MAN Flashcards
Manoeuvring
Propeller
General concept
- (theoretical) pitch: theoretical distance of 1 full turn
- propeller speed (=theoretical speed): distance [M] in solid mass in 1 hour => pitch * rph
- slip= propeller speed ./. actual speed
RH prop
right-hand edge of top blade further away than left-hand edge
Prop Effect
(forward)I
counterpressure from water => greater at bottom arc
prop wash only pushed astern towards rudder
Prop Effect
(astern)
3 effects:
1. counterpressure: R=F1-F2
2. upward wash pushed against stern
3. upward thrust raises water level
Why most FPP prop right handed
VPP behavior
- most FP right-handed, for easier evasive stb manoeuvres
- VPP (prop shaft turning clockwise) behave in astern like left-handed props => push stern to stb in astern!
Twin screws
Fixed: outwards (stb manoeuvrability)
VPP: inwards
Alternative propulsion
- Azipods (electrical, steerable thruster)
- water jet
- Voith-Schneider
- whale tail
Rudder
fundamentals
- optimal bent of prop wake
- minimum drag
=> lift = rudder force “R”
Rd := transverse force (dwars)
Ra := drag force (achterwaarts)
Rudder
types
- plate rudder (dated)
- spade rudder (typical)
- flap rudder (hinged flap to diverge wash to athwart thrust by 2x rudder angle)
- (simplex) balanced rudder (part of blade in front of rudderstock => pivotal point further back)
- mariner rudder (rudderpost / rudder horn integrated into ship construction => rudder not just hanging from rudderstock)
- fishtail rudder (shaped like Fischli)
- Oerts rudder (defined by profile; hollow; strong; requires support)
- Stork-Jaffa (used on barges to deviate thrust up to 180 deg)
Steering: forces
- leaning / inclination inwards (vertical torque: Rd ./. Ad)
- turning (horizontal torque: Rd ./. Ad)
- transverse movement outward (Bd)
- leaning/inclination outwards (vertical torque: Bd ./. C = water resistance)
- loss of speed (Ba)
Ad and Rd => leaning inwards and turning
Bd => transversing
Bd and C => leaning outwards
Ba and Ra => slowing down
Manoevring data
- Turning Circle data
- Stopping Distance and crash test (due to ^2 => 1/2 speed => 1/4 distance)
- Speed Tests
- Man Overboard Manoevre tests
- ZigZag tests
………. - Pilot Card
- Wheelhouse Poster
Turning Circle
practicalities
- ship turns around the turning point (D), 1/4-1/5 from bow
- with reduced UKC => water pushed away by stern has greater difficulty to pass between hull and bottom => greater turning circle
- lower speed => smaller centrifugal forces => smaller turning circle
Turning Circle
diagram & terms
- Kick: sideways overshoot of lubber line caused by transversing of Bd; ca 40-100 m
- Advance: forward (to 90 deg course chang; circa 4x L)
- Max Advance: forward (furthest point the stern will touch)
- Transfer (90): sideways from max kick to 90 deg course change; ca 2x L
- Max Transfer: sideways from max Kick to max circle (greates distance in diagram)
- Tactical Diameter: sideways from max Kick to 180 deg; ca. 4x L
Turning circle
names for 90 / 180 deg
90: Advance (fwd)
90: Transfer (abeam; from kick)
180: Tactical Diameter (from kick)
Watches
00-04: Middle
04-08: Morning
08-12: Forenoon
12-16: Afternoon
16-20: Evening = Dog
20-24: First
course ./. heading
Course: what you are supposed to steer
Heading: heading at this moment
Lookout
To be maintained at all times:
1. continuous state of vigilance (sight/hearing/other means) re changes in operating environment
2. situational awareness re risk of collision, stranding, dangers to navigation
3. detecting ships, aircraft, people in distress and debris and other hazards to navigation
Watchkeeping principles
- officer in charge of watch keeps watch on the bridge
- no other duties assigned, which would interfere with safe navigation (e.g. paperwork)
- maintain proper records of movements and activities
- compass error is determined at least once a watch, and ideally after large course changes; compasses frequently compared and repeaters synchronized
Operational test of shipboard NavCom equipment
Shall be carried out at sea as frequently as practicable and circumstances permit. Particularly before arrival/departure, when hazardous conditions affecting navigation are expected.
