A sextant is an instrument used
to measure the angle between
any two visible objects. Its
primary use is to determine the
angle between a celestial object
and the horizon which is known
as the object's altitude. Making
this measurement is known as
sighting the object, shooting the
object, or taking a sight and it is
an essential part of celestial
navigation. The angle, and the
time when it was measured, can
be used to calculate a position
line on a nautical or aeronautical
North- continuous flashing , south- 6 flashing, east- 3 flashings and west- 9 flashings
south 6+1long flash
3 distinct strokes
rapid ringing of bell 5 secs
3 distinct strokes
if 100m or more
gong shall be sounded 5 secs
additionally . . - 'U' you are running into danger.
brendon n kamlesh
on radar it must have a constant speed .and by checking the aspect..
Chart Datum is an arbitrary plane below which low water tide seldom falls. It is a datum to which sounding on a published hydrographic chart are reduced. All the bathymetric contours are referred to this datum. The tidal predictions and tidal levels given in the tide tables are also given with relation to the same datum. Chart datum in India had been fixed at Indian Spring Low Water Mark (ISLW) during nineteenth century. For this, sufficiently long tidal observations had been made at various locations. During the Spring tide, low water mark had been measured and fixed as chart datum at this location
All indian charts are based on Everest datum. Check MS notice 1/2004
two all around red light placed where it can best be seen, if making way through the water in addition to red light side light and stern light.
there will be two red liht plus all navigatinal light
2 all round red lights in vertical line, and if making way in addition, sidelights n sternlight
AS NUC AND RAM ARE CONSIDERED HAMPERED VESSEL,SINCE BOTH ARE AT RISK OF COLLISION ,BOTH VESSEL SHOULD REDUCE HER SPEED, STOP AND REVERSE HER PROPULSION BUT IT MAY BE RELAXED TO RAM DUE HER DISPLACEMENT.