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Electronic Visual Distress Signals

What type is best for your boat? Here’s a look at two.

In 2015, I tested the first electronic distress signal that could effectively and legally replace the flares that the U.S. Coast Guard requires on most of our boats. Hot flares always struck me as a dangerous way to seek help. They are distinctly unpopular with the folks who protect our environment, and their short lifespan is a hassle.

Orion LED distress optics compared to Sirius Signal design

Orion LED distress optics compared to Sirius Signal design

Now, that original SOS C-1001 LED flare—designed and engineered by Sirius Signal and currently distributed by Weems & Plath—has competition from Orion Safety, which manufactures most marine pyrotechnic flares. It’s good news, I think, that Orion has endorsed the electronic Visual Distress Signal Device (eVDSD). Now, boat owners have more choices.

What type is best for your boat? I did a comparison of the two SOS distress signals, each of which retails for about $90.

The slightly larger Orion opens only at the bottom and is powered by two D-cell batteries, while the Sirius Signal can be entirely dissembled from the top and uses three C-size batteries. Those features are important because a significant drawback of an electronic nonpyrotechnic device is that it uses batteries that can leak, corrode or fail. If a battery did corrode inside the Sirius Signal design, you could access every part for cleaning. In fact, according to Sirius, you can purchase any part that needs replacement. Also, Sirius includes a platinum catalyst that’s meant to protect against the outgassing of a failing alkaline battery. It’s a nice feature.

I also like Sirius’ careful engineering of the on/off switch and power path, always potential points of failure, especially for equipment that is rarely used. The one-piece copper battery spring and negative power conductor fit into the Sirius case so that its springy tip can engage the aluminum contact area on the back of the electronics cup when you screw the lens down a couple of turns. There’s a large copper positive contact on the cup, and all conducting contact surfaces are self-cleaning with the twisting motion. Moreover, the Sirius is arguably easier on the switching path than the Orion because it uses 4.5 volts instead of 3 volts to produce the same mandated light intensity levels, and thus less current.

Orion SOS distress light broken apart

Orion SOS distress light broken apart

By contrast, the Orion SOS Beacon had to be pried apart so that I could examine the innards. The sealed air volume—with the double O-ring battery cap in place—and the larger size do give this beacon more buoyancy than Sirius’ combination of a foam flotation collar and sealed air. The Orion also can be turned on with one hand. However, if that switch fails or a leaky battery fouls up the power path, you might have a tough time diagnosing the problem, let alone fixing it.

To test the two systems, I took both out on Maine’s Penobscot Bay aboard my 37-foot Duffy lobster yacht, Gizmo, for a twilight cruise in late April with my old buddy Alden Cole. We attached each light to a life jacket to make them easier to pick up, and then we floated them down the bay.

This type of testing can be tricky, but neither of us detected significant differences in performance. Both lights float and flash Morse code SOS.

The Sirius Signal design did seem to float a little lower in the water, which could make it a bit less visible, but the unit could have been obscured by the life jacket. Since our test, Sirius Signal tells me, the unit has been modified to float a little higher.

The replaceable parts in a Sirius Signal SOS distress signal

The replaceable parts in a Sirius Signal SOS distress signal

The units appeared to be equally bright and consistent, even from a half mile away, which was the maximum distance we allowed for the test. We did wonder how visible these beacons would be if there were lots of shore lights in the background, but this past December, the Coast Guard issued a policy letter accepting red-orange and cyan as official colors to be used in maritime eVDSDs. A visual distress signal with these two distinct colors flashing SOS can be more effective than the old standard.

Sirius Signal SOS distress light switch detail

Sirius Signal SOS distress light switch detail

Following the test, I concluded that the Sirius Signal design would be preferable, for my needs at least. Its single-handed switching and slightly higher float position are strong features, to be sure, but they don’t strike me as major factors when I envision all the ways an eVDSD might be used in a real distress situation.

Reliability does strike me as being of key importance, and I’m impressed with how well Sirius engineers reliability into this unit. Nevertheless, I’m pleased that eVDSD technology is now becoming mainstream, so much so that a major U.S. flare company such as Orion is on board. 



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