Saint Helena is more than 2,000 kilometres (1,200 mi) from the nearest major landmass. Prior to the opening of the airport, the island was only reachable by sea, making it one of the most remote populated places on earth, measured as travel time from major cities. Sea journeys used to take five days from Cape Town, with departures once every three weeks. The first consideration of an airport on Saint Helena was made in 1943 by the South African Air Force, which undertook a survey on Prosperous Bay Plain from October 1943 until January 1944. They concluded that, while technically feasible, an airport was not a practical proposition. It was suggested that an airport would extend the United Kingdom's capabilities to carry out airborne missions in the South Atlantic region, such as maritime patrols in accordance with international fishing agreements (e.g., International Commission for the Conservation of Atlantic Tunas), counter-piracy missions along important trade routes, and also airlift operations notably into Southern Africa. According to analysts, the UK government's decision to finally go ahead with the airport, after long delays, seemed to be driven in part by concerns over a continuing tense standoff with Argentina over the Falkland Islands sovereignty dispute. The island is about 3,812 miles (6,135 km) from the Falklands – seven hours and 40 minutes' flight time. But, analysts say that was nevertheless an improvement over the previous state of isolation from the UK for both St Helena and the Falklands. The following possible benefits were also factors in the decision-making process: Air access would allow Saint Helena to develop its tourism sector. The new wharf in Rupert's Bay could allow regularly passing cruise ships to land passengers on the island and bring tourists if sized appropriately. The lack of a protected landing facility represented a limitation on the development of cruise tourism. In unfavourable sea conditions, landing was hazardous and potential revenue was lost as many cruise ships refused to allow passengers to land in such circumstances. In addition, because there was no protected landing facility, many cruise companies did not incorporate St Helena into their itineraries. The sea is roughest in summer, which marks the peak of the cruise season. Medical evacuations to South Africa for treatment of serious cases of illness would be sped up significantly: it may take up to one month until transport to South Africa by RMS St Helena became available. The availability of heavy construction equipment would facilitate alternative energy projects, such as the construction of larger wind turbines, a tidal power plant or a dam with a hydro-power station in one of St Helena's valleys. Limitations in cargo size of the RMS St Helena and the unavailability of a large crane prohibited construction of larger wind turbines. In contrast to the projected benefits, there were concerns that the proposed construction on the Prosperous Bay Plain would be detrimental to the local environment. Specifically, Prosperous Bay Plain was one of the few remaining sites on Saint Helena that held significant ecological diversity. According to a 2004 review by Atkins Management Consultants, the survival of numerous endemic species critically depended on the preservation and protection of the location. It was also an important nesting site for the Saint Helena plover, Saint Helena's national bird, which is listed as vulnerable. Although the St. Helena Leisure Corporation was a major force pushing for the airport's construction, its co-founder Sir Nigel Thompson was a former chairman of the environmental charity Campaign to Protect Rural England. After a long period of rumour and consultation, in March of 2005 the British government announced plans to construct an airport in Saint Helena, expected to be completed by 2010 and funded by the Department for International Development (DfID).