ER stands for Extended Range These aircraft types that is identified by 'ER' are aircraft models that is enhanced for better efficiency at long range flights than its counterpart aircraft of the same model. Source(s): Aerospace Engineer - Aviation Enthusiast
Actually Dusty.... The leeward side extends all the way to Koko Head (encompasssing Pearl Harbor, Honolulu to Hawaii Kai). By definition. Windward is the side of an island where the predominant wind travels from the sea onto the island. Leeward is the side of an island where the predominant wind travels from the interior of the island to the sea. In practice on Oahu.
Sometimes the synonyms downwind (same as leeward) and upwind (same as windward) are used instead. They are also widely used on the islands of Hawaii to give directions or describe locations. The tropics on earth have pretty constant east-ish winds, caused by solar heating and the rotation of the earth.