Page 147 - test2

pod showed that, in its as‐received condition, the 27‐volt batteries on the blue
348
pod did not have enough power to complete the AMF sequence.

Function testing of the yellow pod yielded inconsistent results due to one
349
of the solenoids (solenoid 103Y). A solenoid valve, in response to an electrical
signal, opens or closes a hydraulic circuit to function BOP stack components.
This functioning allows hydraulic fluid to close the BSR.

I. Evaluation of Other Possible Failures

During the ROV interventions, there were reports of leaks in various
hydraulic circuits. DNV found that “the evidence indicates the reported leaks in
the hydraulic circuits were not a contributor to the Blind Shear Rams being
unable to close completely and seal the well.”
350

DNV reviewed various modifications made to the control logic or to the
BOP stack prior to the blowout. DNV found that “there is no evidence these
modifications were a factor in the ability of the Blind Shear Rams being able to
close fully and seal the well.”
351

DNV tested the performance of solenoid 103Y that was removed from the
yellow pod and obtained inconsistent results. DNV observed that, when both
coils within the solenoid were activated (which is what should happen if the
solenoid was activated by the AMF circuits), the solenoid functioned properly.
But when only one of the coils was activated, the solenoid failed to function
properly. DNV posited two theories for why this occurred. First, the solenoid
was removed in May 2010 but was not tested until March 2011. DNV found that
it was possible that seawater deposits or hydraulic fluid build‐up was the cause
of the inconsistent results. Second, it was possible that the solenoid had a
manufacturing defect. DNV stated that it “did not identify any other issues or
evidence that manufacturing defects of one form or another contributed to the
Blind Shear Rams not closing completely and sealing the well.”
352

348 However, the Panel found that this was not conclusive because the blue pod may have
performed the AMF sequence some time after the loss of well control, which may have caused its
as‐received condition.
349 DNV Report, Vo1. 1, at 171‐72.
350 Id. at 171.
351 Id. at 172
352 Id.

142