It is being reported that the Navy has begun evaluating the feasibility of adding the Virginia Payload Module (VPM) to boats in the forecast Block IV procurement.
The reason being given is that early addition of VPM equipped boats would mitigate the loss of firepower projected to be lost as the SSGN Ohio boats begin retiring in 2020.
Block V, VPM equipped, Virginia-class boats aren't forecast to begin construction until 2019. So, the first Block V boat wouldn't enter service until years after the first Ohio SSGN was retired.
While it isn't mentioned, it's not outlandish to think that this early procurement might also have to do with getting some VPMs into the fleet before the Ohio Replacement Program starts eating away at construction funds.
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