Tests to be recorded
OOW to notify Master
(Master’s standing orders)
1. restricted visibility
2. traffic/movements causing concern
3. difficulty to maintain course
4. failure to sight land/markswhen expected
5. sight land/marks when not expected
6. unexpected change in soundings
7. breakdown of propulsion/steering/essential NavCom equipment
8. Radio equipment failure
9. if in doubt about weather damage in adverse conditions
10. encountering a hazard to navigation
11. any other emergency or when in doubt
Navigating with Pilot
- Master remains in control (conn)
- Master/Pilot exchange
- Bridge team management
- maintain proper records and plot position and movements
If in doubt
* seek clarification from pilot
* if doubt maintained: notify Master
* meantime take action as deemed appropriate
Ship at anchor
Watchkeeping
if Master deems it necessary, a continuos navigational watch (not anchor watch) shall be maintained at anchor:
- position
- traffic
- lookout
- exhibit appropriate lights
- anchor dragging
- inspection rounds
- notify master if visibility drops; anchor drags,
Ship in port
When safely moored or at anchor under normal circumstances in port, Master shall arrange appropriate and effective watch to be maintained for safety and security
Turning Circle
attention: transfers relative to kick not lubber line
MOB
Williamson Turn
Lines
Prepare for mooring
- sufficient crew
- mooring wires/ropes
- heaving lines
- fenders
- shackles
- anchors ready (lashings off; clear anchor tubes; break/clutch checked; hydraulics/electrics ready; chain free)
- capstan/windlass ready
- intercom/walkie-talkies ready
beware of snapback! (chafing; heat; melting)
always moor bow into current!
Lines running
prepare for unmooring
- check instrument/systems
- ready for sea (cargo; pax; stowed&lashed)
- single up
- stow fenders and ropes
Fore’cstle layout
1: warping head
2: drum
3: bollards / bitts
4: stopper eyes
5: fairlead / roller
6: centre lead / panama lead
7: roller fairlead
8: headline
9: fwd spring
Snap back
Mooring PS
Mooring Stb
Unmoore, PS alongside; ship on course
Unmooring; stb alongside; on course
careful for Alt.2, when in position 2, don’t give hard port rudder (to avoid stern collision w quay)
alt: fisherman’s spring
Mooring with current on the bow
posi 3: counter rudder on time (so bow not pushed against quay)
Mooring against current w anchor
Turning in current w anchor
Departure
Current on bow, ship on course
Strong aftspring and bowline
Rudder away so current moves bow out
Cast off aftspring
Current pushing stern away
Cast off bowline
Departure
Current on stern, ship on course
FWD spring; AFT line
Rudder away so stern swings free
Belay aft line; engine astern; rudder midships
Pay out FWD spring; cast off
Only cast off aft line once engine fwd
Anchoring:
preparations
Anchor winch:
arrangements
Spurling Pipe
detail
Anchor winch
Anchoring:
how much chain to pay out
in deep water: pay out chain with windlass
Anchor chain marking
Anchoring :
V-shape
prevent yawning
Anchoring:
dropping and running
(Bahamian moor)
Anchoring:
dangers
- heavy gear
- high voltage / hydraulics (winches)
- confined space/oxygen depletion (chain locker)
- metal dust & splinters
l
Dropping Moor
- sail upstream
- lee anchor first
- fall back
- windward anchor
- position
better: running moor (more control)
Running Moor
- drop windward anchor
- pay out chain sail upstream
- drop lee anchor
- position
better than Dropping Moor: more control
Result of Running and Dropping Moor
Entering port with cross current
bahnkurve; current does the job to align stern
Fisherman‘s Spring
Anchor Winch
Narrow bend
Current on Head: keep to outer bend (larger turning circle; current ahead)
Current on stern: inner bend (current will help turn stern)
Ship ready for sea
ALWAYS WHEN A SHIP LEAVES PORT SHE SHOULD BE READY FOR SEA!
crew - vessel - pax - cargo
- ALL LOOSE ITEMS FROM DECK
- CARGO SECURED AND SEA-PROOF (MOST ACCIDENTS IN ROUGH WEATHER OCCUR AS A CONSEQUENCE OF SHIFTING
CARGO) - ANCHORS SEA-PROOF (STOPPERS, HOOKS/DEVIL’S CLAWS, NAVAL (CHAIN) PIPES CLOSED);
- CROCKERY AND SUPPLIES STOWED AWAY.
- ENGINE ROOM SEA-PROOF
Preparing when facing severe weather
WHEN FACING SEVERE WEATHER, FOCUS ON THESE ASPECTS:
=> people in - water out
1 EVERYTHING SECURED
* CARGO SECURED (CHECK AGAIN)
* GEAR SECURED (CRANES, BOOMS, SAILS, GANGWAY, ETC
* ANCHORS SEA-PROOF (CHECK AGAIN);
* GALLEY AND STORES SECURE (CHECK AGAIN)
2 SHIP WEATHERTIGHT?
* CLOSE ALL PORTHOLES INCLUDING BLINDS
* CLOSE ALL VENTILATION OPENINGS
* AS LONG AS WATER CANNOT ENTER, THE SHIP CANNOT SINK!
