The navy plays an important role in providing humanitarian relief in times of natural disasters, including floods, cyclones and tsunamis. In the aftermath of the 2004 Indian Ocean earthquake and tsunami, the Indian Navy launched massive disaster relief operations to help affected Indian states as well as Maldives, Sri Lanka and Indonesia. Over 27 ships, dozens of helicopters, at least six fixed-wing aircraft and over 5000 personnel of the navy were deployed in relief operations. These included Operation Madad in Andhra Pradesh and Tamil Nadu, "Operation Sea Waves" in the Andaman and Nicobar Islands, "Operation Castor" in Maldives, "Operation Rainbow" in Sri Lanka and "Operation Gambhir" in Indonesia. Gambhir, carried out following the 2004 Indian Ocean tsunami, was one of the largest and fastest force mobilisations that the Indian Navy has undertaken. Indian naval rescue vessels and teams reached neighbouring countries less than 12 hours from the time that the tsunami hit. Lessons from the response led to decision to enhance amphibious force capabilities, including the acquisition of landing platform docks such as , as well as smaller amphibious vessels.