When To Use a RADAR Reflector?

[Cynara]

We had ours hung in the spreaders whenever at sea. I can't imagine when you wouldn't

[CyKlop]

Originally Posted by thomm225

Some radar reflectors are better than others, but I think the Echomax Active XS
is the best.

It even alerts you when your boat is "painted" by radar.

https://www.datrex.com/product/echom...proof-control/

Note that one is not, technically, a radar reflector. Rather, it re-broadcasts the signal. For purposes of painting a bigger target on someone's radar screen, it's probably superior to most reflectors out there, but it has the drawback of requiring a power supply... 23 mA in standby, 360 mA when active. Depending on how busy your area is, it might be active a fair bit.

Admittedly, even 360mA isn't very much, but a milliamp here, a milliamp there, sooner or later it adds up...

[philiosophy]

· I worked offshore rugs for 36 years. Predominately on the West Coast of North America. Many time we would be running North hugging the coast to get out of the Summertime North West winds. A number of times we encountered the Santa Cruz to Ensanada Race. We would get intermittent and very weak return from what was described by those in the race as "the latest in Radar Deflector technology. The only way we missed these sailboats was by getting their position and course and navigating away from them based on that info. I imagine an active system would be effective but real life experience with modern commercial radars operated by professionals tell a different story than testing where they know the reflectorI/deflector is in a known location.

"It isrecommended that poorly performing radar reflectors are not fitted as it
is possible that the user could be lulled into a false sense of security believing
that their chances of detection has been enhanced."

The paragraph above is the last one in the summary of results after testing the various systems and passive refector/deflectors. That is I believe the truth.

[Mare Nostrum]

We use the "old school type"...it works well every time...when we're on the high seas, each night, nearby ships confirm that they "see"us...

[David Rainbow]

We were on a Coastal Trading Vessel job heading up the coast of Western Australia one time and kept on passing a Yacht that painted a really strong signal
on our radar display. Later one of the crew caught up with the sailor and asked why his vessel reflected so well. Answer, He had stuffed aluminium foil down his mast. Not sure how long it would last and what the thickness of the foil was but it certainly did the job well.

[AndyEss]

Originally Posted by David Rainbow

We were on a Coastal Trading Vessel job heading up the coast of Western Australia one time and kept on passing a Yacht that painted a really strong signal
on our radar display. Later one of the crew caught up with the sailor and asked why his vessel reflected so well. Answer, He had stuffed aluminium foil down his mast. Not sure how long it would last and what the thickness of the foil was but it certainly did the job well.

Just how is that different from just having an aluminum mast?

[Adelie]

When a radar paints an aluminum mast it usually gets a return from the vertical sliver of the radius that is facing straight back as the Radar.

With a wood mast full of crumpled up aluminum foil there will be a lot of randomly oriented retroreflectors. Net are of the random retroreflectors is a LOT bigger than the sliver of the mast that returns signal and it sounds like more than your typical radar reflector.

[AndyEss]

Originally Posted by Adelie

When a radar paints an aluminum mast it usually gets a return from the vertical sliver of the radius that is facing straight back as the Radar.

With a wood mast full of crumpled up aluminum foil there will be a lot of randomly oriented retroreflectors. Net are of the random retroreflectors is a LOT bigger than the sliver of the mast that returns signal and it sounds like more than your typical radar reflector.

I agree for a hollow wood mast, crumpling up aluminium foil and stuffing the hollow would improve its radar reflectivity substantially, but this would do nothing for an aluminum mast. A hollow mast stuffed with aluminum foil would also play hell with internal halyards and electrical wiring.

[David Rainbow]

I was thinking about installing a few of those rectangular radar reflectors to the top and bottom of my lower spreaders horizontally to the mast of course. Having been at the other end and picking out weak signals in which to avoid I consider reflectors quite useful. Years ago I drove a Sydney Harbour cruise boat and often came across racing buoys left in place from the day before. Luckily these buoys had reflectors that even painted a good target on a very basic radar. My mast is Aluminium by the way but I have driven boats with composite and timber masts as well. As to the yacht we were following mentioned previously, I seem to recall it being a timber mast. Wires shorting internally shouldn't be an issue unless those circuits were incorrectly installed in the first place.

