To be able to go
astern in the in-
tended direction it
is important to
have the right
initial position.
I
Fig.
8 .
Initial position when going astern.
Fig.
7 .
T h e propeller
of
the A l b i n
25
is
anticlockwise ( l o o k -
ing
f orward seengoing ahead)
The rotating propeller stream
pushes
on
the keel and bottom. I n the lower positions the pro-
peller blades work
in less disturbed water. T h i s adds u p to
a
side
force, which is noticeable when starting from laying still es-
pecially when going astern.
The turning radius
can be influenced
by wind and waves.
When going ahead
the turning radius
it's slightly smaller
when turning
to star-
board than when
turning
to port.
t
When going astern
from lying still the
turning radius
is
very much influ-
enced by the side
force o
peller.
8
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