randomTOTEN Posted July 12, 2022 Posted July 12, 2022 The dial indicator on the KM-2 (top of instrument) acts as an independent gyro, when I don't believe it should. KM-2 takes heading information from the Induction system (flux gate compass) and combines it with a correction value called variation/declination to output a "true" heading value which can be used to align the gyro system. Or any other declination value... allowing for "grid" navigation. My understanding is that the face of the KM-2 then has the purpose of informing the crew what alignment signal is correcting the gyro orientation. There should only be 2 modes of operation. ZK, in which the declination setting is the only value (flux value excluded) and so the indicator should always equal the declination value set at the bottom of KM2, without exception. The other option is mode MK, in which MH(magnetic heading)+/-MV(magnetic variation)=TH(true heading). In the supplied track, I enter various values of declination, align the gyros using both ZK and MK, and make a series of turns. At the end, the helicopter has a MH of 270, variation value of 0 set using mode ZK, yet the KM2 indicator shows 090. This is because as I turn the helicopter, the KM2 indicator rotates like a gyro, despite the flux gate being removed from the equation. It should have no idea that anything is turning. The indicator will then "slave" when pressing the Greben Match button. But what's it being matched to? Only the value entered at the bottom of the instrument. It should have been indicating that the whole time. This is a difficult thing to describe, I understand there will be some confusion on this. But it operates very strangely right now, and isn't agreeing with the tests I can find online. Thanks. KM2 acts like gyro.trk
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