the basicsTime planning is an essential skill in the mountains, whether you're alpine climbing, ski mountaineering, backpacking or hunting. When headed into familiar territory, it's easy; but when you're headed somewhere new, the GuidePace app will help you base your time plan in reality.
GuidePace consists of three calculators for estimating travel time in different types of terrain. They are outlined in the sections below. You enter a rate, distance and elevation change, and it will estimate your travel time. The rate you specify is important, and it will depend on a variety of factors, including the characteristics of the terrain, party fitness and method of travel. Check out the 'about' section for each page to learn more about rates - you can access it by clicking on the book icon in the top right corner. As you gain experience using these systems, you'll begin to learn what to expect of yourself, and your time plans will become more accurate.
munter system ~ class 1, 2 terrain ~ hiking, skiing
Swiss guide Werner Munter developed the "Munter Method of Time Calculation" to estimate time for mountain travel in low angle terrain. It is particularly useful for developing tour plans and estimating approach times for alpine climbing, mountaineering and backcountry skiing objectives. The equation is as follows, with time in hours, distance in kilometers and elevation in meters:
time = (distance + elevation/100) / rate
Elevation change is considered as an absolute value. When traveling downhill a higher rate should be used, but greater elevation change will still result in greater travel time, as is the case in the field. Some typical, moderate rates:
uphill travel on foot or skis - 4
flat or downhill on foot - 6
downhill on skis - 10
bushwhacking - 2
chauvin system ~ class 3, 4 terrain ~ scrambling, snow climbing
American mountain guide Marc Chavin has developed the a system for estimated travel time in 3rd and 4th class terrain. It is also useful in other terrain with indistinct pitches, such as extended snow climbing.
His approach is to convert distance and elevation gain into an equivalent number of 60-meter pitches. Sixty meters is the current standard length for a climbing rope. Since most climbers are intimately familiar with this distance, they will find it easier to estimate the amount of time required for a single pitch than for the climb as a whole.
The equation is as follows, with time in hours, distance and elevation in meters, and rate in minutes per 60m pitch:
time = (distance + elevation) x rate
Typical rates in this type of terrain are 10-30 min/60m pitch.
|Photo: Silas Rossi, Guiding the West Ridge of Forbidden, North Cascades|
|Photo: Becky Burk, Sundance Mountain, RMNP|
technical system ~ class 5 terrain ~ rock, ice & mixed climbing
Roped climbing in technical terrain is typically broken up into pitches, which are up to one rope-length long. A typical pitch may take anywhere from 30 minutes to an hour or more depending on the difficulty of the terrain and skill of the party. The equation used by this calculator is simply:
time = pitches x rate
Technical decent times can also be estimated by substituting number of pitches for number of rappels.
|The Dangler, Shawangunks|
|Photo: Chris Sheridan, Cody, WY|
tour planning / putting it all together
Many times you'll encounter a variety of terrain on a single trip; this is where it is useful to make a tour plan. Break the trip up into legs, and then use GuidePace to estimate the time required for each leg!