 The UH-72A replaced the TH-6B Cayuse as the prime training aircraft for the test pilot school's helicopter curriculum.By March 2010, the Lakota entered service in Puerto Rico, Kwajalein Atoll, and the US Army's missile test range in Germany.On 20 December 2010, a UH-72A assigned to the Puerto Rico Army National Guard became the first UH-72A to experience a fatal accident.