hello and welcome back to core eggs in depth today we're going to be taking a look at rules seven risk of collision as always we're going to look at the rule itself and then we're going to apply that rule in a couple of different situations it's a rule seven risk of collision first paragraph every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists if there's any doubt such risk shall be deemed to exist now you'll notice this echoes rule five where we were using all available means to keep a proper lookout now we have to use all available means to determine if risk of collision exists paragraph B proper use shall be made of radar equipment if fitted and operational including long-range scanning to obtain early warning of risk of collision and radar plotting or equivalent systematic observation of detected objects now radar plotting itself are covered in a different video which I'll link up in the card at the top but what this paragraph of the rule is saying is where you need to use systematic observation so radar plotting we're talking about taking a series of plots on the radar or visual plotting we're looking at taking a series of compass bearings we need to be systematic about it we can't just look and take one snapshot in time we need to do it systematically and observe it over a period of time to determine if risk of collision exists assumptions shall not be made on the basis of scanty information especially scanty radar information this is going back we need to take systematic observations so we need to take a series of bearings a series of radar observations scanty information is basically incomplete information we need the whole picture to determine if risk of collision exists we cannot make assumptions on scanty information then finally in determining of risk of collision exists the following considerations shall be among those taken into account now these are just among the considerations these are not the only ones but is among the ones that you need to take into account such risk shall be deemed to exist if the compass bearing of an approaching vessel does not appreciably change what we mean by this is if we put ourselves on the white vessel and we're going to observe the blue vessel we need to take a bearing of the other vessel now we take the bearing as the difference between our heading line and the bearing of the vessel and we need to continue to monitor that as we approach each other clearly in this case that bearing is not changing the vessel stays going down that same constant bearing which means risk of collision exists but that's not the full picture Biograph 2 says that such risk may sometimes exist even when an appreciable bearing change is evident particularly when approaching a very large vessel or a toe or when approaching a vessel at close range what does this look like well if we take the same situation but let's say we're approaching a significantly larger vessel now to take a bearing of it we need to pick a part of that vessel that we're taking a bearing of it's too large to just take a bearing of the whole vessel so in this case our bearing is going to be of the bow now watch what happens as we approach each other we're looking down that same bearing line we no longer looking at the bow the bearing of the bow has changed significantly but that does not mean risk of collision does not exist if we continue to play the animation we can see that even though the bearing change was evident risk of collision still exists we're approaching a very large vessel what about a toe if we go back to the same diagram but we'll put a tug in front of the vessel now we're going to take a bearing of that tug and see what happens when we continue to approach each other looking down that same bearing line we no longer looking at the tug the bearing of the tug has changed but if we continue on we can see there's still risk of collision even though that bearing change is evident because we're approaching a toe which has a very long length risk of collision still exists and that brings us to the end of rulz seven we've seen how we determine if risk of collision exists we seen the importance of systematic observation was seen that you cannot make assumptions and we've seen that if the compass bearing of an approaching vessel doesn't change risk of collision exists but we've also seen that in some cases even if the bearing is changing risk of collision may still exist hopefully you found the information in this video useful if you have thumbs up is always appreciated you've got any questions leave them in the comments below and to stay up to date with all my latest videos make sure you hit that subscribe button until next time thank you for watching and good bye