Lesson 5 Navigation Instruments Lesson 5 Navigation Instruments
- Slides: 26
Lesson 5: Navigation Instruments
Lesson 5: Navigation Instruments · AGENDA: – Measurement of Depth – Measurement of Direction – Measurement of Distance – Measurement of Speed · Applicable reading: Hobbs pg. 110 -128.
Measurement of Depth · · Echo Sounder (fathometer) Hand leadline
Lead Line · · Manual method of determining depth Also allows for a sampling of the bottom type
Measurement of Direction · · Bearing: the horizontal direction of one terrestrial point as measured from another, expressed as an angle from 0 to 360 degrees. There are three references for bearings: – Relative – Magnetic – True
000 T / 270 R 270 T / 180 R 180 T / 090 R 090 T / 000 R
Measurement of Direction Visual Bearings can be measured in: 0 - Degrees Relative ( # # # R ) 0 - Degrees Magnetic ( # # # pstgc OR M ) 0 - Degrees True ( # # # T) The navigator must convert any of these types of bearings to True before they can be plotted on the chart.
Bearing Circle/Alidade · · Azimuth or Bearing Circle Telescopic Alidade
Bearing Circle · Telescopic Alidade
Measurement of Distance Radar - Distance is obtained by a radio wave that is transmitted into the air and returns as an echo. The time interval between transmission and return can be converted into a physical range. Used for distance (range) only!! Not normally used for bearings
Measurement of Distance STADIMETER Used to determine precise ranges between ships in formation
Making an Observation with the Stadimeter · Distance is determined by: distance = height of object / tan (angle)
Plotting Instruments Parallel Ruler
Plotting Instruments Parallel Plotter
Plotting Instruments Parallel Motion Protractor
Plotting Instruments Compass · Dividers ·
Plotting Instruments Nautical Slide Rule
Operation of Nautical slide Rule · Given two of the following, find the third: – Speed – Distance – Time
Measurement of Speed · · Speed over Ground (SOG) = true speed Speed through the water SPEED OVER GROUND • Direct output of many electronic navigation systems (GPS, Loran) SPEED THROUGH WATER • Impeller Log • Pitotmeter Log • Doppler Speed Log • Shaft RPM
Measurement of Speed Impeller Log
Measurement of Speed Pitometer (Pit) Log
Measurement of Speed Doppler Speed Log
3 Minute Rule · The Distance in yards that a ship travels in 3 minutes (D) is equal to the Ship’s Speed (Spd) in knots multiplied by 100. D = Spd x 100
6 Minute Rule · The Distance in nautical miles that a ship travels in 6 minutes (D) is equal to the Ship’s Speed (Spd) in knots divided by 10. SPD D= 10
REVIEW · · What does a fathometer measure? What does D=Speed x 100 tell you?
QUESTIONS? ?
- Active and passive instruments definition
- Pressure measuring devices
- New and navigation schemes selection of window
- Aim vor
- Us coast guard navigation center
- Ecdis safety settings
- What does the daytime aid to navigation mean
- Cyclone global navigation satellite system
- Terrestrial navigation equipment
- Strapdown inertial navigation system
- Joint navigation conference
- Effects of navigation acts
- Navigating
- Hdg navigation
- Qoverview
- Terrain types
- What is a draw in land navigation
- Daytime aid to navigation
- Global navigation solutions
- Coast guard navcen
- Slide navigation pane
- Mobile robot navigation with human interface device
- Navigation adalah
- Sun stone navigation
- Basic map reading skills
- Carm navigation
- Terrain features army