The link is not working.Originally Posted by upstream
Hopefully someone who has knowledge in cell phone capabilities can weigh in on this.OK, thanks. I couldn’t recall whether she had a map or not. There was all that talk about what exactly was shown on the maps and I didn’t want to go reread all the threads and posts. I remembered there was a text and a cell ping…so by scarce I meant just one. I only know a little about cell phones and transmissions but I do have decent familiarity with geography, see if this makes sense. While her phone pinged the tower once, the phone may have picked up the tower more than once. Whether this is stored I don’t know. This could happen if the tower signal is strong enough to reach the phone but the phone is not strong enough to reach the tower. So if she is moving and the phone can only see but not ping the tower, there will be multiple points from which to draw the circles around the tower in order to triangulate her position. Additionally, any GPS data from the phone would help to triangulate her position and in all likelihood would be time stamped. If she took any photos, those might be georeferenced, and definitely time stamped. If she tried to call 911, the phone will automatically calculate the GPS location as that is transmitted to the operator. I would imagine the phone would store that. Whatever is culled could be dumped into a GIS, and estimates for speed of travel added (both on and off trail) and the forensics folks might be able to provide some reasonable zones where she might have been. Which they might have already done or just have some preliminary results that lack 100% certainty, thus their saying she was lost but don't know where she left the trail.
Just having the profile map in the guide leaves the hiker with a huge dearth of topographic information when lost. Be safe and carry a map. Please do.
I recall having a discussion one night in a shelter in PA with a engineer whose job was to plan the locations of cell towers. I asked why I can see the signal strength drift in and out from zero or one bar, then to two or three and then back to one. Why is it that sometimes I can get a text out and a few minutes later, from the exact same spot not be able to get out at all? He told me that in the mountains you're often not getting a "clean" signal, instead you're getting a signal that has bounced around between the mountains (reflected) before getting to you. A good signal, one you could actually talk on (since talking takes a whole lot more capacity then text) is a "line of sight or clean" signal.
I don't know how this relates to Gerry other than a weak cell signal might not be all that reliable when used to locate someone.
"Chainsaw" GA-ME 2011
911 operators aren't going to get GPS in the vast majority of cases, and certainly not in a rural area. Phase II 911, which is probably the best you're going to have in a rural area, triangulates a cell phone's position by hitting off of the towers in the area and guessing where you are based on how your signal bounces off those towers...if there are only one or two towers you are connecting to its going to be nothing more than a WAG. Best case scenario they can pinpoint you to within a few meters but more likely 50 to 100 meters or even worse. A cell phone signal can fluctuate between 0 and 4 bars like you describe because of weather. Where I live I'm on the wrong side of a hill so I get very spotty cell service. I get a better signal on days when there is cloud cover...reason being the signal bounces off the clouds and can make it to the other side of the hill. As those clouds move around and the signal bounces you see that fluctuation. Most of the time my phone connects about every 10 to 20 minutes, so it is easier to get in touch with me by text or voicemail and then I can get to an area where I have a better signal to call them back.
911 operators aren't going to get GPS in the vast majority of cases, and certainly not in a rural area. Phase II 911, which is probably the best you're going to have in a rural area, triangulates a cell phone's position by hitting off of the towers in the area and guessing where you are based on how your signal bounces off those towers...if there are only one or two towers you are connecting to its going to be nothing more than a WAG. Best case scenario they can pinpoint you to within a few meters but more likely 50 to 100 meters or even worse. A cell phone signal can fluctuate between 0 and 4 bars like you describe because of weather. Where I live I'm on the wrong side of a hill so I get very spotty cell service. I get a better signal on days when there is cloud cover...reason being the signal bounces off the clouds and can make it to the other side of the hill. As those clouds move around and the signal bounces you see that fluctuation. Most of the time my phone connects about every 10 to 20 minutes, so it is easier to get in touch with me by text or voicemail and then I can get to an area where I have a better signal to call them back.
try this http://www.caltopo.com/m/H3NN
Thanks very much
+++1, It just baffles me why someone going into an unfamiliar area would not carrying one. Just leaves too much to chance. A 3 foot wide treadway isn't the only thing out there. A guide is helpful but falls far short of a decent topo map. Even maps which show just the trail corridor can be less that helpful if you get beyond the borders of the map.
The map in post #2005 shows an AT route which I don't believe is the current route which is much farther east. Can someone explain this?
I'm having a hard time seeing where the AT is on this map. When I zoom out a bit a thin white line appears to enter from the Saddlebacks and exit towards Spaulding. But the areas searched is covering the trail corridor I think? At any rate this shows her much closer to the trail than I thought.
AT02, LT 03-04, BMT05, NPT06, Haute Route07, Abol Ridgerunner 07/08, EBC Nepal trek 10
I've added the ATC data for the trail. If you change the base layer, you can see older versions of the trail.
The ATC data is dated 2012, so if there has been any reroutes since then, I don't know.
You can also change the shading level of the layers, to see the base layer better.
http://caltopo.com/m/H3NN
Maybe I missed it in earlier posts, what is P1...Ping? and what is Texsaid?
Ya sorry Alligator. I didn't mean to say that you're 'brash.' You seemed to by trying to think like Inchworm would and she was very conservative, the opposite of brash. I just didn't type it right. I like your contributions many thanks. My knowledge of cell phone triangulating is very weak. The authorities could not triangulate her with cell phone towers, as Don says, but maybe the rules change when the actual cell device is scrutinized. I haven't the foggiest. I wouldn't be shocked if she did have a gps app, which usually work without cell service, in addition to other info recovered from the device. I do believe we will learn of that eventually.
Interesting but the linked map seem to show an unmarked trail which connects with the current AT and water 50 meters from where the body was found
P1 is just a reference point I used to help align the image. texsaid is at the coordinates TexasBob said.
I was estimating from looking at a lot of stuff that has been in the news but you did a better job than I did, thanks for doing this. One thing that I noticed on the Caltopo maps is there are a bunch of intersecting trails right in the area where Inchworm was found that don't show up on Google maps.
I'm not sure if they are trails or the GPS tracks that the search team took.
Here is the map with the search info removed except where inchworm was found and you can see what look to be trails in the area.
https://caltopo.com/m/6K1A
Thanks. I see that she is also next to a small stream.
Well, fellow White Blazers, this thread has been quite interesting and informative. Now that InchWorm has been found and the final medical report issued I think it's time to put a end to this tragic accident. Never mind continuing on with the speculation, as to why it happened, let's all stop and let Geraldine RIP. I know she is now enjoying many "happy trails."
Last edited by Farr Away; 11-09-2015 at 14:43.
Grampie-N->2001
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