The only part of a fiberglass sailboat that can give a solid RADAR return is the engine block, which is sitting at water level.
Where is your radar reflector?
- Thread starter rpwillia
- Start date
Here is an interesting report on the importance of mounting your radar reflector, the report is from 1995 but I'd imagine still valid: http://www.ussailing.org/wp-content/uploads/DARoot/Offshore/SAS Studies/radar reflector tests.pdf
On our last trip to Tonga from NZ. There were several instances where we knew there was a ship nearby (ie within 20 miles) yet our AIS did not pick them up. Other yachts near us also could not pick them up. So AIS is good but not infallible.
We use a large plastic plumbing tube stuffed with aluminium foil. Capped. And we have them on the spreaders just in case. But time and again we see a boat but they do not respond to VHF calling. Presumably asleep on watch on autopilot??
We use a large plastic plumbing tube stuffed with aluminium foil. Capped. And we have them on the spreaders just in case. But time and again we see a boat but they do not respond to VHF calling. Presumably asleep on watch on autopilot??
Good words Gunni. Common sense seems not to be so common in today’s environment.
It is good this nearly 4 year old message is being revived. Fog has a way of bringing out these concerns about visibility. suspect the season is coming for the NE Coast.
Funny @Skipper.
I am of the trend to have all the tools that can help. AIS, radar, and a radar reflector. In my May 2017 adventure none of it helped. The boat did not have AIS. The radar signature was too small and the speed of the fishing boat did not yield a good track able reflection (30 plus mph in fog 50-100 yards visibility). The boats surface was all metal and side on would have made for a good reflection. Head on the sharp angles deflected signal angularly away from the boat.
It is good this nearly 4 year old message is being revived. Fog has a way of bringing out these concerns about visibility. suspect the season is coming for the NE Coast.
I have heard that the NJ laws are sometimes onerous but I have never heard this. Can you please provide supporting info on this absurd requirement. There is nothing of the sort in the CG regs. While the use of radar is encouraged the CG recognizes it is not just the quality of the radar equipment but also the experience of the user to interpret the information. So such a regulation would be pretty much a useless exercise.
Funny @Skipper.
I am of the trend to have all the tools that can help. AIS, radar, and a radar reflector. In my May 2017 adventure none of it helped. The boat did not have AIS. The radar signature was too small and the speed of the fishing boat did not yield a good track able reflection (30 plus mph in fog 50-100 yards visibility). The boats surface was all metal and side on would have made for a good reflection. Head on the sharp angles deflected signal angularly away from the boat.
Indeed the USCG is wordy and confusing on the issue. The net is that you don't need to have it on, unless you get in a collision. Then you did.
The course was given at Winters Marina in NJ. This is what the instructor told us and others in the class said the same thing. The instructor did not give us any literature so I can not source his comments.
https://www.winterssailing.com/
Like I said, the wording here is not clear, and the laws are complex. Sometimes instructors will 'dumb down' explanations, usually to keep THEM out of hot water. If I had to go on record as how to use it, I would say 'have it on and manned all the time' as well. FYI the USCG tries to explain it like this.
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.
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@Jackdaw The reg you are identifying is for vessels greater than 1600 Gross Tonnage.
The application of this regulation is not for a sailboat in the sizes that most SBO sailors use in the 4 to 20 gross tonnage category. Further the regs have specific standards attached regarding the location and capabilities for the radar equipment. ( RTCM Paper 71-95/SC112-STD, RTCM Recommended Standards for Marine Radar Equipment Installed on Ships of Less Than 300 Tons Gross Tonnage, Version 1.1, October 10, 1995,) Among these standards is the radar antenna be located at a minimum height of 15 meters above sea level. On some of the boats they would need to extend their masts just to be able to comply.
Would you be challenged if you are not using the radar and there is a collision? Yes, the investigator of the accident in all likely hood would be thorough. If in the USCG's area of authority, it could be an issue that you might need to explain.
The question was about the legality of a stated NJ requirement for a pleasure sailboat. Here I asked the poster to provide information.
The application of this regulation is not for a sailboat in the sizes that most SBO sailors use in the 4 to 20 gross tonnage category. Further the regs have specific standards attached regarding the location and capabilities for the radar equipment. ( RTCM Paper 71-95/SC112-STD, RTCM Recommended Standards for Marine Radar Equipment Installed on Ships of Less Than 300 Tons Gross Tonnage, Version 1.1, October 10, 1995,) Among these standards is the radar antenna be located at a minimum height of 15 meters above sea level. On some of the boats they would need to extend their masts just to be able to comply.
Would you be challenged if you are not using the radar and there is a collision? Yes, the investigator of the accident in all likely hood would be thorough. If in the USCG's area of authority, it could be an issue that you might need to explain.
The question was about the legality of a stated NJ requirement for a pleasure sailboat. Here I asked the poster to provide information.
Interesting are you sure? I thought that a RADAR installation was REQUIRED for vessel above that GT, but in any case needed to be made 'proper use' of on any vessel that was RADAR equipped.
I understand your original question to the other poster.
