procedures  and  instructions  for  these  trials  in  the shipbuilding  specifications  and  in  special  instructions issued  by  CNO  and  INSURV.  Those  who  may  be involved  with  ship  trials  should  have  a  thorough understanding  of  OPNAV  Instruction  4700.8  and INSURV  Instructions  9080.2,  9080.3,  and  4730.11. Another good reference is  Total Ship Test Program for Ship  Production,  NAVSEA   0900-LP-095-2010. Those  instructions  usually  explain  who  will conduct,  observe,  and  evaluate  the  trials;  who  may attend as unofficial observers and for training; and the procedures required to conduct the trials. This chapter contains information on the following broad types of ship  trials,  some  of  which  include  more  specialized trials: l l l l Contract  trials Special  trials Pre-inactivation  or  pre-overhaul  trials Recommissioning  trials CONTRACT TRIALS New ships and conversions done in naval or private shipyards must undergo ship trials before they are accepted by the Navy. These trials are held to show that the ship is seaworthy and satisfies the operational and technical  criteria  established  by  CNO,  the  SYSCOMs, and the shipbuilding plans and specifications. Contract trials include builder’s trials, acceptance trials, and final contract trials, some of which may be combined under certain conditions. We will explain each of them in the following  pages. When a conventional ship is built or converted in a private shipyard, contractor personnel operate the ship through   the   ship’s   CO   during   the   builder’s   and acceptance trials. SUPSHIP inspection officers observe the trials and evaluate results. The SUPSHIP inspection officer  signs  a  completed  test  or  trial  memorandum  to show acceptance of a satisfactory trial. He then forwards the memorandum with the trial data to the SUPSHIP planning department for approval before it is included in the Ship  Information  Book. A ship constructed or converted in a naval shipyard is  usually  commissioned  several  months  in  advance  of sea trials; therefore, the ship’s force usually carries out dock  and  sea  trials.  The  shipyard’s  ship  superintendent observes  and  evaluates  the  trials  for  the  shipyard commander. For  nuclear  ships,  the  private  contractor  or  naval shipyard conducts dock trials up to the time the reactor is made critical. The officer in charge then conducts the remainder of the dock and sea trials under the overall direction of the shipyard commander or SUPSHIP. During the final weeks of work when the builder is preparing for and conducting ship trials, and before the acceptance  trial,  the  engineer  officer  should  submit  to the  ship’s  CO  lists  of  incomplete  or  unsatisfactory  work and  lists  of  alterations  and  improvements  essential  to  the ship’s mission. The CO should resolve the discrepancies with SUPSHIP or the shipyard commander, and submit requests  for  additional  work  to  NAVSEA  or  INSURV where the shipyard is not responsible for corrections. Builder’s  Trials The builder of a new ship or major conversion must conduct enough dock and sea trials to be reasonably sure the ship will meet the contract requirements just before it undergoes its acceptance trial. In a private shipyard, the contractor conducts these trials on conventional ships and a SUPSHIP representative and the prospective ship’s CO observe them. (See the preceding paragraph for  nuclear  ship  trials.)  For  submarines,  the shipbuilder’s specifications contain requirements for the builder’s trial. DOCK  TRIALS.–   When  the  installation  and testing of all machinery in the engineering spaces are about complete, the builder conducts dock trials to show the SUPSHIP and the prospective engineer officer that the ship is ready for sea trials. When personnel other than the ship’s force conduct dock or sea trials, the engineer  officer  should  arrange  to  have  his  operators observe the operations at the watch stations they will be expected to man after the ship is commissioned. SEA TRIALS.–  The builder’s sea trial should take place as soon as possible after the builder’s dock trial. It should show that the ship is seaworthy and that all its machinery  and  equipment  are  ready  for  the  acceptance trials. A sea trial also shows the proper operation of electronics installations (such as air search radars, sonar, and similar equipments) that require land-free area and deep water to operate properly. The sea trial should include all tests that cannot be performed with the ship moored.  When  the  sea  trial  has  been  completed, SUPSHIP or the shipyard commander notify INSURV of  the  results  and  any  deficiencies  that  cannot  be corrected  before  the  acceptance  trials. 9-20