[Lodesman]

Originally Posted by Adelie

When a radar paints an aluminum mast it usually gets a return from the vertical sliver of the radius that is facing straight back as the Radar.

With a wood mast full of crumpled up aluminum foil there will be a lot of randomly oriented retroreflectors. Net are of the random retroreflectors is a LOT bigger than the sliver of the mast that returns signal and it sounds like more than your typical radar reflector.

I seriously doubt crumpled aluminum foil makes a good radar reflector. The wavelength for X-band radars is 2.5-4 cm, so I think the reflective surface would need to be at least that size for there to be a return. I'm not a radar engineer, so if I'm mistaken, I'm happy to be corrected.

Timber masts typically have a number of metal bands and other fittings, that might have provided good radar return.

[Lodesman]

Originally Posted by philiosophy

·
"It isrecommended that poorly performing radar reflectors are not fitted as it
is possible that the user could be lulled into a false sense of security believing
that their chances of detection has been enhanced."

The paragraph above is the last one in the summary of results after testing the various systems and passive refector/deflectors. That is I believe the truth.

That really is poor advice. The passive radar reflectors, like most marine devices, have limitations. Any mariner worth his/her salt should understand the limitations of the equipment they use. It is then unlikely, they should be lulled into a false sense of security. While I think an active transponder in both X and S band is the better choice, if and when I get one, I'll still use the passive reflectors that I have up now. Electrical things lose power. Wires chafe, water intrudes, lightning strikes - however it happens, it only makes sense to keep a back-up that is not dependent on power.

One of the major limitations of the spherical trihedral designs is the deep nulls at the cardinal points of the device. I've never seen it mentioned, but I think it would be fairly simple to mount 2 of them vertically such that the azimuth of one is skewed 45º from the other. This would ensure the deep nulls from one would be covered by the peaks of the other. If you used 4 of the devices you could have 2 in catch rain, and 2 in double catch rain skewed as above, to ensure comprehensive coverage. That's still pretty cheap insurance.

[Jamme]

Originally Posted by Boatyarddog

Half that price thru Defender.com
$899.00.. (First time sale price $839.00+ shipping)
That's some great insurance.
https://www.defender.com/product.jsp?id=2025484
SV Cloud Duster

Just for clarity, I think there are two models out there, one (more expensive) that uses both X and S bands; and another (cheaper) that only uses X band for coastal navigation.

The one above is the cheaper model.

[goboatingnow]

Originally Posted by Lodesman

Did you confirm the band used?

I can’t remember but I seen to remember he had both radars running for me

[goboatingnow]

Originally Posted by wingssail

What you just said is exactly in line with my experience on radar equiped boats: It takes some training and experience to get the most out of radar, and even then constant attention and interpretation is needed. The automatic settings don't seem to be as good as a skilled operator.



So that brings us to the problem: Since I don't carry a radar operator or extra skilled watch stander, radar operation is not really how I wish to spend my passage time. I think "eyes out of the boat" is better use of my and mate's time.



And then there is the electrical use that radar has, AND, for my boat, where do I put a radar console? I don't even have a chart plotter on deck.

I found radar extremely reassuring on longer overnight voyages especially in or near shipping activity. The auto settings on most modern settings are very good. ( I’m an ex RYA radar instructor )

[Jetx]

I agree with boatpoker.. too many boats still out there without AIS. I wouldn’t move along the E coast at night, or in the fog in Maine, without radar. Thankfully all of the lobster boats have a reflector mounted.

We traveled in the company of three other boats for about a month this summer. One had a cheap Davis octahedral reflector hung just below the spreaders, the other two had no reflector. I could pick up the boat with the reflector at all times out to 5 miles or so. The other two, I could rarely see on radar if they were more than about 1/4 mile out (I had them on AIS, so knew where they were, but did not get any radar return). This is with a new generation Raymarine Quantum radar.