A Hellenic Seaways Highspeed catamaran carrying 120 passengers was unable to depart from the port of Piraeus on Wednesday 16th September 2026 after a mechanical problem was detected before its 10:00 departure.  The AERO 4 Highspeed vessel was scheduled to sail to the islands of Poros, Hydra and Spetses, with a stop in Ermioni on the Peloponnese coast.  All the passengers were transported to their destinations at the company’s expense, according to the Greek Coast Guard.  The new AERO 4 and 5 Highspeed catamarans were only put into service on the Saronic Gulf routes at the start of the Summer 2026 season.  The two new Hellenic Seaways AERO 4 and 5 Highspeed vessels replaced the aged fleet of four 'Flying Cat' catamarans, that were retired at the end of 2025 after 34 years of service. 

A smaller Hellenic Seaways AERO 2 Highspeed catamaran suffered another mechanical problem before its scheduled departure from the port of Piraeus on Friday 4th September 2026.  The AERO 2 Highspeed vessel was scheduled to sail to the Saronic island of Aegina, carrying 52 passengers, which were transported to their destination by the ship-owning company, Hellenic Seaways.