Figure F32. Plot of the results from three attempts to unlatch the Motion Decoupled Hydraulic Delivery System (MDHDS) during Deployment 1, Site U1402. All three attempts were unsuccessful. We subsequently interpreted that the pressure was raised enough to shear the shear pins, but the pressure was not subsequently reduced enough to allow the spring to expand within the MDHDS latch. As discussed in the text, the standpipe pressure had to drop to <0 in order for the spring to expand against the hydrostatic pressure within the drill string.
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