We have a Lensref mounted on the forward side of the mast and protected by a SS "hoop" from lines and the sales snagging it.
The Davis is effective; however you need to secure it to keep it from spinning. We had one, long ago on our Pearson 35. When we hoisted it, in a strong winds one day, it came crashing down on the deck when it spun-around and "cut" the line that held it up. Aside from appearance issues, windage, and chaffing -- the only other concern with the Davis unit is that if you're climbing the mast, you have to be more careful when getting hauled-up or or coming down. ;^)))
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As I understand, PART 164—NAVIGATION SAFETY REGULATIONS which are the applicable Federal regulations used by the USCG have in 164.01 the applicability of the regulation. Here they identify the vessel size standard to which the regs apply.
That rule is ONLY for boats over 1600 GT. For EVERY vessel afloat Rule 7 of both the COLREGS and Inland Waterway Rules says this:
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.
My comments above are in respect to the definition of 'proper use'.
https://forums.sailboatowners.com/i...ur-radar-reflector.162094/page-3#post-1427096
https://forums.sailboatowners.com/i...ur-radar-reflector.162094/page-3#post-1427104
Not to hijack or redirect the thread, but consider this picture and what appears to be a little tiny device, and just how little it really is when it's a mile or more away. Having seen some of the displays on BCFerries, they can detect something as small as driftwood, (as long as it reflects) but their statement was that a reflection is only a starting point. You still need to confirm that it's not an orca playing with tinfoil.
(and that's what the guy said to me)
I have a hard time imaging this working. RADAR reflectors need to be able to re-direct RADAR energy exactly back from whence it came, which requires an exact 90 degree angle. What you describe sounds more like the F-117 'stealth' fighter, which was designed with facet angles where none of them were 90 degrees.
Not all Radars are the same. Vessel Radar technology is growing fast. Not all vessels have Radar.
_______
Personal Notes...
1) Cargo Vessels, barges, and large yachts that I have contacted by VHF [≈30] have seen my boat on their Radar.
2) I have no radar reflector.
3) My Raymarine Digital Radar 2016 is property mounted per OEM at ≈30' above sea level.
4) I have detected kayaks at 3 nm, light seas.
5) My Radar display shows who and what is emitting a radar signal.
6) My Radar will detect/alarm even the slightest movements of targets within a "Guard Zone", while at anchor.
7) It will detect a flock of seagulls feeding on shrimp at 10+ nm.
8) Small high speed craft fade in and out of detection but still remain on MARPA tracking.
______
The newest multifrequency digital radar combined with CHIRP Sonar can image partially submerged objects.
_____
Fog or low vision.
1) AIS
2) Fog horns
3) Ships bells
4) IR vision and detection
5) VHF radio
6) Beam lights
7) A weather deck watch.
8) Safe Anchorage.
Jim...
PS: Boat insurance and PFD's
_______
Personal Notes...
1) Cargo Vessels, barges, and large yachts that I have contacted by VHF [≈30] have seen my boat on their Radar.
2) I have no radar reflector.
3) My Raymarine Digital Radar 2016 is property mounted per OEM at ≈30' above sea level.
4) I have detected kayaks at 3 nm, light seas.
5) My Radar display shows who and what is emitting a radar signal.
6) My Radar will detect/alarm even the slightest movements of targets within a "Guard Zone", while at anchor.
7) It will detect a flock of seagulls feeding on shrimp at 10+ nm.
8) Small high speed craft fade in and out of detection but still remain on MARPA tracking.
______
The newest multifrequency digital radar combined with CHIRP Sonar can image partially submerged objects.
_____
Fog or low vision.
1) AIS
2) Fog horns
3) Ships bells
4) IR vision and detection
5) VHF radio
6) Beam lights
7) A weather deck watch.
8) Safe Anchorage.
Jim...
PS: Boat insurance and PFD's
Aluminium foil was used quite extensively during WW2 to confuse enemy radar. Was called "chaf". Not sure if it still works or not. I have 2 Radar reflectors up at all times. One on the backstay, one in the spreaders. The one on the spreader says mount in the "stags". Still not sure where that is.
Yeah, we see them doing that all the time down at East Point.
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We have a trilens (same one the USN uses on the subs when they want to be seen) mounted just above the spreaders. Based on our club testing it works really well; the davis and the echomax also work well, far better than the plastimos that were delivered on Escape. I agree with Mainesail - AIS is a useful adjunct, but it shows transponders, not what's physically on the water - I've also seen tows on radar and only confirmed by hailing the tug (AIS identified). Until all vessels have transponders, radar is much more reliable - and it's much faster than the class B transponders for updates. In Casco Bay (ME) smaller commercial fishing boats (like lobstermen) and ferries (go figure!) don't have AIS and the lobstermen will resist - they don't want to reveal their position.
I am glad to see this thread is still going after all this time. I like the ideas here about using radar, reflectors and AIS as they are all complementary. FWIW I just helped a friend integrate his Standard Horizon 2200 to his new Garmin Chartplotter via NMEA 0183. Worked very well and picked up all the boats in their slips nearby transmitting (it was about 10 degrees with ice everywhere so no traffic nearby on the bay).