Radar reflector

[psneeld]

Though I haven't tried it, I am convinced that if your boat is a poor radar target, the more reflective material the better. Maybe a flybridge fairing lined with foil would be better than the tiny radar reflector that's designed to be stowed easily and cost what the market will bear. Efficiency may not be the only design factor. Or based on West's test no matter what you do a small boat will still be an intermittent target.

But as I have said all along, why not check to see if your boat is an adequate target and not worry about either foil or a reflector. As West said...the only way to be sure the other guy see you is to see him first and let him know if it's becoming an issue.

 

[backinblue]

The reflectors, like Echomaster, are designed to provide a flat reflecting surface from a lot of different angles. A surface lined with foil may provide a perpendicular surface sometimes but at other times could be parallel. Look at navigational buoys and the size of the reflectors on top of some of them. I don't think size of the surface is as important as the angle of it. The reflector I own has rarely been taken apart and I don't consider it tiny or flimsy. It can be taken apart, but I don think that was the main design objective.

 

[psneeld]

The diagram I posted (which showed that I knew enough to look for it) before shows the theory and the actual West test showed the approximate reflective area each reflector mimicked in square meters....when properly aligned.... which was only some of the time in heavy weather. Thus their ultimate recommendations that reflectors are minimally useful.

Believe me I have thought about this for years considering how many different ways I have used and depended upon locating vessels by radar.

 

[backinblue]

The diagram I posted (which showed that I knew enough to look for it) before shows the theory and the actual West test showed the approximate reflective area each reflector mimicked in square meters....when properly aligned.... which was only some of the time in heavy weather. Thus their ultimate recommendations that reflectors are minimally useful.

Believe me I have thought about this for years considering how many different ways I have used and depended upon locating vessels by radar.

No worries, to each is own. IMO if I was worried about being seen by radar (a rare situation for me personally) I would spend the ~$75 for a separate reflector as insurance. That's just me. YMMV. BTW, West Marine is not the bible on boating IMO (sorry for all the abbreviations). They have a few articles and recommendations that are contrary to what other seasoned boaters and experts recommend.

 

[psneeld]

No worries, to each is own. IMO if I was worried about being seen by radar (a rare situation for me personally) I would spend the ~$75 for a separate reflector as insurance. That's just me. YMMV. BTW, West Marine is not the bible on boating IMO (sorry for all the abbreviations). They have a few articles and recommendations that are contrary to what other seasoned boaters and experts recommend.

I personally know one of the West testers and would put him up against any other boating expert (maybe not radar expert).... OK...I will stop now.....

 

[backinblue]

Me too, nuff said, all good!

 

[Hippocampus]

Any body fooled with active(powered) reflectors? If you’re really concerned about this maybe that’s the way to go?

Here’s an example

https://www.plastimo.com/en/reflecteurs-radar-actifs-9747.html

 

[janice142]

The problem with painting a radar reflector black is that it MUST NOT be displayed when underway. Thus for those in inclement conditions having two purpose built items may indeed be a better solution.

For me, the standard plastic folding radar reflector is fine. I do not have a real radar reflector. The one I purchased and painted I gifted to a boating friend who wanted an anchor ball.

As I already owned one, then found a radar reflector, I created one for him. They look the same although the plastic anchor balls do fold flat for easy storage.

In retrospect I could have passed along my plastic one and kept the radar version for self. Such is life.

 

[backinblue]

Any body fooled with active(powered) reflectors? If you’re really concerned about this maybe that’s the way to go?

Here’s an example

https://www.plastimo.com/en/reflecteurs-radar-actifs-9747.html

I don't know how well those work but they are in the $1000 range and require installation and wiring. I finally did read the West Marine article and some other reviews, and the passive Echomaster ball looks to be the highest rated device. Nothing is perfect, but it's cheap insurance if you are concerned. It's $60 from Defender. I'll leave it there.

 

[psneeld]

I am assuming they are radar transponders in some form....cant get much info from a quick search.


Radar transponders work great, but can't say these do.


