Let people know (where you're going)

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bheiser1
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Re: Let people know

Post by bheiser1 »

AlmostThere, thanks for that post. It made for very interesting and thought provoking reading. In particular the suggestion about leaving "additional identifying info" seems like a good idea. I already do that to some extent, but will do more.

As others have posted, it can be difficult to leave a detailed itinerary, partly because we may want to make decisions on the fly, "oh, this route looks more interesting, I'll try that one", and partly because of the permit issue. For example last summer I headed for Yosemite, on a Saturday afternoon, to go "wherever I could still find a permit to go". As you all know, there's no cell reception in most of Yosemite, so I didn't have any way to advise my people of my final permitted plans.

What I do now, however, is carry a GPS unit with an accompanying SPOT transmitter. I enable tracking while on the move, so my "interested parties" will know my "last known position" at any given point. I also send text messages via the SPOT transmitter at key points on my journey. I totally understand this isn't failsafe. I don't "depend on it", and I don't do anything while carrying it that I wouldn't do if I didn't have it with me. I realize that sometimes messages don't go out, I could drop the unit into a roaring river, etc, etc, etc... But at least it will "probably" work :). And it's better than if I went on such a trip (as above) without anything... and assuming it works, it's better than pre-notification, because it provides near-real-time updates.

I'm totally on board with leaving detailed directions as much as possible, and do so myself. And in fact now I'll add more details to what I provide. But recognizing that this isn't always possible, I am wondering what you, as a SAR person, think of the "electronic" approach. Wouldn't you be glad to be handed the last known GPS coordinates of the target of your search?

Thanks again for posting. It's definitely interesting to read from someone who actually does this stuff (SAR).
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AlmostThere
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Re: Let people know

Post by AlmostThere »

bheiser1 wrote:AlmostThere, thanks for that post. It made for very interesting and thought provoking reading. In particular the suggestion about leaving "additional identifying info" seems like a good idea. I already do that to some extent, but will do more.

As others have posted, it can be difficult to leave a detailed itinerary, partly because we may want to make decisions on the fly, "oh, this route looks more interesting, I'll try that one", and partly because of the permit issue. For example last summer I headed for Yosemite, on a Saturday afternoon, to go "wherever I could still find a permit to go". As you all know, there's no cell reception in most of Yosemite, so I didn't have any way to advise my people of my final permitted plans.

....

I'm totally on board with leaving detailed directions as much as possible, and do so myself. And in fact now I'll add more details to what I provide. But recognizing that this isn't always possible, I am wondering what you, as a SAR person, think of the "electronic" approach. Wouldn't you be glad to be handed the last known GPS coordinates of the target of your search?

Thanks again for posting. It's definitely interesting to read from someone who actually does this stuff (SAR).
I know that I never understood SAR before... I'm still learning, tho it's two years I've been doing it. Still feeling like a noob sometimes.

The last known GPS coordinates? well, yes, if you also provide what geodetic datum you're using! If you're giving out coordinates using NAD27 CONUS and the SAR team getting the coordinates uses WGS 84, we could end up being quite a distance away from the actual location and never know it. We had some snowmobilers give us coordinates of a set of tracks they thought belonged to a lost snowshoer - we luckily thought to double check what their GPS was set to, and found they were using WGS 84 ("what's that mean??" they asked) and reset it to get accurate coordinates! Fresno SAR uses NAD27, which is what Tom Harrison and other commercially made maps (some older FS maps are WGS) use. You might want to check the GPS unit you use to be sure it's the same as your map, too, if you use both.

Actually, Yosemite has good cell service in Tuolumne Meadows campground. I know this because I was called out for a search at 2 am while staying there last year! Also you'll get service on many of the high points around Yosemite Valley (we had signal on Devil's Dance Floor, Half Dome, and Glacier Point) and in Curry Village. I had a couple bars over at the Lodge. You could always use WD's method of dropping a postcard in the mail, too. The post office isn't far from the Yosemite valley wilderness center, and at Tuolumne Meadows it's at the store. And there's a pay phone at the market in Yosemite Village, and there's a web kiosk at Degnan's Deli to dash off an overpriced email from a web account.

I know what you mean - I like to play trailhead bingo too! But when I go by myself these days I'm especially careful about leaving instructions, especially once I started SAR. They give out this humiliating award for SAR volunteers who need to be SAR'ed, you see....

(I didn't know what a geodetic datum was until I did some research prepping for training the newbies - it's astounding to me how complex maps can really be, how many different reference methods there are, and how much I never knew about these things... still not sure how it all works but at least now I know it's important to know what you're using, so you can inform others.)
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bheiser1
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Re: Let people know

Post by bheiser1 »

Hmmm, yes, that's another good point about the datum setting. The SPOT device sends a message like this:
------------------------
Latitude:37.2307
Longitude:-118.61832
GPS location Date/Time:07/03/2011 10:49:25 PDT

Message:I'm at the trailhead, starting on the trail now.
Click the link below to see where I am located.
http://" onclick="window.open(this.href);return false;<deleted for privacy reasons, this points to a personalized page>

If the above link does not work, try this link:
http://maps.google.com/maps?f=q&hl=en&g ... &z=12&om=1" onclick="window.open(this.href);return false;
-----------------------
As you can see the second link is a generic Google Maps reference. Most of the time it points to the exact spot.

If someone received this message, and subsequently felt the need to initiate a SAR, is it safe to assume they could email a message like this to the SAR team, or at least to someone in an office who could interpret it and advise the team by radio?

