How to use a radar effectively?

[Brews]

Firstly, Colregs state that if you have an operable radar on your boat, you must have it on at all times,

You need to log and track all returns that are on a collision course (decreasing distance, no change in heading). Take early and obvious evasive action.

Those are the most important things.

In Canada, CPS offers a 2-day radar course. It's not expensive, and worthwhile.

[StuM]

Originally Posted by Brews

Firstly, Colregs state that if you have an operable radar on your boat, you must have it on at all times,

Reference please?
(Or are you just basing that assertion on your interpretation of Rule 7(b) )

[Brews]

No interpretation necessary, it's explicit. Although, that may be a Canadian Modification.

Basically, whenever the vessel is underway, except in harbours in good visibility.

Rule 7
Risk of Collision
(a)
Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist.
(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.
(c)
Assumptions shall not be made on the basis of scanty information, especially scanty radar information.
(d)
In determining if risk of collision exists the following considerations shall be among those taken into account:
(i) such risk shall be deemed to exist if the compass bearing of an approaching vessel does not appreciably change,

(ii) such risk may sometimes exist even when an appreciable bearing change is evident, particularly when approaching a very large vessel or a tow or when approaching a vessel at close range.

[boatpoker]

The most misused, misunderstood piece of navigation equipment ever. The recreational radar manufacturers have over simplified the use of this equipment in their manuals and by their use of "automatic" adjustments that they have much reduced effectiveness. Burying needed adjustments such as FTC, STC, Tune and Gain deep within menus instead of each of these being instantly available individual knobs that can be operated by feel without ever changing screens.Even down to the terminology they use .....rainclutter, sea state, etc. will not be found in any real radar course.

Terrific rquipment in the right hands

My radar certification course was 11 weeks with 7 days on the simulator and it took me every second of that time to get a basic handle on them.

If you can get your hands on a circa 80's Furuno radar manual you will learn more than you thought possible.

[Cheechako]

yeah read up. The bottom line is:
- Adjust your sensitivity according to seastate. I like to leave mine on the high side a bit. (I'd rather look for something that's not there when a big sea reflects back than miss something that is there.) Do this in the daytime to get some sense of what the conditions really are etc. Do this when you see a boat far off and set according to what your eyes see. ie: get familiar with it.
-Use the radar for 360 around you, you can be overtaken by a freighter in 20 minutes.
-With sensitivity set good you can see squalls, thunderheads and windspouts and correct course if possible.
-If a vessel sits in the same spot on your radar screen continuously, you are on a collision course.

[Lodesman]

Originally Posted by Brews

Firstly, Colregs state that if you have an operable radar on your boat, you must have it on at all times,

You need to log and track all returns that are on a collision course (decreasing distance, no change in heading). Take early and obvious evasive action.

Those are the most important things.

In Canada, CPS offers a 2-day radar course. It's not expensive, and worthwhile.

To be entirely pedantic, it says "proper use", not "at all times", so I think there's a bit of leeway there. To me, having it in standby and making periodic long-range sweeps is perfectly acceptable in clear vis conditions.


Personally I prefer North up. Chart is north up, I think in North up, and the radar aligns with what I see on the chart. It also makes it easier to tie in reported courses with targets.


For the OP, it is highly worthwhile finding someone who knows something about radar and having them show you how to work it on your boat. Don't know where you are located, but you might be able to scare up a knowledgeable sailor here on CF.

[Paul L]

Originally Posted by StuM

Reference please?
(Or are you just basing that assertion on your interpretation of Rule 7(b) )

The courts have not required radar to be on at all times. From the Granholm case.

I also reject plaintiff's contention that the EXPRESS must be condemned for failing to have her radar switched on during the evening in question. To reiterate: the EXPRESS was sailing in the open ocean on a clear night. Plaintiff cites no case requiring use of radar in such circumstances. My own research discloses none. The Fourth Circuit reached a contrary conclusion in British Transport Commission v. United States, supra. The district judge in that case rejected a contention that failure to use radar on a clear night constituted fault because it would have revealed the other vessel's existence. The district judge wrote:


"But [the mate] was not looking for anything to starboard; he had no reason to go to the radar to search in any direction. His failure to see the Duke [the other vessel] was not negligence, for it was not the result of neglect of an obligation. No obscurity obligated him to use his radar, and there was nothing else to put him on notice of any need for it."
The Fourth Circuit quoted this language with approval. 230 F.2d at 142.