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This story is about how the first SubRoc missile fired in the Atlantic came very near reversing course after launch, and proceeding in the opposite direction away from the intended target. That this did not happen was due to a fortunate event occurring in the hours before the launch, and a disciplined and inspired performance by the submarine’s fire control technicians led by Chief Fire Controlman William A. Seimer.

USS DACE (SSN 607) was designated in 1965 to be the lead SubRoc boat in the Atlantic Fleet. USS PLUNGER (SSN 595) a Pacific Fleet SSN, had completed the operational evaluation firings earlier. In 1966, shipboard preparations for the SubRoc capability were completed, and a test missile was loaded aboard. DACE, commanded by Commander William J. Cowhill, sailed out of New London for Fort Lauderdale, enroute to the AUTEC firing range for the launch.

At Fort Lauderdale, mail call brought a package from the Naval Ordnance Laboratory White Oak. with a request for the submarine to install the enclosed instrumentation. While somewhat dismayed at the absence of a NOL engineer or technician to assist in the hook up, the package was opened up by the fire controlmen. The instrumentation consisted of a bearing circle synchro receiver about the size of a dinner plate, with five attached leads. The instructions were straight forward, calling for the standard synchro transmission line-up, SI to SI, S2 to S2, S3 to S3, R l to R l, and R2 to R2. The leads were attached to the submarine fire control system, across the wiring that sends the firing bearing to the SubRoc missile. The bearing circle worked perfectly, except that the displayed bearing was 180° different from the bearing indicated on the SubRoc simulator (this was a small suitcase that plugged into the launch panel in the Torpedo Room) that had been used for all fire control system testing involving SubRoc to date!

While not obvious at first, it became apparent that there was a wiring reversal in the fire control system, and probably in the SubRoc simulator as well. As this point, Chief Siemer and his men, aided by a Librascope field engineer, started through the fire control system lead-by-lead, trying to find the reversal. One of the immediate trouble-shooting challenges was how to detennine whether the signals on the circuits were in, or out of phase. Through sheer genius, one of the trouble-shooters came up with the idea of comparing J.,issajous figures on an oscilloscope, perhaps as taught at FT “A” or “B” school?

DACE, with VADM V. L. Lowrance, COMSUBLANT, embarked, along with an observer from one of the New Mexico AEC laboratories, got underway for the AUTEC range. Within a few hours of launch, Chief Siemer and his people had located and made the necessary wiring changes, and were satisfied that everything worked.

The test missile was made ready and loaded for launch. The missile was fired at the prescribed time, with Admiral Lowrance watching on Number One periscope. He said something like “Look at that son-of-a-b …. go!”

The missile proceeded down range as intended. There is no doubt that Chief Siemer and company deserved all the credit for this shot being a success. Thanks are also due to the unknown person at NOL White Oak, who thought that reading and recording the firing bearing on a NOL bearing circle, would be useful for post flight analysis

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