These are my stories as a volunteer member of the Sheriff's Search & Rescue team in Coconino County, Arizona. I'll share what it's like to go from a beginner with a lot to learn to an experienced and, hopefully, valuable member of the team, as well as the missions, trainings, and other activities along the way.
About Coconino County
About Coconino County
Encompassing 18,661 square miles, Coconino County, Arizona, is the second largest county in the U.S. but one of the least populated. Our county includes Grand Canyon National Park, the Navajo, Havasupai, Hualapai and Hopi Indian Reservations, and the largest contiguous ponderosa pine forest in the world. Elevations range from 2,000 feet above sea level along the Colorado River to 12,633 feet at the summit of Mt. Humphreys in Flagstaff.
November 8, 2008
PLBs and Plenty of Zzz's
It turned out to be a good drill, basically. Several of us proceeded to load tech gear, ATVs, the Ranger UTV, cubes of water, MREs and snacks, and full gas cans, then drove for about fifteen minutes before the mission was 10-22'd. The woodcutters had been located near Peach Springs. So we did an about-face, returned to the SAR building and unloaded all the gear. And that's been about it over the past couple of weeks. I've had way too many full nights of sleep. I'm thinkin' something will happen soon.
Oh, and we did have another cancelled call-out on the afternoon of Saturday, October 25th, just as we were finishing up a rather frustrating PLB training. (I'll get back to that in a sec.) It sounded like a pretty dire call at that. A girl--not sure if it was an adult or child--had supposedly been attacked by bees about four miles up the West Fork of Oak Creek, and she was having an anaphylactic reaction. It was definitely going to be a tough litter-carry, possibly involving some wading in places where the creek fills the canyon. And word through the grapevine was that first responders (not sure if that meant medics, deputies or civilians) were already "working a code." So we were thinking this might end up being one very rugged body recovery by the sound of things.
On my way across town to the SAR building, though, the mission was cancelled. At the time, I thought perhaps the girl had been short-hauled, since it was apparently very serious. But I later found out she'd been given Epinephrine and walked out on her own. Glad to hear that!
So back to the PLB training. "PLB" stands for Personal Locator Beacon. To read specifics about this and other types of devices used to transmit distress signals, you can visit the Search and Rescue Satellite-Aided Tracking, or SARSAT, website. As for me, I refer to the thing that emits the distress signal as a "gadget," and the device responders use to track down the gadget (and hopefully the person/s needing help) as a "gizmo." Gadget and gizmo ... got it?
So first we had a classroom session. We learned about the different types of beacons--PLBs used for land-based applications, ELTs for aviation use, and EPIRBS for maritime use--and the basics of how they work. Seemed pretty straight-forward at that point.
Then we went out behind the Sheriff's office, where Sergeant D turned on the training PLB gadget, and we walked a couple hundred yards across the parking lot where we used the gizmo to locate the gadget. Of course, we could see the gadget from where we were standing with the gizmo. Straight line, no obstacles, flat terrain. I understood how it worked and figured, hey, this is easy!
And then it was time to take the gadget and gizmo into the field. We relocated to Fort Tuthill, where the plan was to take turns going off into the woods with the gadget with about a ten-minute head start, and then the rest of the group would use the gizmo to located the source of the distress signal.
Well, the first time out, things went fine. Trees, yeah, but pretty flat. Now, the gizmo, by the way, makes a continuous, rather annoying sound--a constant, high-pitched, whiny beep--which the responders have to listen to the whole time they're searching. This first trial didn't take us all that long, so none of us mentioned anything about stomping on the thing. Second time around, though--different story.
We were all over the place, with me using the gizmo for maybe the first hour. At least, it seemed that long. But the thing couldn't seem to make up its gizmo mind. I was getting conflicting signals, first this way and now that. We were now in hilly terrain with lots of rocks and other obstacles, and I guess the signal was bouncing all over the place.
Eventually, I held the whining gizmo out to Sergeant D and asked (trying not to sound desperate), "Do you wanna try?" thinking at that point that I must be doing something wrong. I'm not sure what our leader was thinking, but he wasn't saying much as the rest of us followed him follow the gizmo.
A few members of our team, who'd been using the low-tech method of detecting a PLB signal with a radio set to a certain frequency and a body shield (if you really want an explanation, feel free to let me know in the blog comments and I'll give it my best try) had disappeared. I hadn't noticed they'd walked off, leaving just me and another lady following Sergeant D. I looked around and didn't see them anywhere.
