Russian Experimental Nuclear Warheads Were Deployed in Parallel

It appears that we have an answer to the question of what kind of "experimental warheads" were tested in the September 12 Yars launch. And a confirmation of a guess made on Twitter by @artjomh shortly after the test. The image above is from that post - it's from a textbook they use at the Bauman University. According to The Diplomat's Ankit Panda, Russia tested "an independent post-boost vehicle (IPBV) configuration for a three-warhead version [of the Yars ICBM]." The Bauman textbook calls it "an RV with independent (parallel) deployment." As can be seen from the image, each RV is sitting on top of its own mini-bus, which is different from a more common configuration, when one bus deploys RVs one after another.

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