3 SAFETY
* CAN CREW MOVE ON DECK SAFE? (SAFETY LINES, HARNESS,
* IS GALLEY INFORMED
* ARE GUESTS INFORMED
water out - crew in
continuously check during
Storm Manoevres
- in irons (not preferable for large vsls)
- heave-to (4 points on bow)
- running adrift (= let go)
- scudding (= lenzen)
Heaving-to
- Sufficient sea room
- Wind and sea at
3-4 points of the bow - Low speed
- Leeward side is created
- Less tension in the fore and aft ship
- Large vessels less severe torsion
forces - Less damage to ship and cargo
- Oil film calms sea at windward side
(careful deck can be slippery
Scudding
= Lenzen
- When the ship runs before
sea and wind, the impact
of the waves is less. - There must be sufficient
sea room - negative impact on manoevrability (loss of stearing on wave crest) and stability
FOR SMALL SHIPS THERE IS THE DANGER OF BROACHING OR BOW DIVING
- FOR BIG VESSELS HEAVY ROLLING CAN OCCUR
- THE STABILITY IS INFLUENCED NEGATIVELY AND THERE IS A GREAT DANGER OF CAPSIZING
- WHEN THE WEATHER GETS WORSE IT IS DIFFICULT TO NOTICE
- IT IS DIFFICULT AND DANGEROUS TO TURN THE SHIP AROUND, TO CARRY OUT ONE OF THE OTHER MANOEUVRES
- WHEN THE SHIP HAS THE SEAS FROM THE QUARTER, SHE WILL ROLL HEAVILY AND SHIP A LOT OF WATER ON DECK,
ALSO NEGATIVELY AFFECTING THE STABILITY
(Water) Pressure distribution around moving vessel
MAN
water flow around vessel in narrow channel
MAN
faster flow of reverse current => lower water level
Bank effect
MAN
faster flow of reverse current => lower water level
not: suction
but: pushing (sliding downhill)
If vsl slowly moves towards bank and helmsman gives counter-rudder => stern pushed even closer to bank (turnin point D ~ 1/4 from bow) and reverse current at stern even faster
Navigating in narrow or shallow waters
MAN
hydrodynamics have a major impact on your manoeuvrability: SQUAT, bank effect; passing/overtaking
- moderate speed
- stay in middle of fairway
- once vsl responds less or moves from middle: slow down or stop
Meeting in narrow channel
MAN
- in approaching bow waves (+) will push them apart
- next to each other: opposite reverse currents cancel each other out; water at normal (i.e. high) level, keeping both vsls apart
- at sterns passing, the sterns are pushed towards each other in the stern cavities: port rudder & kick forward
Overtaking in narrow channel
MAN
- more dangerous than meeting
- reverse currents between them double => water drop between them is significant => pushing the vsls together (pressure strongest fwd and aft)
- danger of collision highest when overtaking bow close to other vsls stern/aft of midships
- slow down & keep distance
- once almost past, overtakers stern will be pushed to other vessels bow => rudder starboard & kick
Reverse current
vs
Reverse flow
Locking
- slow entrance to allow water out
- FW/SW flow (surface: FW -> SW)
- ropes/lines/fenders
- docking up/down?
- windward
- prop wash of other vessels
- enter/leave in middle: reverse current
MOB
Don’t let it happen:
- both feet on deck
- don harness when leaving deck
- no sitting on railing
- no peeing
- safety lines and Storm nets
MOB boat: SART; life jackets; survival suits; VHF; min 2 crew
Pilotage requirements
Whether pilot is required:
ALRS; Vol. 6
IAMSAR
International aeronautical and maritime search and rescue manual
Volume III
SAR coordination
RCC
Functions:
SAR Coordinator
SAR Mission Coordinator
OSC
AMVER
(MAN)
Automated Mutual Assistance Vessel Rescue System
worldwide system to maintain estimated positions of voluntary participating vsls to
support SAR and make info available to all RCCs
GMDSS equipment
MSI Receiver
VHF/HF/MF DSC radio
Inmarsat ship/earth station
handheld VHF
EPIRB
SART
Main features GMDSS
3 basic principles:
1. ability to receive MSI (anytime/anywhere)
2. initiate distress alert/message (anytime/anywhere)
3. ability to be retrieved by SAR units anywhere
Distress alerts to contain
- MMSI of vsl in distress
- Time in UTC of distress
- Position of vsl in distress
- Format of distress (fire, collision, capsize…)
GMDSS sea areas
A1: < 30 M
A2: < 200 M
A3: 70 N -70 S
A4: all except A1-3
GMDSS equipment
SOLAS communications equipment:
- INMARSAT ship/earth stations
- VHF/MF/HF DSC radios
- MSI receivers (NAVTEX; SafetyNET)
- handheld VHF
- EPIRB
- SART
SAR patterns
- Expanding Squares (SS)
- Vector Search (VS)
- Creeping Line
- Parallel Swap
RCC
(MAN)
Rescue Coordination Centre
- promoting efficient SAR organization
- SC: coordinating conduct of SAR ops within a region
SAR coordination
(MAN)
3 levels of coordination:
- SAR coordinators (SC)
- SAR mission coordinators (SMC)
- On-Scene coordinators (OSC)
Manoevring data/characteristics
MAN
to be available on bridge:
- turning circle
- stopping distance / crash test
- speed tests
- MOB tests
- ZigZag
distances Turning Circle
Kick: 40-100 m
Transfer: 2x LOA
Advance; Tactical Diameter: 4x LOA