Anyway it sounds like you have better cell reception than I do with my AT&T iPhone :).

p.s. I just discovered the default datum for my GPS is WGS84, hmmm...
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Re: Let people know

Post by AlmostThere »

I have AT &T. :) Verizon works okay too. Sprint, well, good luck with that....

Good ol' lat and long... interesting that Google thinks North Lake is in Yosemite. We were talking about that the other day, all the ways googlemaps has at times led one or more of us to the wrong places. But with a coordinate like that we'd have the Inyo SAR walking around the whole parking area questioning people, looking for the vehicle and trying to get a good track.

At least your GPS is on something standard. A team mate's Garmin Rhyno came out of the box set to some obscure Estonian datum.The numbers it twas giving looked totally off.
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Re: Let people know

Post by wildrose »

I just did a 4 days backpacking in Yosemite. When I got my permit, the ranger didn't ask my car's plate number and didn't ask how many cars we had for our group. So I don't think they can link the hikers with the cars parked in the park.
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Re: Let people know

Post by AlmostThere »

wildrose wrote:I just did a 4 days backpacking in Yosemite. When I got my permit, the ranger didn't ask my car's plate number and didn't ask how many cars we had for our group. So I don't think they can link the hikers with the cars parked in the park.
Yes, they can. It takes law enforcement 5 minutes to run a plate and know who owns the car. They'll also see whether the person is reported missing, if the car was reported stolen, or if there are any other alerts placed on it.

We've done that - noticed a car in a lot that looked abandoned and run the plates.
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Re: Let people know

Post by yosehiker »

The difference between NAD 27 and NAD83/WGS84 is about 90 meters (~300 ft) in the Sierra's. NAD 83 and WGS 84 are almost identical, typically a meter or less difference between the two. Practically every map is based off of NAD 27 while practically every GPS receiver uses WGS 84 as that is what the GPS satellites use.

So as AlmostThere noted, check your datum and know the difference before you go out. I would also suggest using UTM instead of lat/long for navigation as it is much easier to use UTM to plot and find your location on a map. Many maps have UTM grid's on them in light blue lines and USGS quads have tick marks on sides and top showing 1 km UTM grids.

Whatever system you use, if needing to report your location, be clear in your datum, coordinate system and units. SAR can transform from one datum/coordinate system to another. But what they don't know they can't do. As for units, a lat/long of 37°43' 56.983" N 119° 33' 29.667" W can become 37.4356983 N 119.3329667 W if you don't clearly say if you are using decimal seconds or decimal degrees. Obviously, those two lat/long's are not that same.
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bheiser1
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Re: Let people know

Post by bheiser1 »

AlmostThere wrote: At least your GPS is on something standard. A team mate's Garmin Rhyno came out of the box set to some obscure Estonian datum.The numbers it twas giving looked totally off.
haha, as I was scrolling thru the settings I ran across one called, IIRC, "Early Egyptian". :)

It's amazing there are so many... it's a really long list...

Anyway, thanks again AlmostThere, and YoseHiker... good info!
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rlown
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Re: Let people know

Post by rlown »

AlmostThere wrote: The last known GPS coordinates? well, yes, if you also provide what geodetic datum you're using! If you're giving out coordinates using NAD27 CONUS and the SAR team getting the coordinates uses WGS 84, we could end up being quite a distance away from the actual location and never know it. We had some snowmobilers give us coordinates of a set of tracks they thought belonged to a lost snowshoer - we luckily thought to double check what their GPS was set to, and found they were using WGS 84 ("what's that mean??" they asked) and reset it to get accurate coordinates! Fresno SAR uses NAD27, which is what Tom Harrison and other commercially made maps (some older FS maps are WGS) use. You might want to check the GPS unit you use to be sure it's the same as your map, too, if you use both.

Actually, Yosemite has good cell service in Tuolumne Meadows campground. I know this because I was called out for a search at 2 am while staying there last year! Also you'll get service on many of the high points around Yosemite Valley (we had signal on Devil's Dance Floor, Half Dome, and Glacier Point) and in Curry Village. I had a couple bars over at the Lodge. You could always use WD's method of dropping a postcard in the mail, too. The post office isn't far from the Yosemite valley wilderness center, and at Tuolumne Meadows it's at the store. And there's a pay phone at the market in Yosemite Village, and there's a web kiosk at Degnan's Deli to dash off an overpriced email from a web account.

I know what you mean - I like to play trailhead bingo too! But when I go by myself these days I'm especially careful about leaving instructions, especially once I started SAR. They give out this humiliating award for SAR volunteers who need to be SAR'ed, you see....

(I didn't know what a geodetic datum was until I did some research prepping for training the newbies - it's astounding to me how complex maps can really be, how many different reference methods there are, and how much I never knew about these things... still not sure how it all works but at least now I know it's important to know what you're using, so you can inform others.)
Most use WGS 84 if they have a GPS. My Rhino came with that setting as the default. Why the NAD27 choice if most don't buy new maps? The conversion should be close if not spot on between the two, or 60+ given the choices. (well, about 10 for the continental US).. Garmin SW allows you to change between them all, so I would assume SAR knows how to do that as well.

only place my ATT cell picks up well is near the stables at TM..
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Re: Let people know (where you're going)

Post by rlown »

There's another aspect here that was lightly touched on.. Communications. My group regularly carries "walkie-talkies". According to some rangers on this forum, those public channels are not monitored. Why not in a rescue scenario? I understand the line-of-sight issue, but still, you'd think you'd monitor for that, esp if you think you're close to a lost hiker (assuming of course, they carry a comm device). Cell phones for the most part don't work off-trail or even on-trail.

Our group is always on 5.1.. That is synch'd and tested before we leave the trail-head.
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