Mountain Locator Unit
Encyclopedia
A Mountain Locator Unit or MLU is a radio transmitter designed to be used by mountain climbers
as an emergency locator beacon when the wearer needs rescue.
Unique to Mount Hood
, these devices can be rented for $5 at Portland
-area outdoor shops and the Mount Hood Inn at Government Camp
, which is open 24 hours a day. The MLUs are simple radio beacons, and thus require search and rescue
rs to use traditional radio direction finding (RDF) equipment that provides a bearing
, but not a precise location, to the beacon.
Groups scaling the mountain are recommended to carry an MLU 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.
According to Steve Rollins of Portland Mountain Rescue
, the units are worn on a sash across the chest and are relatively light. This is less expensive than either purchasing or renting a personal locator beacon, which typically cost significantly more than $500 or rent for $50 per week, but include a GPS receiver and a transmitter designed for reception by a satellite network, for increased coverage and decreased response time.
The Mount Hood MLU system is controlled and maintained by the U.S. Forest Service and Clackamas County Sheriff. Transmitters broadcast at 168.54 MHz and provide good signals when buried in snow. It can be received at up to 20 miles (32.2 km), though the signal travels in line of sight, so it can't be received from behind a ridge or deep in a canyon. The technology is very similar to wildlife tracking systems.
A Mountain Locator Unit only transmits a signal. It cannot be used by the lost to gain any information, not even to find others with such a unit. Signal reception is by searchers cooperating with the Clackamas County Sheriff, and they listen for signals only when a rescue search is activated. A search is activated when a registered climber is overdue, or when specifically requested.
Oregon State Representative John Lim
(R) introduced House Bill 2509, which would require climbers to use an electronic signaling device when climbing above 10,000 feet between November and March. The Oregon House of Representatives
passed an amended version of the bill 33 to 22 on March 28, 2007 after a lengthy floor debate and passed it onto the Oregon State Senate
where it died in committee. The bill was widely opposed by mountain rescue organizations for its unintended consequences which would increase climbing accidents.
Mountaineering
Mountaineering or mountain climbing is the sport, hobby or profession of hiking, skiing, and climbing mountains. While mountaineering began as attempts to reach the highest point of unclimbed mountains it has branched into specialisations that address different aspects of the mountain and consists...
as an emergency locator beacon when the wearer needs rescue.
Unique to Mount Hood
Mount Hood
Mount Hood, called Wy'east by the Multnomah tribe, is a stratovolcano in the Cascade Volcanic Arc of northern Oregon. It was formed by a subduction zone and rests in the Pacific Northwest region of the United States...
, these devices can be rented for $5 at Portland
Portland, Oregon
Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...
-area outdoor shops and the Mount Hood Inn at Government Camp
Government Camp, Oregon
Government Camp is an unincorporated community located in Clackamas County, Oregon, United States, south of Mount Hood and north of Tom, Dick and Harry Mountain. It is a gateway to several ski resorts, the most popular being Timberline Lodge and Mount Hood Skibowl. Also, Government Camp has its...
, which is open 24 hours a day. The MLUs are simple radio beacons, and thus require search and rescue
Search and rescue
Search and rescue is the search for and provision of aid to people who are in distress or imminent danger.The general field of search and rescue includes many specialty sub-fields, mostly based upon terrain considerations...
rs to use traditional radio direction finding (RDF) equipment that provides a bearing
Bearing (navigation)
In marine navigation, a bearing is the direction one object is from another object, usually, the direction of an object from one's own vessel. In aircraft navigation, a bearing is the actual compass direction of the forward course of the aircraft...
, but not a precise location, to the beacon.
Groups scaling the mountain are recommended to carry an MLU 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
Mount Hood climbing accidents
Mount Hood climbing accidents are mountain climbing- or hiking-related incidents on Oregon's Mount Hood. As of 2007, about 10,000 people attempt to climb Mount Hood each year. As of May 2002, more than 130 people have died climbing Mount Hood since records have been kept...
.) 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.
According to Steve Rollins of Portland Mountain Rescue
Portland Mountain Rescue
Portland Mountain Rescue is a search and rescue organization based in Portland, Oregon, United States. It specializes in high angle mountain rescue in northwest Oregon and southwest Washington, as well as providing educational materials and information for the local mountaineering community...
, the units are worn on a sash across the chest and are relatively light. This is less expensive than either purchasing or renting a personal locator beacon, which typically cost significantly more than $500 or rent for $50 per week, but include a GPS receiver and a transmitter designed for reception by a satellite network, for increased coverage and decreased response time.
The Mount Hood MLU system is controlled and maintained by the U.S. Forest Service and Clackamas County Sheriff. Transmitters broadcast at 168.54 MHz and provide good signals when buried in snow. It can be received at up to 20 miles (32.2 km), though the signal travels in line of sight, so it can't be received from behind a ridge or deep in a canyon. The technology is very similar to wildlife tracking systems.
A Mountain Locator Unit only transmits a signal. It cannot be used by the lost to gain any information, not even to find others with such a unit. Signal reception is by searchers cooperating with the Clackamas County Sheriff, and they listen for signals only when a rescue search is activated. A search is activated when a registered climber is overdue, or when specifically requested.
Oregon State Representative John Lim
John Lim
John Lim is a Republican politician in the United States state of Oregon. He has served in both houses of the Oregon Legislative Assembly and was the Oregon State Senate Majority Leader in 1995. He has unsuccessfully ran for the U.S. Senate and for the Republican nomination for Governor of...
(R) introduced House Bill 2509, which would require climbers to use an electronic signaling device when climbing above 10,000 feet between November and March. The Oregon House of Representatives
Oregon House of Representatives
The Oregon House of Representatives is the lower house of the Oregon Legislative Assembly. There are 60 members of the House, representing 60 districts across the state, each with a population of 57,000. The House meets at the Oregon State Capitol in Salem....
passed an amended version of the bill 33 to 22 on March 28, 2007 after a lengthy floor debate and passed it onto the Oregon State Senate
Oregon State Senate
The Oregon State Senate is the upper house of the state-wide legislature for the U.S. state of Oregon. Along with the lower chamber Oregon House of Representatives it makes up the Oregon Legislative Assembly. There are 30 members of the State Senate, representing 30 districts across the state,...
where it died in committee. The bill was widely opposed by mountain rescue organizations for its unintended consequences which would increase climbing accidents.