RE: SQUAT

[Day.John@fin.gc.ca]

Arthur - I think that helps explain the IRS 'squat' - the pavement around
the rear tires of a TR6 and ancestors (4A/250) must actually be lower than
the surrounding pavement when you hit the throttle!
And here I was all this time thinking it was just a sh***y suspension!
Thanks! JD

        -----Original Message-----
        From:   Arthur H. Smith [SMTP:arthurhsmith@compuserve.com]
        Sent:   June 18, 1999 1:52 PM
        To:     triumphs; SPITFIRES
        Subject:        SQUAT



        Last night I watched a program about the investigation into when
the QE ll
        ran aground off Marthas Vineyard. The Captain and pilot both
followed
        proper procedure and the only thing left was the charts showing the
depth
        at 39 feet. The QE ll has a draft of 32 feet so there should have
been
        adequate clearance. At first it was thought the charts could be
wrong so
        NOAA redid the depth sounding and found a few spots a little less
than 39
        feet in depth.

        The final finding was, as a ship moves through the water the force
of the
        water moving under the ship creates a hole around the ship in the
water and
        the ship actual sinks. While the water level along the water line
stays the
        same the depression at the water line is closer to the bottom. This
        phenomenon is called "squat," so as a ship moves it squats down in
the
        water. The full extent of the effect was not totally understood so
at 25
        knots the QE ll sank 8 feet and the 7 feet of clearance disappeared.
Hence
        it ran aground in water that was 39 feet deep.

        It ended with the announcer saying that after 20 years experience
the
        captain of the QE ll didn't know "squat."