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    Re: Wind Velocity from Three Drifts
    From: David Pike
    Date: 2021 Mar 8, 13:04 -0800

    Gary Lapook you wrote: The standard method to mesure the three heading drifts for U.S. Navy navigiators ws to take a drift on the on course heading, Turn 60 degrees and hold that heading for 2 minutes while taking a drift. and then turn 120 degrees the other way (60 degrees on the other side of the on course heading) for 2 minutes. Then turn 60 degrees back onto the on course heading. 

    A 60-degree dogleg was a standard method of losing time without slowing down, but Chichester couldn’t afford to throw fuel away.  At 60kts doing nothing for four minutes would take him 4nm.  30 degrees right, 60 left, 30 right would still take him 3.44 miles along course.  60 right, 120 left, 60 right would only take him 2nm along course.  

    Have you any idea what the tiny lines at 90 degrees to Chichester's celestial LOPs are?  At first, I thought they might be a handy scale that he could set his dividers against and then swivel them through 90 degrees to plot an intercept, but they're by no means equidistant.  Now I think it's just hachuring to highlight them.  

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