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    Re: Daytime Venus Rising Dip Short
    From: Gary LaPook
    Date: 2012 May 6, 11:58 -0700
    I have also taken shots with the Kollsman in a C-130 but most of the inflight shots were in much smaller planes with hand held sextants, mostly the A-10.
    A group of us took some sights in a Cessna about two years ago and everyone noticed how much the bubble moves around in flight compared when a bubble sextant is use on the ground. Look at these prior posts about those flights:

    http://www.fer3.com/arc/sort2.aspx?y=201001su&y2=201001&author=&subject=Cessna%20CN

    http://www.fer3.com/arc/sort2.aspx?y=201001su&y2=201001&author=&subject=CN%20aboard

    gl
    --- On Sun, 5/6/12, Robert Eno <enoid{at}northwestel.net> wrote:

    From: Robert Eno <enoid{at}northwestel.net>
    Subject: [NavList] Re: Daytime Venus Rising Dip Short
    To: NavList@fer3.com, NavList@fer3.com
    Date: Sunday, May 6, 2012, 7:52 AM

    From what I understand, two vertical wires are all that is needed because
    with a spherical bubble chamber, a slight fore and aft tilting of the
    sextant has no appreciable effect on the accuracy of the sight. A lateral
    (side to side) tilt does have significant negative consequences in the
    accuracy of the sight.

    I can support this contention based on my own observations taken with my
    MkIXA sextants and with the pre-1970's era C.Plath bubble attachment
    (notwithstanding that the C.Plath has both vertical and horizontal wire).

    I have had the pleasure of using a Kollsman Periscopic sextant in a C-130.
    Let's just say it is not as easy as it looks!

    Robert

    ----- Original Message -----
    From: "Alexandre E Eremenko" <eremenko---.edu>
    To: <NavList@fer3.com>
    Sent: Sunday, May 06, 2012 10:08 AM
    Subject: [NavList] Re: Daytime Venus Rising Dip Short


    >
    > Gary,
    >
    >> They are only in the Kollsman instruments.
    >
    > In MkIXA as well. Two vertical wires helping you to keep the
    > bubble near the center.
    >
    >
    > Alex.
    >
    >
    >
    >
    > __________ Information from ESET Smart Security, version of virus
    > signature database 7113 (20120505) __________
    >
    > The message was checked by ESET Smart Security.
    >
    > http://www.eset.com
    >
    >
    >


    __________ Information from ESET Smart Security, version of virus signature database 7113 (20120505) __________

    The message was checked by ESET Smart Security.

    http://www.eset.com




       
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