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RYA Instructor Conference 2019. How to teach RADAR without a RADAR?!? Andy Wright Yachtmaster Instructor Trainer. Protecting your Rights, Promoting your Interests. Aim and Objectives. Aim To introduce teaching RADAR concepts onboard with no RADAR available Objectives
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RYA Instructor Conference 2019 How to teach RADAR without a RADAR?!? Andy Wright Yachtmaster Instructor Trainer Protecting your Rights, Promoting your Interests
Aim and Objectives • Aim • To introduce teaching RADAR concepts onboard with no RADAR available • Objectives • Explain the key RADAR Concepts • Discuss and show examples of how RADAR concepts can be taught • Demonstrate some practical examples Protecting your Rights, Promoting your Interests
What does the RYA ask us to Examine at YM Offshore level?.................. • Absolute basics • Position • Navigation and Pilotage • Rule 5 (Lookout) • Rule 6 (Safe Speed) • Rule 7 (Risk of collision) • Rule 19 (Restricted Visibility)
What to our students need to know………… • Absolute basics: • After turning on… • Heading mode in use (HU,NU,CU) • Can identify and describe the basic use of EBL, VRM • Knowledge of gain, rain and sea clutter controls but understands that auto settings are usually sufficient on modern sets.
Position • VRM for position fixing • knowledge of the impact of topography on ability to use radar in pilotage waters • understand reasons for avoiding using an EBL for position fixing due beam width error and accuracy of bearing due display mode (Head up (relative bearing), North up (true bearing), Course up (pretend true if ground stabilised) • when using radar range and bearing is suitable e.g. with Racon or LANBY.
Navigation and Pilotage: • Sat derived positions • Understands using radar overlay on a chart plotter gives an independent means in pilotage waters. • Distress Signals (SOLAS Annex IV): • Understands the operation of Search and Rescue Radar Transponders and how it looks on a radar screen at long, medium and close ranges
Look out (Rule 5) • Knowledge of ‘all available means’ includes radar if fitted and when appropriate • Knowledge of monitoring a target’s range and bearing using VRM, rings and EBL to assess risk of collision • Safe Speed (Rule 6b) • Knowledge of the need to consider the impact of a radar and its operators effectiveness due to sea state and traffic density, rain etc when setting a safe speed (Rule 6)
Risk of Collison (Rule 7) • Understands the risk of making decisions based on scanty information, particularly RADAR, • Understand importance of training/experience if intending to use radar for Colregs or pilotage, • Knowledge of ‘radar visibility’ of common vessel construction materials (wood, GRP, metal or ferro-crete boats) • Understands the importance of correctly mounting a radar reflector
Restricted Vis (Rule 19) • Understands action to take if risk of collision detected only by radar (19d) • understands the relationship between (relative motion) track of a target and actual direction of travel of the target (very simplified interpretation of OWA triangle NOT full plotting with projected TCPA etc) • knowledge of automatic tracking aids and small boat radars (eg MARPA) and limitations imposed by nature of sources ()e.g. no compass, so your heading is actually COG) and or significant variations in vessel speed and heading preventing accurate calculation
RADAR Concepts • Collisions – Head up • EBL • CPA • TCPA • Relative speed and motion • Navigation – North Up • Range and bearing • VRM fix • Pilotage • VRM Parallel index • Weather – Head up or North up
But first this………………. • The 6 minute rule • 6 minutes is 1/10th of an hour. • In 6 minutes at 6 knots you travel 0.6 Nm • In 6 minutes at 10 knots you travel 1.0 Nm • In 6 minutes at 25 knots you travel 2.5 Nm • So we always plot in 6 minute intervals
Using the EBL for collisions avoidance • It’s a great way to check the crews bearings • It gets us using the RADAR • It allows us to make a decision early about a collision
000 8 6 nm 1 nm 1200 – 040 1206 – 041 1212 - 042 EBL
000 8 6 nm 1 nm 1200 – 318 1206 – 313 1212 - 305 EBL
000 8 6 nm 1 nm 1200 – 027 1206 – 025 1212 - 017 EBL
000 8 6 nm 1 nm 1200 – 300 1206 – 302 1212 - 304 CPA 1.2 nm
O – W – A What does it mean? • When we are plotting we have letters to help us remember what is going on! • Maybe remember a simple plot to show students on a course? • O = ‘Original’ Plot of the contact • W = Signifies ‘Way’ • A = Signifies ‘Another’ • O – W is ‘Own Way’ • W – A is ‘Way of Another’
000 8 6 nm 1 nm Head Up 1200 – 300 1206 – 302 1212 - 304 Vessels true course 050 (add you hdg to other ships heading – its relative!) Vessels true Speed 2.5miles (in 12 mins) – 12.5 knts O A CPA 1.2 nm W
120 10 6 nm 1 nm x North Up CPA 1nm Target true heading 090 T Overtaking W A O
VRM 3.5 miles VRM – will give a 3 point fix
Range: 3.67 Bearing: 048
True and relative motion • RADAR sets can display true or relative motion • Sets on small boats can usually only display relative due to input restrictions • So we have to interpret the picture (without a RADAR!) • The problem we have is that we stay stationary (seemingly) in the centre of the RADAR screen. But of course we know we’re moving, and the targets around us are moving, so they're moving relatively to us. When we avoiding collisions (or not) we need to make the picture (or plotting sheet) into true motion.
O A W
Head Up O A W
O W & A Head Up
Chart table RADAR • Counters to simulate true and relative motion (using plotting sheet) • Draw EBL on a plotting sheet with CPA: • Demonstrating a collision situation • Vessel passing ahead and astern • Demonstrate a VRM 3 point fix • Demonstrate a VRM Range and Bearing • Draw a collision using a O, W, A Triangle (CPA, TCPA, boat speed and aspect) • Use a VRM to run along a wall or coastline • Head up and North up Plots
What else can we say about RADAR? • Mini Automatic RADAR Plotting Aid (MARPA) • How to acquire targets • What information it gives us • Limitations • Number of contacts • Symbols and vectors • Trails • Tracking weather • Rule 19
Rule 19 Don’t turn to Port Don’t turn towards the vessel
Now its time to get creative………… • Using the assorted bits and pieces scattered around, have a go in small groups re-creating some of the RADAR concepts we have looked at? • Demonstrate a EBL on a contact with various CPA • Create a OWA plot • Make a Rule 19 plotting sheet place various vessels to test the correct decision • Re-create the true / relative motion scenario
Conclusion • Aim • To introduce teaching RADAR concepts onboard with no RADAR available I hope the session has been useful and inspired you to explore how to teach some RADAR concepts without a RADAR. Any questions????????