Twelve USMC F4U-1s arrived at Henderson Field (Guadalcanal) on 12 February 1943. The U.S. Navy did not get into combat with the type until September 1943. The work done by the Royal Navy's FAA meant those models qualified the type for U.S. carrier operations first. The U.S. Navy finally accepted the F4U for shipboard operations in April 1944, after the longer oleo strut was fitted, which eliminated the tendency to bounce. The first US Corsair unit to be based effectively on a carrier was the pioneer USMC squadron VMF-124, which joined "Essex" in December 1944. They were accompanied by VMF-213. The increasing need for fighter protection against "kamikaze" attacks resulted in more Corsair units being moved to carriers.