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    B-52 navigator chart from 1969
    From: Paul Hirose
    Date: 2016 Jan 30, 23:11 -0800

    While looking for something unrelated on the Web, I found documents from
    a September 1969 flight of a B-52 (callsign Drab 69) from Guam to
    Fairchild AFB, Washington. The bomber was returning to its home station
    after a deployment to support Operation Arc Light in the Vietnam war.
    Included are the flight plan, charts, and precomputation forms for two
    rounds of celestial sights. Strategic Air Command had its own form for
    that. I wonder why there wasn't a common one for the whole USAF.
    Apparently the standard procedure for B-52s returning to the States was
    to take off from Guam at 1600 local (0600 Z). They would top off with an
    aerial refueling about 90 minutes after takeoff, fly through the night,
    and arrive at Fairchild at 1100 local (1800 Z).
    "B-52D Drab 69 Redeployment Navigator Flight Plan and Charts":
    The two photos labeled "Navigators Station B-52D" are actually show a
    B-52G or H after the vacuum tube bomb-nav system was replaced by the
    Offensive Avionics System in the early 1980s. The upper photo includes
    the same part of the panel shown in a New York Times article I pointed
    out recently:
    That's where the navigator sits. The devices above the left monitor are
    where you insert the tape cartridges that contain the system software
    and mission plan (waypoints, targets, etc.). The tape sockets are
    several inches deep and look bright because they're unpainted aluminum.
    To the right, several publications are stuffed into an unused space.
    They're almost certainly HO 249 and an almanac.
    Below the monitors is the system keyboard, which includes a trackball at
    the lower right corner for controlling the radar crosshair.
    On the side panel are two identical small control panels, each with a
    red switch guard and a gauge. Those control the pumps that keep the
    radar equipment pressurized with dry air. That round bright object below
    and to the left is a pull-out ashtray!
    The RN (= radar navigator, the senior navigator) sits on the left. He
    has the same keyboard as the navigator. The large panel below the left
    monitor selects radar range scale, display format (PPI, off center PPI,
    etc.), and other things.
    Both photos are overexposed and make the black panels look like they've
    faded to gray. Further down the page, the old photo with the round radar
    scope captures the look of the compartment more accurately. I'm not sure
    which model B-52 it depicts. If this is an H, it's way before my time.
    The 5 inch radar scope itself looks familiar, however.
    The RN's scope had twice the diameter and was called the "topo comp"
    (topographical comparator), unfortunately not shown here. It was a
    complex box of optical tricks. A "map match" projector could superimpose
    an image from a 35 mm film strip onto the radar presentation. There was
    a 35 mm radar scope camera too. Both the projector and camera operated
    through the *rear* of the CRT! All this stuff made the topo comp really
    big and heavy. It took two guys to lift.
    Oddly, the old fashioned round radar scopes painted their imagery in
    orange, not green.
    In the lower left of the photo is the joystick to move the radar
    crosshair. It's shared by both men. The nav's table is retracted into
    the console in this view. At upper left are two units which look
    identical, with three oblong windows each. These are the latitude and
    longitude computers. The center window indicates present position with a
    mechanical digital drum counter, similar to an odometer. Above and below
    are counters for the Destination 1 and 2 coordinates, which were set as
    desired by the navigator. Either destination could be selected via a switch.
    The ASB-9A system on the B-52H steered a great circle course until
    within 50 nm of the destination, when it switched to a flat world
    solution. That was hard wired into the system. You could not, for
    instance, select a rhumb line course. I can't remember if the later
    digital system worked the same way.
    The documents and charts on the Web page are full of interesting
    features. The navigator plotted a position every 10 minutes. He
    precomputed the first round of sights for 0910 Z, on AHPHZ, NOOKY (sic),
    and VEGA. Something must have gone wrong on that round. The intercepts
    are large, Ho for Vega is missing, and a vicious expletive is written on
    the form.
    A look at the chart shows another attempt, I think with different
    bodies, 20 minutes later. Results are much better. The precomputation
    form for that round and at least one other round are missing. And on the
    two forms that have been preserved, 80% of the boxes are ignored.
    Also of interest at this site is the page titled "THE NAVIGATOR A FEW
    PHOTOS". Dig that spacious flight deck on the Clipper flying boat. It
    looks like the bridge of a ship!

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