Eventually, Sergeant D radioed the others, and we learned they'd found the guy with the gadget a long time ago. What! The gizmo had failed us while the low-tech method had worked? When I saw where the guy with the gadget had been the whole time, I realized we'd passed pretty close to his location early on in the search. Ugh.
So, then Sergeant D took the low-tech method out of the equation, grabbed the gadget, wished the rest of us luck, and took off to hide. Basically, the gizmo took us in a huge circle, leading us to think Sergeant D was on the move with the thing the whole time. So a moving distress signal, right? We even thought, based on the signals we were getting, that he'd gone back to the vehicles. But, when we got there, not only was there no sign of Sergeant D, but the gizmo was registering no signal at all. Nada. Dead.
Frustrated, we called Sergeant D on the radio, and he gave us some coordinates. We used our GPS's to go to those coordinates, thinking we were looking for him and/or the gadget, but we soon realized he'd gotten us fairly close but not to the spot. He continued to give us hints, we continued to try to follow the directions the gizmo seemed to be leading us in, but we wandered all over the place with no luck. Finally, thankfully, Sergeant D called the thing off. We'd apparently walked right by him more than once.
Was it the hills and obstacles interfering, making the signal bounce all over? Or was it us, the searchers using the gizmo? What I do know is that I was hearing that whiny beep in my dreams for several nights thereafter.
12/12/08 Update: Check out an interesting conversation about PLBs and the SPOT device on backpacker.com's forums: Click here.
First, let me apologize for butting into your blog... Second, let me disclose that I work for a large PLB and RDF manufacturer. Tell me to go away and I will.
The frustrating experience you describe isn't uncommon. However, I frequently locate beacons hidden in mountainous terrain, in snow, in the Everglades, etc. within minutes. An average location covering 2-miles or less takes about 25 minutes. Few have taken an hour, and those involved very difficult terrain. I believe that with a few minutes of effective instruction in the use of your RDF you could find a beacon in minutes too. I'm located in Florida, but would do a clinic with your SAR group next time I'm in the neighborhood. If you are interested, post a response and I'll send you my contact info.
You're not butting it in at all! In fact, I welcome your comments any time. And I'd definitely like to give PLBs another try. I don't like to give up when things don't go smoothely. In fact, that makes me want to figure it out even more so.
We haven't had many occasions to use the technology in the field, as far as Coconino SAR is concerned, and none since I've been on the team, but I'd like to be prepared if and when it happens. I do recall there was a man in distress somewhere on the north rim of the Grand Canyon who used a PLB within the past couple of years.
Anyhow, I'll definitely pass the info about a possible clinic on to the Sergeant in charge of our unit. If you actually do happen to plan a pass through our area, let me know. (firstname.lastname@example.org)
Thanks again for your comment and offer. I hope to figure out where we were going wrong (or perhaps if there was an issue with the equipment?) during the training. As mentioned, early on it seemed to work just fine, but perhaps it was simply user error as time went on. I hope I haven't discouraged anyone from using the technology (not that I have that sort of influence!), because I know very well these beacons have save many lives.
I'll contact you via e-mail when I'm next heading your way.
By the way, I don't think there was anything wrong with the PLB or transmitter in your test. There were two issues: one was with understanding the indications provided by the RDF relative to the terrain. Terrain has a tremendous impact on the signal direction due to reflections and multi-pathing.
The second is the nature of the signal, or electromagnetic energy, itself. Think of a magnetic field with a positive and negative pole and file shavings forming themselves into semi-circles or waves on either side of the magnet... With an RDF you are following those waves... You are not following a straight line to the source.
Once you understand the shape and learn to interpret the impact of terrain on the signal it becomes fairly easy to get within a few meters of the transmitter...
A PLB serves two functions. 1. Global alerting and general location. Within minutes the AFRCC can know who you are, roughly where you are and that you are in trouble. 2. Local homing signal on 121.5 MHz. The homing signal is there to lead local SAR to the victim’s location if the Doppler derived coordinates or the internal GPS provided coordinates don't put SAR directly on top of the victim.
There are a couple of issues that Local SAR should be ready to handle when they receive their first PLB Alert Message. The AFRCC will send an "Alert Message" with the coordinates expressed as Degrees and Minutes to the thousandth decimal place. You will need to be prepared, (not difficult), to convert this to a Lat/Long expression you are more comfortable using within your SAR unit...Degrees, Minutes, Seconds for example.
If you are prepared to handle the information provided by the AFRCC and are trained with RDF equipment, you will find PLBs an absolute snap to locate.
I hope to meet you someday soon.
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