Sea School oopv Nav General study guide

5.0 (1 review)
1 / 110
the term slack water during a tidal change means
Click the card to flip 👆
Terms in this set (110)
when plotting a voyage you shouldnever rely on a floating buoy to maintain its exact positionthe difference in height between low and high tide is referred as therange of tidefrom seaward the IALA region B red and green horizontally-banded buoys refer topreferred channelsdetermining the heights of land features on most charts unless otherwise stated the reference datum ismean high waterred or green lights may appear onhorizontally banded buoysthe depth of the water on a chart is thevertical distance from the chart sounding datum to the ocean bottoma north hemisphere wind which shifts in a Counter CLockwise motion is called thebacking winda vessels position acquired by using at least three or more bearings are called aFIXMean lower low water is the reference plane used forsounding on the US east and west coastA single line of position combined with a dead reckoning position results in aestimated positionthe sun and moon align twice each month-- what type of tide can be expectedspring tidea buoy mark with a composite group -flashing light indicates apreferred channelon the US east and west coasts charted depth are taken frommean lower low watera weather forecast expects a Backing wind. in the northern hemisphere this would indicate that it willshift in a counter clock wise mannerwhat type of tides occur when the sun and moon are at right angles (90 degrees) of each otherneap tideif lighted preferred channel buoy will show acomposite group flashing (2+1) RED OR GREEN LIGHTA WEATHER FORECAST expects a Veering wind, in the northern hemisphere this would indicate that it willa shift in clockwise mannerthe length of a lunar day isabout 50 minutes longer than the solar daya lighted preferred channel buoy may show acomposite group flashing lightto determine the depth of the water what should you apply to your depth finder readingadd the draft of the vessela local wind which occurs especially during the day owing to the land heating up is asea breezea location that is acquired by using three or more intersecting lines of postion taken at nearly the same time is aFIXflashing green lights may appear onhorizontally banded buoyswind resulting from the cooling of a land mass more quickly especially at night than adjacent water is aland breezethe term MEAN HIGH WATER is the average height ofall high waters over a 19year spanwhich term best describes an accurate position which is NOT based on a any prior positionFIXa safe water mark may exhibitvertical stripes white lightmean low water is an average height ofall low water over a 19 year perioda position obtained using only the vessels course and speed from a known position is adead reckoning positiona vertically striped aid to navigation buoy may belighted with a white lightthe path that a vessel is expected to follow is called thetrack linewhen plotting a dead Recocking DR you should always start from aknown positionwhat best describes a safe water mark-- painted and lightedred and white stripes with a morse A lighta lighted buoy with a red spherical top mark indicatesa safe water buoyhow many high tides usually occur each day on the east coast of the UStwowhich IALA region B aid to navigational mark may only be lettered an NOT numbereda spherical buoyThe scale on a nautical chart is given as 1:80000 this means the representative is1 inch on the chart equals 80000 inches on the earths surfacenun buoys may show onlyflashing red lightsa description on a nautical chart noting a RACON indicatesRadar Transponder beaconlegends printed on a nautical chart in CAPITAL LETTERS show tha the association landmark isCONSPICUOUSa non-lateral aid with a red spherical top mark assists in identifying with atona safe water markwhen there are 2 high and 2 low tides in a 24 hour period this Is called asemidiurnalyou are in bound on course for the harbor and sight a white light showing a Morse (A) .__ to port for safety you shouldleave the buoy to portfrom seaward you enter the main channel, the buoy numbers on the starboard side of your vessel shouldINCREASE and the buoys are REDin IALA region B lateral system a CAN BUOYGREEN (GREEN CANSthe best term that describes the difference between the heights of low and high tide is thetidal range or rangeneap tides occur when the sun and moon areat right angles to each othera mid channel buoy if lighted will shownon of the abovespring tides occur when the sun and the moon arenearly in line with the earthyou are outbound to sea in a buoyed channel and observe a quick flashing green light on a buoy ahead of you , in IALA region B you should leave the buoyTO Starboardyour vessel changes heading to starboard the compass card in a magnetic compass willremain aligned with the compass cardwhen entering a vessel traffic separation zone from sea a lighted buoy to be kept to starboard shall have ared lightthe symbol which appears beside a light on a chart reads "Gp Fl G(2) 12 sec 160ft 19M which characteristic of light color does it possesit has a green lightwhich symbol represents a warm frontline with red half circles on one sidewhen entering from sea in the US waters what buoy should be left to portodd numberslateral buoys which only mark the left or right side of a channel shall NEVER exhibit a light characteristic ofcomposite group flashing (2+1)which chart projection is most suited for coastal navigationMercatorto make a correction to your compass course (PSC) you would find the variation on a Mercator charton the compass rosea conical buoy (refered to as a nun buoy) willbe red in color and even numbered (red even nun)the instrument that reads atmospheric pressure differences and changes isbarometerprior to reading an aneroid barometer you should tap the face lightly with your finger tobring the pointer to its true positiona cold front symbol on a weather chart is represented byline with blue trianglesfixed yellow lights may appear onspecial purpose buoysthe weather forecast stated that an occluded front will occur what is the weather chart symbolline with purple half circles and triangleswhich buoy could be used to mark a special anchorageyellow buoy lettered Blocal notice to mariners reports dredging operations are underway in your vicinity which buoy indicated the dredging areayellow buoythe weather forecast calls for a stationary front which weather symbol will represent thisline with red circles on one side and blue triangles on the othera white buoy with an orange colored rectangle on it is used to indicategeneral informationthe chart projection most commonly used for navigation is themercatoran occluded front is represented by which color linepurplethe description RACON alongside an illustration on a chart would meanRadar transponder beacona line of position made by sighting two charted object in a direct line is a called arange linechart letters printed in CAPITAL LETTERS show the associated landmark isCONSPICUOUSto measure the distance on a mercator chart between two waypoints which tool would you use to measure the distancedividersdistance on a track line is measured on a mercator chart by using thelattitude scale nearest to the track lineif lighted, white lights may be found onInformation and regulatory buoysconspicuous landmarks on a chart legend are printed inCAPITAL LETTERSinformational and regulatory buoys arewhite with orange geometric shapesthe rise and fall of the oceans surface due to a distant storm in known asswellisolated danger buoys on IALA region B waterways are painted with alternatingred and black bandsnormally weather patterns in the US generally move fromwest to eastwhich federal agency maintains aids to navigation in the UScoast guardunited states coast guard is responsible for publishing thelight listswhat critical source of information is to be used in correcting charts and maintaining them up to datelocal notice to marinersthe source to find the number of a chart for a certain geographical areacatalog of nautical chartsa weekly source for mariner warnings of serious defects or important changes to aids to navigation are publishedlocal notice to Marinersthe us coast pilot (volume I thru XI) is published by which US government agencyNational ocean servicelight lists that are published for US coastal waters arecorrect only to the date of publications and must be updated thereaftercompass deviation is caused by theinfluence of the magnetic materials of the vesselmagnetic north varies from true north because ofVariationlength of nuatical mile2000 yardslight lists of coastal waters publishedcorrect to date of publicationmagnetic north differs vs true northvariationspecial purpose buoyyellow buoyif lighted a safe water buoy will show awhite light with morse code Alubber line on magnetic compassshows the way the vessell is headedfathom vs feetfathom is 6 ftsea smokemost common in fallflood tidemoving towards the landDistance used in navigation chartlatitude scale