[This is the second entry on this subject]
So a friend and I were discussing devices to locate someone. I was pointing out the limitations of Avalanche Transceivers, and she was suggesting the SPOT personal locator beacon (PLB) that uses GPS technology (http://findmespot.com others listed at:http://www.rei.com/category/40002203). to be fair it's a lot more than just a PLB and you pay for that fact as it's a great, but very pricey service.
Avalanche Transceivers have a range of less than a football field. PLBs have a world wide range, but don't work under cover - meaning inside buildings, caves, thick woods, and most relevantly under a huge pile of snow that's just dropped on you. It occurred to me this morning (but before doing the research below) that the well dressed mountaineer would have to carry both(!). The GPS to get your rescuers to the avalanche area and the transceiver to help recover the body. This is not a joke. If you get buried in snow you usually have 30 minutes max. There are devices to help you get more air such as the Avalung (and here is an account of a very brave person testing it: http://outside.away.com/outside/features/200506/buried-alive.html) but that doesn't stop your core body temperature from dropping or CO2 poisoning from starting to set in.
HOWEVER! Mt Hood has designed a device to address all of these issues. It has the innocuous name of Mountain Locator Unit and more info on it is here: http://en.wikipedia.org/wiki/Mountain_Locator_Unit.
MLUs are radio wave based, and have a line of sight range of 20 miles which covers Mt. Hood quite nicely and it goes through snow AND they can be rented for $5 from the outdoor shops or from the Mt Hood Inn at Government Camp which is open 24 hours a day. It transmits at 168.54 MHz and rescuers have to use their own sensors to find them. You could point out that the weather was so bad that this would not have saved the currently missing climbers, but the device was invented after the horrible May 1986 incident when seven students and two faculty of the Oregon Episcopal School froze to death during an annual school climb (http://en.wikipedia.org/wiki/Mount_Hood_climbing_accidents) where rescuers walked right by their snow cave. For whatever reason (I am not speculating publicly on this one), Mt Hood likes to kill Christians as this is the 3rd well documented time.
So this availability is why the local Oregon public is particularly angry and I must say they do have a point. An MLU is not likely to save your life, but it would give your loved ones some peace. (If you are interested in saving your own butt your party will still need to carry your own Avalanche Transceivers unless they start making the MLU Receivers available to other people besides rescuers.) Unlike Mt Foraker where Sue Nott and Karen McNeil were lost, Mt. Hood is a popular, well trodden mountain, if the batteries lasted long enough, someone would find you ... eventually.
The mountaineering community opposes mandatory use of MLUs as it would increase the chances that someone might take. I'm not sure that's entirely valid though there are examples of people with Personal Locator Beacons doing dumb things (don't have a ready reference sorry). But you don't usually see people testing out their car's airbags just for fun, so I think it's certainly time to try a MLU mandate on Mt Hood, as the voluntary way just isn't working as well as we want it to. More info here: http://blog.oregonlive.com/breakingnews/2008/01/the_technology_mountain_locato.html
Here is a video that describes how the MLU was used to rescue a climber in Oct 2007. It does a great job of showing just how ridiculous conditions can get on that mountain: http://www.youtube.com/watch?v=OJSN2IgKiJg and it also illustrates how zeroing in on it requires two teams of rescuers using triangulation (look it up) and some expertise. I'm hoping that new technology will help redesign it to include GPS as that would save time, and maybe something that members of the climbing party can also carry instead of having to rely on rescuers.
Maybe the well dressed climber needs to carry all three? Talk about a burden. Ok, maybe not. If I had to choose one, on Mt Hood it's obviously the MLU. When not on Mt Hood who knows probably a PLB and if they wanted to find my body in the football field of snow they narrowed it down to, they can then bring a dog and metal detectors.
So what am I going to do? Stick to popular areas during good weather. I am a fair weather climber and I still manage to have some pretty cool adventures. My first time on Mt. Hood I'll use a guide (it may be a short mountain - lower that the elevation of Mt Whitney's Trail Camp, but it is obviously treacherous.). I've been on Mt. Shasta, so many times that I'm knowledgeable about the lower elevations on the South routes (to the point I could guide them and do for friends) and I wouldn't go higher without a GPS and map/compass anyway.
Anyway it's going to be interesting to see what the future brings us in Locator Devices.