Radar

I'm new to using radar on a boat and I'm trying to learn its utility. I have nearly three decades of using weather radar on airplanes so I'm familiar with radar general principles and the fact that using radar well involves equal measures of science and experience plus a pinch of art. I'm using the radar on the Ohio River at the moment, but I will be making a cruise in Green Bay/Door County in August to "get my feet wet" in Great Lakes cruising. I intend to use it on a Great Loop voyage in sections starting as early as this fall.

First question: If I leave the gain in AUTO, about the only vessels I see on the river are large towboats with barges. If I turn the gain up to 90%, then I see just about every vessel on the water. Is this normal or is there an issue with the antenna or radome or perhaps the radar transmitter output power?

Second question: If I'm cruising on the Tenn-Tom this fall, I will encounter fog. Is it reasonable to use it in such conditions? My gut says no, especially given my low radar experience level.

Third question: What utilities do you use most often or find most useful?

Casperscruiser,

In reference to your "Second Question" about using or not using radar, I believe the following navigation rule applies:

"11. Am I required to have Radar? Radar is not required on vessels under 1600 GT (33 CFR 164.35), however, Rule 7 states that proper use shall be made of radar equipment if fitted and operational. In other words, whoever has one must use it. The Navigation Rules are not meant to discourage the use of any device, rather they expect prudent mariners to avail themselves of all available means appropriate...as to make full appraisal of the situation (Rule 5), e.g. the use of radar. At issue is whether the use of radar is appropriate in the prevailing circumstances and that is a determination made by the Master; and, ultimately decided by a trier of fact.

Should you be in a collision how would a judge/jury rule on your contention that the use of radar was impracticable (due to electrical drain, crew shortages, etc.)? Also, if a collision does occur, then there was obviously a risk of collision beforehand. Could the determination of that risk have been made sooner with the use of radar? It is difficult to answer such questions because the circumstances of each case are different.

More importantly, remember that Rule 7 specifies that assumptions shall not be made on the basis of scanty information, especially scanty radar information."

The link to this rule is:
https://www.navcen.uscg.gov/?pageName=n ... FAQ#0.3_11

Maybe the more appropriate second question should be " Is it reasonable for me to cruise in such conditions?". The answer would then depend on your experience and comfort level with the radar. If you choose to go out and navigate in the fog the risk would be far greater to not use it than to blindly attempt to navigate without it no matter your experience. If you are not comfortable with it then practice with it more until you are or wait for a better weather window.

I'm new to Ranger Tugs and radar, but not to long distance cruising. I have 2,000+ inland river cruising miles on trips ranging from 75 miles to 650 miles. On days when fog was present, I simply did not leave until I had adequate visibility for safe visual navigation.

What I am trying to determine is this: Does the Garmin radar typically installed on Ranger Tugs have the capability and utility to safely reduce the visibility minimums needed for cruising? As mentioned, I have many years experience with airborne weather radar. Early in my career, I flew light twin-engine aircraft. They hold a position in the aviation world similar to where a Ranger Tug is on the boating food chain. I learned then that the effectiveness and utility of airborne weather radar is highly dependent on antenna size, radome and installation quality. I suspect the Garmin radar on a Ranger Tug has a utility similar to those radars, which means fairly limited usefulness. Is this a fact?

Red Raven and Dale777, are your vessels equipped with radar and, if so, in what ways do you use it? Can you answer my question about gain level?

I have been out on our boat in pretty much zero visibility out of Bodega Bay. First I slow down. We left the marina and went 20 miles up the coast one day and hit are target buoy right were it was supposed to be. Never saw anything but grey for almost two hours. Is it more stressful, you bet. But it can be done. And it is a great sense of accomplishment when you navigate successfully.

I am a fan of the newer technology radomes. Like the Garmin Fantom which we have on our R31. However, the older radars work well too.

Navigating via radar is definitely possible with the systems on our boats. Autopilot is very helpful as you can get turned around easily in the fog. It can be done, but I would recommend starting small and working your way up. Maybe start with a small night cruise, no fog and get used to navigating by the instruments. Learn how to adjust the gain on your radar and interpret what it is telling you.

Happy Navigating!

The best way I've found in knowing how well the RT radar provides useful meaningful data on my chart plotter is to start off using it in daylight with clear visibility. As you go along and you visually spot objects, other boats, buoys, etc look at their signature on the radar screen. Are the signatures small, large elongated and do their positions match up with the object you see on the water. Sometimes the radar overlay will look confusing with large smudges showing land masses. Play with the radar's collision alert feature as well. You can assign a radius around your boat and be alerted when some object enters this circle.

Hi CasparsCruiser,

Yes we have radar on the boat. I often turn it on even in good weather to stay familiar with its performance characteristics and adjust the settings (no, I typically don't use the Auto setting but have not had to set it anywhere near 90%). The good news is in fog there is usually not wind and thus little waves. With little wave clutter the radar performance is much more reliable. When properly adjusted it works very well. We don't choose to go out in the fog but have been swallowed up in it unexpectedly several times. With the combination of the radar, GPS, and AIS on, going slow, and following the horn protocol for fog (one long blast every 2 minutes) we felt fairly confident and secure in proceeding.

In one instance we could not see more than about 100 -150 feet we could see a small boat approaching on the radar (no AIS signal and no horn sounding). We eventually passed port to port about 150 feet apart just so that we could barely see him (it was a sailboat). He never did sound his horn but surely could hear us. He must have seen us on his radar as well and just thought that was sufficient.

