originally posted July 16th 2019
Correction: BOREI-II class SSBN in Sonar tests
Information surfaced on the Russian internet which confirms that the lead BOREI-II Class ballistic missile submarine, K-549 Knyaz Vladimir, is readying for sonar tests. The frame seen was previously misidentified as a telemetery mast for missile test launches but in fact relates to testing and calibrate the digitally formed passive sonar beams.
The crane-like structure swings out over the bow sonar dome, and is the same device as used on the BOREI-I and some other submarines:
There is also a smaller mast mid-way along the missile deck.
Original artwork - CLICK for HIGH-RESOLUTION image. 
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The image can be geolocated to Severodvinsk where K-549 Knyaz Vladimir is undergoing sea trials. The masts in the background mark the weapons loading pier at 64°34'7.92"N, 39°46'9.30"E. These are on the south side of the harbor so the submarine was outbound when the photograph was taken, in the vicinity of 64°34'34.28"N, 39°46'42.72"E. The date of the photo cannot be ascertained from the metadata but is likely to be very recent.
The submarine will carry the RSM-56 Bulava (3M30 Булава, NATO: SS-N-32) missile which has a range of 5,800 miles (5,040 nm) and can carry 6 x 150 kt MIRVs (Multiple Independent Reentry Vehicles) plus up to 40 decoys.
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