Post on 22-Dec-2014
description
Grunt Productions 2007
BLIND PILOTAGEA Brief By Lance Grindley
Definition:Definition:
‘‘The navigation of the ship through The navigation of the ship through restricted waters in low visibility restricted waters in low visibility with little or no recourse to the with little or no recourse to the visual observation of objects outside visual observation of objects outside the ship.’the ship.’
Grunt Productions 2007
BLIND PILOTAGEBLIND PILOTAGE1.1. Navigation and PilotageNavigation and Pilotage
a)a) Primary method: VisualPrimary method: Visualb)b) Secondary method: RadarSecondary method: Radarc)c) Other methods: ‘NAVAIDS’Other methods: ‘NAVAIDS’
2.2. Fundamental Navigational Radar Fundamental Navigational Radar a)a) Stabilised in azimuthStabilised in azimuthb)b) Bearing accuracy ±1°Bearing accuracy ±1°c)c) Range accuracy better than 20 yds (depending on pulse Range accuracy better than 20 yds (depending on pulse
length)length)d)d) Anti-clutter controlsAnti-clutter controlse)e) Range scales (1007)Range scales (1007)
0.5, 0.75, 1.5, 3, 6, 12, 24, 48 miles0.5, 0.75, 1.5, 3, 6, 12, 24, 48 milesf)f) Fitted with: Electronic Blind Pilotage SystemFitted with: Electronic Blind Pilotage System
Grunt Productions 2007
PLANNINGPLANNING
TRACK - Chosen by Master, based on TRACK - Chosen by Master, based on visual plan.visual plan.
SAFE WATER - Delimited by Limiting SAFE WATER - Delimited by Limiting Danger Line (LDL):Danger Line (LDL):
Draught+2m-Height of Tide.Draught+2m-Height of Tide.
Grunt Productions 2007
BLIND PILOTAGEBLIND PILOTAGE
• Where are we in relation to planned Where are we in relation to planned track ?track ?
• How much safe water remains ?How much safe water remains ?
• How far to run to the next course How far to run to the next course alteration ?alteration ?
Grunt Productions 2007
Parallel Indices
2m
Grunt Productions 2007
080(080)
020
(020
)
WO
7.6c
4.0c
5.2c
Grunt Productions 2007
Grunt Productions 2007
080(080)
020
(020
)
WO
7.6c
4.0c
5.2c
NMT 11c
NLT 2c
NMT 13c
NLT 1c
Grunt Productions 2007
Grunt Productions 2007
080(080)
020
(020
)
WO
7.6c
4.0c
5.2c
NMT 11c
NLT 2c
NMT 13c
NLT 1c
6.2c
Grunt Productions 2007
Grunt Productions 2007
Grunt Productions 2007
Grunt Productions 2007
270 (270)
1m
NLT 4c
NL
T 5
c
1.3m
NL
T 3
c
1.4m
Grunt Productions 2007
IN POSITIONIN POSITION
Grunt Productions 2007
Radar Radar ErrorsErrors
Index ErrorsIndex Errors
Grunt Productions 2007
True RangeTrue Range
Displayed Radar Range
Displayed Radar Range
Index ErrorIndex Error
Ie +/- 50 ydsIe +/- 50 yds
Grunt Productions 2007
FINDING THE INDEX FINDING THE INDEX ERROR TWO MARK ERROR TWO MARK
METHODMETHOD
A = True range ± IEA = True range ± IEB = True range ± IEB = True range ± IEC = Charted C = Charted distancedistance
Index error = Index error = C – (A + B)C – (A + B)22
AA BB
CC
Index errorIndex error
Grunt Productions 2007
Three Mark MethodThree Mark Method
Grunt Productions 2007
False EchoFalse Echo
Grunt Productions 2007
Two Ship MethodTwo Ship Method
Compare B to A to find Index Error. IE = B - A = C - 2ACompare B to A to find Index Error. IE = B - A = C - 2A
A(IE)A(IE)
Range (A) between own ship and other incorporates Index Error.Range (A) between own ship and other incorporates Index Error.
C (IE)C (IE)
Range (C) between own ship and false echo also incorporates Index Error.Range (C) between own ship and false echo also incorporates Index Error.
B(No IE)B(No IE)
True Range is therefore C-A which equals B.True Range is therefore C-A which equals B.
Grunt Productions 2007
Radar Radar ErrorsErrors
Index ErrorsIndex Errors Strobe AccuracyStrobe Accuracy
Grunt Productions 2007
Distortion caused by beam width
Direction ofAerial Rotation
A2
A1
B
C
D
Coastline
E
Grunt Productions 2007
Radar Radar ErrorsErrors
Index ErrorsIndex Errors Strobe AccuracyStrobe Accuracy Error introduced by controlsError introduced by controls
Grunt Productions 2007
Grunt Productions 2007
Radar Radar ErrorsErrors
Index ErrorsIndex Errors Strobe AccuracyStrobe Accuracy Error introduced by controlsError introduced by controls Inaccuracies by not using shortest Inaccuracies by not using shortest
range scalerange scale
Grunt Productions 2007
Radar Radar ErrorsErrors
Index ErrorsIndex Errors Strobe AccuracyStrobe Accuracy Error introduced by controlsError introduced by controls Inaccuracies by not using shortest Inaccuracies by not using shortest
range scalerange scale Sloping beach/HOTSloping beach/HOT
Grunt Productions 2007
Grunt Productions 2007
Grunt Productions 2007
Radar Radar ErrorsErrors
Index ErrorsIndex Errors Strobe AccuracyStrobe Accuracy Error introduced by controlsError introduced by controls Inaccuracies by not using shortest Inaccuracies by not using shortest
range scalerange scale Sloping beach/HOTSloping beach/HOT
Grunt Productions 2007
EXECUTIONEXECUTION
Ensure chart and PI’s are accurate.Ensure chart and PI’s are accurate. Conduct time check.Conduct time check. Maintain constant commentary - Maintain constant commentary -
“30 yds port of track with a “30 yds port of track with a further 150 yds of safe water to port. further 150 yds of safe water to port. 3 cables to run to the wheel over. 3 cables to run to the wheel over. Recommend come right to new Recommend come right to new course 095 to regain”course 095 to regain”