After a failure in December 2009, further tests were put on hold and a probe was conducted to find out the reasons for the failures. Testing was resumed on 7 October 2010 with a launch from the in the White Sea; the warheads successfully hit their targets at the Kura Test Range in the Russian Far East. Seven launches have been conducted since the probe, all successful. On 28 June 2011, the missile was launched for the first time from its standard carrier, Borei-class submarine , and on 27 August 2011 the first full-range (over ) flight test was conducted. After this successful launch, the start of serial production of Bulava missiles in the same configuration was announced on 28 June 2011. A successful salvo launch on 23 December 2011 concluded the flight test programme. The missile was officially approved for service on 27 December 2011, and was reported to be commissioned aboard "Yuri Dolgorukiy" on 10 January 2013. The missile did however continue to fail in the summer of 2013 and was not operational as of November 2013. The Bulava became operational aboard "Yury Dolgorukiy" as of October 2015. However, recent developments put this in question. In November 2015, the submarine fired two missiles while submerged. One of the missiles self-destructed during the boost phase and the other failed to deliver its warheads to the specified target. After being sent back to the manufacturer, it was determined that the missiles failed due to manufacturing defects.