In summary, it works well enough to give me confidence we can handle fog if it comes up unexpectedly but I still don't venture out if I know it is expected.

Curt

baz":2djjhnn4 said:

........start off using it in daylight with clear visibility. As you go along and you visually spot objects, other boats, buoys, etc look at their signature on the radar screen.......

Click to expand...

That is exactly what I've been doing-- using it daylight good visibility and comparing the radar's depiction of the water world with what I see out the window. I've been adjusting the gain and have been impressed how it will display some pretty tiny vessels and buoys. However, it seems that it takes a lot of gain to do so. It's going to take some time before I develop enough confidence to use it in fog. I am also anxious to try it out on more open waters than the Ohio River. I'll get my chance if my proposed cruise on Lake Michigan's Green Bay comes together in late July/early August.

I cruised back from a waterside bar & grill on the Ohio River tonight just as it was getting dark. The radar alerted me to an approaching towboat before I visually identified it. Anybody who has cruised the inland rivers knows that, despite their size, towboats are hard to see at night. Score one for the radar.

We had to use radar and autopilot yesterday. St. John's river below Jacksonville, visibility under a mile, river is wide and could not see AIDS visually, but clear on radar. AP guide to kept is in middle of channel, but net to check it as it sometimes cuts corners. Ships and labs arks visible on radar, but plastic pleasure boats are not. Ran at trawler speed, maybe 7 knots. Gonna get a reflector. Still love our Ranger Tug

This is what I use for a radar reflector.
https://www.practical-sailor.com/issues/27_16/features/4567-1.html

When I purchased mine it was reasonably priced. It now seems to have increased dramatically.... maybe it's in short supply. 🙁

This one (the Model M-2) is also highly recommended... and is a more reasonable price IMO.

http://www.downwindmarine.com/Mobri-Radar-Reflectors-p-91001394.html

Newbie question- If you are running active radar, is there a need for a radar reflector? Won't other boats with radar 'see' your radar signal?

ixlr8":1b178xoq said:

Newbie question- If you are running active radar, is there a need for a radar reflector? Won't other boats with radar 'see' your radar signal?

Click to expand...

Radar does not transmit to other vessels. It transmits and received a bounce back beam off of a vessel or object and that is how it picks up objects. The reflector allows the transmitted beam from another vessel to be picked up better on your boat, hence a better reflection back to the transmitting radar.

To see how affective (or not) your radar reflection is, have another boat with radar tell you how well they see you on their radar display. If you're at a Tugnuts gathering this should be an easy thing to arrange. 🙂

If you have the time you could make this evaluation with stock configuration vs. a new radar reflector you're wanting to install to determine if your money has been well spent. 😱

On a trip last weekend, I had a brief discussion over the radio with a towboat pilot on the Ohio River about how well he could see me with the factory-installed radar reflector. He said his radar displayed my R27 very well.

CaspersCruiser: That's comforting to know, as RT claims there really is no need for us to add additional radar reflection to our boats. 😀

On the boat now with radar on with gain set to Auto. Lots of boats around and everyone is detected and no false positives except around the big tankers. 😀
Curt

A couple nights ago that the radar alerted me to the towboat, when I activated the radar the gain was set to 90% and the display was a big blob. After reducing gain to 65%, the display was more normal and the towboat popped right up about 1/2 mile ahead as well as a 27' Marinette (aluminum cruiser) 1/4 mile behind. I'm unsure why the gain produced different results than earlier trips. I've got a lot to learn.

I am still in the learning process of interpreting images on the radar. This is our second season with our Cutwater. While I have been boating for a number of years I never had the need for radar for the type of boating we did. I have installed radars on boats for customers and understood the basics but never really navigated with Radar ( boat deliveries are not normally done in the Fog or Dark). So now has we prepare to do some extensive cruising in our boat the importance of understanding the functions and navigating with radar is important. Last season I used the radar while cruising to familiarize myself with what images look like on the radar when I can actually see them thru the windshield. Only twice did I need and use the radar for navigational purpose. I was on the Tennessee river (George Wheeler lake) in a wide section. I was following the magenta line. I couldn't see where the next maker was. I used radar with overlay on the plotter. The radar picked up the marker and I found the magenta line was off approx. 15 degrees to the actually channel. This season as resent as last Saturday I used the radar for navigation on Lake Michigan. We left Racine Harbor Wis. heading south to Waukegan Il. Partly sunny day plenty of boats out , so we headed 5 miles off shore to avoid some of the boat traffic, now south for an 1.5 hours cruising at 7KTS and all at once a fog bank rolled in. Less then 1/4 mile visibility. I didn't know if it was going to get worse further south so I turned and headed back using my active tracks on the plotter and Radar. Unfortunately the fog prompted a number of fishing boats, sail boats and pleasure boats that were out further in the lake to head in. We crossed paths bow and stern. I could see them on the radar. When some of the boats got close enough I did make visual contact. I probably would have made it back to the harbor with out the radar but it gave me an extra layer of safety. Using my active tracks was a plus too. It brought me right back to the harbor. I'm still a novice at electronic navigating but learning! As far as gain level I have mine set at 58%. I can see the difference from break walls and shore , harbor openings seem clearer, And I don't pick up distant clutter. I'm not sure if its the best but so far thats what I'm using .
Brian Brown
Cutwater 26
PORT-A-GEE