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by icegreentea2 873 days ago
From https://secwww.jhuapl.edu/techdigest/Content/techdigest/pdf/... it seems that the two control fins are driven off a single shaft/motor - so they are not independent.

The RAM uses single plane tracking - basically imaging that it's only ever steering in pitch. But because it's constantly rolling, "pitch" will sweep over both axes and control to zero.

1 comments

Yeah (and apologies if I get this wrong after 30 years) with a rolling airframe, you can have two fins on the same axis that "wiggle" back and forth at the same frequency as the rotation of the missile. Direction control comes from the phase of the movement, so the fins are pushed in the direction you want to go when it rotates to that point.