I use a Fenix pd3. Strobe, S.O.S. beacon modes.... as well as many levels of standard flashlight . Low mode walk to and from treestand , lasts forever. Tracking ? bump it up and the woods becomes daylight .

Lost? S.O.S or beacon mode .

Does anybody knows what kind of bulbs that are in the good ole' tried-n-true strobes that have been around for quite some time? What kind of watt ratings are we talking about?

I am thinking those bulbs could be pretty powerful and still conserve batteries because the flash is so short. Don't think in terms of old-fashion incandescent flashlights - LED's surpassed them in most brightness versus battery longevity configurations years ago. But with such a brief but strong flash you could have a very powerful light bulb and still a decent battery life, and with a light output way beyond those nice LED light strobes. Or am I mistaken?


Of course, just recently some super-bright super LED have been manufactured with maximum output roughly equivalent to a set of car high beams. Because of heat issues (LEDs don't like to be warm) there are engineering challenges running those at full steam in a flashlight. Running them in a strobe light should be much easier.

Those are Xenon strobes which require a capacitor to charge up between flashes to get the really bright output. The brighter the strobe, the longer interval between flashes which can work against you, especially on the water.

In testing some really high power xenon strobes, we found the flash rate to be slow enough that at distance it looked like any other deck light on a bobbing boat. That was pretty much the case with the typical 50-70 flash per minute strobe rate. This is especially acute when using night vision goggles because every bobbing boat, buoy, etc. looks like a strobe flashing.

That is one reason the Navy is looking at a strobe rate at about 120 flashes per minute because it's more distinctive in a marine environment. We have had some success with the conspicuity of high power LEDs opposed to the classic xenon strobes. The power management of the LEDs is much better too.

Unfortunately, the best performer is not on the market... yet. But I imagine eventually it will be.

A really good off-the-shelf LED strobe is the VIP Survivor by Adventure Light. It's very conspicuous, has a steady on, steady strobe, and SOS strobe settings.

It's not cheap though. They go for about $180 retail.

Tom

i asked a local sheriff's aviation / sar unit official about this during a presentation two nights ago.
they have and use night vision eye wear. he said they've had lost hikers turn on their cell phones and point it in the direction of the helicopter. he said pilots have seen that illumination from "miles away".

i guess the point seems to be that seemingly little light can attract attention - but just think what a flashlight or dedicated strobe could do for you.

I would agree there are some differences, but not all that much. The strobe unfailingly stands out and provides a good target. And we were not marking LZs, usually we were identifying our location for a hoist operation.

I have never seen a party needing rescue to have anything like adequate signaling gear, often not even flashlights. What did work was ignition of a campfire. If we were alerted to overdue groups and were heading into the general search area, a campfire, alerting us either through seeing the flames or smelling the smoke, made contact very simple and easy. Of course, there are times and situations where you do not ever want to start even a small campfire. More than a few destructive, large scale conflagrations have begun that way.

You can get one here: VIP Survivor at Night-Gear for $120, shipping included. The review of these at Seasteading.org under "Strobe" provides a coupon code they say is good for 10% off.

That still seems like a lot, when US Coast Guard approved Xenon Strobe with 3 mile range can be had for $15. While the VIP's versatility (it also serves as a regular light) would make me consider it for backpacking, and the 100 meter depth rating for diving, there are other choices with that versatility, like the $25 ACR Firefly Plus (albeit that unit has less range and no USCG/SOLAS approval).

I notice that Alan Romania chose the VIP Survivor for his personal small survival kit.

The 2008 VIP Survivor PDF brochure says:

• SOLAS approved May 2008
• 2"x3"x1.35"
• 4 oz
• output is Off/Steady On/SOS/flashing (bevel twist controlled)
• -40 deg F to 150 deg F operating range
• waterproof to 100 meters
• lithium EL 123A 3V battery, (for which a 10 yr shelf life is claimed.)

The 2008 brochure says 2.5 mile visibility, 12+ hour life, but it seems to have been upgraded since to 3+ mile range and 20+ hour battery life, per the spec sheet on the current web site. I wondered if the apparent increase in brightness and battery life was due to an LED upgrade. After searching around, I found that the Seasteading Strobe review indicates that was the case.

My first thought was that I'd add some spare batteries, and I see they recommend that too.

