restriction is crucial in maritime law and contracts as it maintains the agreed-upon terms and conditions of the charter, preventing unilateral decisions by the owner that could disrupt the charterers' operations or expectations. By promoting communication and mutual agreement between the parties involved, Article 671 emphasizes the importance of collaboration in maritime contracts, where the risks and responsibilities can significantly impact both the owner's and the charterer's interests.