Some aids to navigation have radar transponders on them and show up great....in busy shipping areas those are the multi short bar pulses one sees occasionally.


a SART is a radar transponder used for SAR and acts like an EPIRB but for radars.


This is a SART picture, I assume the Plastimo would do similar but less bar returns.

 

[Hippocampus]

Beyond racons also have no experience. That’s why I asked. Spec sheet says they don’t draw much and wiring seems simple enough. Agree as long as my buddies say they can see me my pockets aren’t deep enough to justify the expense.

 

[Greg S]

Is it just a Canadian modification of the Collision Regs or what?
Radar reflectors are required by the colregs. Yes, there are exceptions, but I've seen 25 foot aluminum crew boats that didn't show up until within a mile because they were aligned at the wrong angle to reflect back. 14 foot tinners that are invisible until within half a mile for the same reason. Metal on your boat, like a dry stack, railings, and such, are round. Round doesn't reflect back to the source, it bounces the signal every direction but back to the source.
Military radar invisible aircraft have smooth, rounded shapes to deflect radar waves rather than bounce them back to the source, alot like many of the new styles of boats (not trawlers). Doesn't matter if they have large metal tanks or big engines inside if the hull and superstructure are shaped to reflect signals every direction but back at the source.
Colregs (or is this also a Canadian modification) also state the reflector sound be as high as possible but at least 13feet off the water, if that is possible.
So, I want to know how they came up with a weird figure like 13 feet.

70 posts so far and nobody seems to know they are required by the colregs?

 

[psneeld]

Is it just a Canadian modification of the Collision Regs or what?
Radar reflectors are required by the colregs. Yes, there are exceptions, but I've seen 25 foot aluminum crew boats that didn't show up until within a mile because they were aligned at the wrong angle to reflect back. 14 foot tinners that are invisible until within half a mile for the same reason. Metal on your boat, like a dry stack, railings, and such, are round. Round doesn't reflect back to the source, it bounces the signal every direction but back to the source.
Military radar invisible aircraft have smooth, rounded shapes to deflect radar waves rather than bounce them back to the source, alot like many of the new styles of boats (not trawlers). Doesn't matter if they have large metal tanks or big engines inside if the hull and superstructure are shaped to reflect signals every direction but back at the source.
Colregs (or is this also a Canadian modification) also state the reflector sound be as high as possible but at least 13feet off the water, if that is possible.
So, I want to know how they came up with a weird figure like 13 feet.

70 posts so far and nobody seems to know they are required by the colregs?

While true that rounded shapes are usually lousy radar reflectors, enough metal usually works good enough. Can't say that metal boats always are great targets, but my experience has been that they do on a well tuned radar unless lost in clutter.


Radar reflection is not complicated but can be oversimplified. Military stealth aircraft have highly engineered shapes and top secret anti-radar reflective paint to be stealthy.


Reflectors may be required in Canada, but I don't recall where they are universally required (a link would be appreciated).

 

[Greg S]

Reflectors may be required in Canada, but I don't recall where they are universally required (a link would be appreciated).

Yes, Canadian modifications. Rule 40

Not universally required but "where practicable". Not required in daylight conditions with low traffic and good weather. Not required in areas where radar isn't used for navigation.
My take on that is, it is required in most tidal water boating areas on the Salish Sea and connecting waters.

Rule 40 Règle 40

Radar Reflectors

(a) Subject to paragraph (b), a vessel that is less than

20 metres in length or is constructed primarily of non￾metallic materials shall, if practicable, be equipped with

a radar reflector or other means to enable the vessel’s

detection by other vessels navigating by radar at 3 GHz

or 9 GHz.

(b) Paragraph (a) does not apply where

(i) a vessel operates in limited traffic conditions, day￾light, and favourable environmental conditions and

where compliance is not essential for the safety of the

vessel, or

(ii) the small size of the vessel or its operation away

from radar navigation makes compliance impracticable.

 

[psneeld]

Interesting..... probably not a bad Idea but I would love to see why they they made it such a priority to discuss it but the mandate is worded so weakly.