  HISTORY
 CL1044/85--USPS INVESTIGATION, EVIDENCE OF THE PRESENCE OF THE OBSTRUCTION WAS OOBTAINED WHEN A SLOOP WITH A 4.5 FT. DRAFT STRUCK IT WHILE UNDER SAIL AT 5 KNOTS ON A NORTHERLY COURSE.  THE KEEL STRUCK FIRST FOLLOWED BY THE RUDDER.  THE IMPACT