I looked at the VIP LED strobe line on the Adventure Lights Web Site. The model differences seem to be whether you want the lifejacket/raft size, black or yellow, and, for the lifejacket size, whether you want the control to be (manual/pull pin/water activated) for list ($130/$180/$210). The web site has a side bar with more information (applications/specifications/instructions/brochure/warranty)

Adventure Lights also has some pretty exotic variants of this unit for military use, including versions with multisource IR/Green/White light, programming for changing light signatures, intensities and IFF identification, a "Mockingbird (TM)" feature that will memorize another IR source, and a target warning feature that reacts detects a targeting laser, illuminator or high output IR light source.

When I checked the Adventure Light website, it stated a 5+ mile visibility.

In our tests, we were able to see the VIP survivor at a little over 6 miles from an aircraft. It's a pretty rugged product and will stand up to abuse better than a Xenon bulb (FireFly) type. But getting the FireFly with lesser range is better than not getting any strobe at all. The VIP Survivor's longer range will have better effect for marine where use on land will mitigate some of its range due to obstructions from terrain and foliage.

Tom

Quite right - the current main description says "it can be seen for over five miles" and the current spec page I linked to in my post says "Over 3 miles (5 km) over land and over 6 miles air". Since the spec page seemed more detailed, I cited the low end number and provided the hyperlink.



That's good to know - you definitely have me thinking about upgrading from my current strobe. Was that with unaided vision? What altitude? How did that compare to your results with the other units?

It seems that USCG/SOLAS approved life jacket strobes are expected to be visible for at least ~2 nautical miles from the air: Table G-17 of the National SAR Supplement [1] and Table H-24 of the USCG addendum [2] both call out a 4.4 NM estimated visual sweep width when searching by helicopter for a 50,000 peak candlepower life jacket white strobe if time on task is < 1 hr, and 3.9 NM if time on task is > 1 hour. If I have it right, the visual sweep width is the track-track spacing of your search grid, which would imply the USCG expects to see such a strobe at a range of at least half the sweep width, or 3.9 miles/2 = ~2 miles.

The USCG tables also address much dimmer strobes - listing a 0.5 NM estimated sweep width for a 2,000 candlepower peak strobe at night - a pretty damning assessment, considering that they cite a 1.0 NM estimated sweep width for a "Cyalume personnel marker light" (glowstick). ( The cited references and lots more are available at this link: USCG SAR Manuals and Documents Page ).

[1] United States National Search and Rescue Supplement
to the International Aeronautical and Maritime Search and Rescue Manual, May 2000. Available on the USCG web site at:
http://www.uscg.mil/hq/cg5/cg534/manuals/Natl_SAR_Supp.pdf

[2] COMDTINST M16130.2E: U. S. COAST GUARD ADDENDUM TO THE UNITED STATES NATIONAL SEARCH AND RESCUE SUPPLEMENT (NSS) To The International Aeronautical and Maritime Search and Rescue Manual (IAMSAR) Sept. 2009. Available on the USCG web site at:
http://www.uscg.mil/directives/cim/16000-16999/CIM_16130_2E.pdf

I think you have the right idea. While the power of a xenon strobe is an advantage the fragile flash tube, battery life, and overall unit bulk and weight make such a unit a burden.

At night in a wilderness area a small blinking light can be seen for miles. Something small and light like a Pelican 2130 Mini Flasher LED Submersible Clip-On might be more practical:
http://www.opticsplanet.net/pelican-mini-flasher-2130-led-flashlight.html

Tiny and less than a third of an ounce each, including batteries, you can carry two. Run time is reported at 130 hours, better than five days. Hoist one high into a tree, or on an exposed ridge line, with a note telling people which way you're heading and use the second at night to advertise your position. The one you leave behind is cheap enough, under $10, to be expendable in an emergency.

A pretty good little light that is compact enough to have with you is better than a really good one left at home.

At this point I will display once again my dinosaur like devotion to the good old zenon strobe. Mine go back to when computers ran on punch cards. I found them neither fragile, or heavy, and the battery in my oldest is still working, and it is at least ten years old (hasn't been deployed much lately, though). My newer ones rode in my PFD for years in a salt water environment and were problem free.

I like them because they did their job, every time, and they were always handy.

I use bike blinkies a lot (I am a regular bike commuter), but I don't think they are comparable to a powerful strobe, nor do I think they would attract attention as much as a strobe, or, for that matter, a good campfire. I regularly run at least two blinkies so that motorists won't ride up my back.

As always, you pick your gear and equipment judiciously for the task at hand, balancing weight and bulk against the possibility of use (big FAK vs. two bandaids; shoelaces vs 60M climbing rope). There are plenty of options out there.