Mountain Locator Unit

A Mountain Locator Unit or MLU was a radio transmitter for use by mountain climbers as an emergency locator beacon when the wearer needs rescue.

The MLUs were simple radio beacons, and thus required search and rescuers to use traditional radio direction finding (RDF or DF) equipment to obtain a bearing, but not a precise location, to the beacon.

Unique to Mount Hood,{{cite web

| url = http://www.oregonlive.com/weblogs/print.ssf?/mtlogs/olive_oregonian_news/archives/print214894.html

| title = Mountain Locator Unit could have helped two climbers

| publisher = The Oregonian

| access-date = 2007-04-01

}} these devices could be rented for $5 at Portland-area outdoor shops{{cite web

| title = Portland Mountain Rescue: Search for Missing Mt Hood Snowshoer Ends

| url = http://www.pmru.org/pressroom/headlines/hoodsnowshoe030303.html

| access-date = 2007-02-19

| archive-url = https://web.archive.org/web/20060925153828/http://www.pmru.org/pressroom/headlines/hoodsnowshoe030303.html

| archive-date = 2006-09-25

| url-status = dead

}} and the Inn, open 24 hours a day. The units were available from the late 1980s until 2017, but advances in technology now provide superior locating information by devices such as a PLB, InReach or Spot.

Groups scaling Mount Hood are recommended to carry an emergency signaling device and all climbers must register before climbing and sign out upon return.

The MLU was designed after a school group with two adults and seven children perished on Mount Hood in 1986. (See Mount Hood climbing accidents.) The bodies of some of the group were found in a snow cave a day after the searchers had passed within fifteen feet of their shelter without noticing them.{{cite web

| title = Mount Hood - The Episcopal School Tragedy

| url=http://www.traditionalmountaineering.org/Report_Hood_EpiscopalSchool.htm

| access-date = 2007-02-19

}}

According to Steve Rollins of Portland Mountain Rescue, the units could be worn on a sash across the chest and were relatively light. Renting MLU's was less expensive than either purchasing or renting a personal locator beacon, which typically cost several hundred dollars to buy, or rent from various sources for around $50 per week.{{cite web

| url = http://www.plbrentals.com/

| title = PLB rental information

| publisher = PLB Rentals, LLC

| access-date = 2007-02-20

}}

The Mount Hood MLU system was controlled and maintained by the U.S. Forest Service and Clackamas County Sheriff. Transmitters broadcast at 168.54 MHz and provided good signals even when buried in snow. They could be received at up to {{convert|20|mi|km}}, though the signal travels in line of sight, so they could not be received from behind a ridge or deep in a canyon.{{cite web

| url = http://www.traditionalmountaineering.org/News_Lost_HoodGroup.htm#climbers

| title = Mountain Locator Units on Mount Hood

| author = iain

| date = 2006-12-16

| access-date = 2008-07-04

}} The technology is very similar to wildlife tracking systems.{{cite web

| url = http://www.npwrc.usgs.gov/resource/wildlife/radiotrk/radiotrk.pdf

| title = A Critique of Wildlife Radio Tracking and its Use in National Parks—A Report to the U.S. National Park Service

| author = L. David Mech

|author2=Shannon M. Barber

| pages = 12

| date = 2002-02-06

| access-date = 2008-07-04

}}

A Mountain Locator Unit only transmitted a signal and did not initiate a rescue (when you activated an MLU beacon, there was no one monitoring for signals, the device only assisted rescuers in locating lost climbers once a rescue has been requested by other means and rescuers know to listen and search for the beacon's signal. They were also not designed to be used for avalanche safety (avalanche beacons are entirely different than what MLU's were designed for.)

The use of MLU Beacon technology was overtaken by availability of Personal Locator Beacons (PLBs) and other technologies such as "SPOT Satellite GPS Messengers". These newer technologies not only allow rescuers to determine your location, but they also have the ability to initiate a rescue by alerting authorities that you are in need of help.

In fact, most modern cell phones have built in GPS receivers. If a climber calls 911, the cell phone may automatically provide emergency services with the climber's GPS coordinates. Cell phones also allow the lost or injured climber to provide important information to rescuers, such as the nature of any injuries; however, cell phone coverage on Mount Hood can be spotty and they are therefore not necessarily a replacement for other technologies such as PLBs which leverage satellites overhead for communication.

Oregon State Representative John Lim (R) introduced [https://web.archive.org/web/20070211052745/http://www.leg.state.or.us/07reg/measures/hb2500.dir/hb2509.intro.html House Bill 2509], which would require climbers to use an electronic signaling device when climbing above 10,000 feet between November and March.{{cite news

| url = http://www.cnn.com/2007/US/02/19/climber.safety.ap/index.html

| title = Oregon bill would require climbers to carry beacons

| date = February 19, 2007

| publisher = CNN / Associated Press

| access-date = 2007-02-20

|archive-url = https://web.archive.org/web/20070221025116/http://www.cnn.com/2007/US/02/19/climber.safety.ap/index.html |archive-date = 2007-02-21}} The Oregon House of Representatives passed an amended version[http://www.leg.state.or.us/07reg/measures/hb2500.dir/hb2509.a.html A-Engrossed House Bill 2509] {{webarchive|url=https://web.archive.org/web/20070810103155/http://www.leg.state.or.us/07reg/measures/hb2500.dir/hb2509.a.html |date=2007-08-10 }} of the bill 33 to 22 on March 28, 2007 after a lengthy floor debate{{cite news

|last=Har

|first=Janie

|url=http://www.oregonlive.com/news/oregonian/index.ssf?/base/news/1175135139152270.xml&coll=7

|title=House OKs mandate for Hood locators

|work=The Oregonian

|date=March 29, 2007

|access-date=2007-03-30

}} and passed it onto the Oregon State Senate where it died in committee.[http://www.leg.state.or.us/07reg/pubs/hsemh.html 2007 Oregon House Measure History] {{webarchive|url=https://web.archive.org/web/20070320080225/http://www.leg.state.or.us/07reg/pubs/hsemh.html |date=2007-03-20 }} The bill was widely opposed by mountain rescue organizations for fear that it would cause inexperienced climbers to rely on rescuers to save them rather than learning to become self-reliant.{{cite web

| url = http://www.traditionalmountaineering.org/News_HB2509.htm

| title = Oregon HB2509 mandates electronic signaling devices on Mount Hood—Climbers' Views

| date = 2007-10-19

| access-date = 2008-07-03

}}