On the go with GPS, map, compass and altimeter.
This article is about the common tools for orientation, their respective advantages and disadvantages, as well as numerous tips on how to get the most out of the different systems.
Orientation is basically about being able to visualise an image of the nature (topography, distances and additional information) in your head in order to find your way around the mountain. The more precisely this image is stored in the mind, the faster one can orientate oneself on site without further navigation aids. In terms of orientation requirements, we distinguish between route planning (What does the planned route look like?), location determination (Where am I? What do I see in the distance?) and navigation (How do I get to my destination?). For each of the tasks, I need to be able to orient myself in the best possible way. In addition, there is the time factor, which always plays a major role in the mountains. A good orientation and the routine handling of the different devices allows rapid progress, is an important safety factor and therefore of great importance. Here is an overview of the various systems and tools with their advantages and disadvantages:
The unbeatable advantage of the classic topographic paper map is its unfolded size, which makes it possible to link large-scale areas and small-scale details simultaneously. This allows you to get a very quick and comprehensive overview of the area, the “map in your head”.
This is technically not possible when viewing a small section of a map on a display – regardless of whether it is a smartphone or a GPS device – because details only become visible when zooming in, but at the same time the overview is lost. Thus, one must constantly zoom in and out, which is time-consuming and makes the cognitive overview of the given terrain more difficult with digital devices.
When determining a location, one must mentally reconcile the real terrain with the abstract two-dimensional representation of the map image. A solid handling of the map and the understanding of the printed information are the basic requirements for orientation: Knowing the different coordinate systems, reading contour lines/isohypses and equidistances correctly, interpreting terrain shapes and steepness, recognising signatures, drawings, shading – all of this has to be mastered. Especially during the planning stage, the help of a plan pointer for evaluating distances and direction angles is a valuable support. The more detailed you put all the information together in your head, the better you can orientate yourself – and that is precisely the actual goal.
The compass with bearing function (more accurate bussole) for determining the reference number/marching number is the indestructible workhorse for navigation and therefore indispensable. It requires no electricity and is reliable in use with gloves even in the most adverse conditions and in continuous use.
On the downside are the need to control declination, possible parallax errors and the susceptibility to magnetic interference.
In terms of handling, the altimeter has the same advantages in the terrain as a compass. As soon as the terrain becomes steeper, the altimeter complements/replaces the compass for orientation work. A compass is relevant in flat terrain, while an altimeter is more useful in a vertical wall. In hilly to mountainous terrain, the combination of both devices is a big help.
The disadvantages are inaccuracy with changing air pressure and the need for recalibration in the course of time.
Compass and altimeter complement the options for finding your way efficiently in open terrain: Bearing procedures (cutting forwards, cutting backwards, cutting sideways) with an altimeter and compass/bussole to prominent terrain points such as peaks, notches or glaciers enable orientation in unfamiliar terrain. Navigation via bearing/reference number is a great way to move forward in poor visibility.
The unbeatable advantage lies in the determination of the location when visibility is poor and the terrain is indefinable like on glaciers or uncut ice landscapes. The GPS (smartphone or stand-alone device) is thus virtually the gap-filler for optimal orientation.
The advantage of stand-alone GPS devices (Garmin etc.) lies in the fact that the reception of coordinates and displaying them are the only features of such devices and they do not consume power for anything else. This makes them very efficient in terms of consumption, even in cold temperatures. The devices are optimised for tough winter use and are easy to operate with gloves (this is where smartphones fail completely).
The disadvantages (compared to a topographic map and compass) are, apart from weight and additional space requirements, the fact that electronic devices are power-dependent and can therefore fail completely – depending on the terrain and situation, with fatal consequences.
Smartphone with GPS function
Today there is excellent software for smartphones (OruxMaps for Android) and a large selection of constantly updated offline maps worldwide (AndroidMaps and MapsForge). As a multifunctional device, you can communicate and navigate with your smartphone, which is very positive in terms of space requirements and total weight.
The disadvantages are the complexity of the settings (setup), sensitivity and handling (design). You cannot avoid taking off your gloves for precise operation. In extreme conditions such as strong wind (loss of gloves), moisture and cold (frostbite), this can have bad consequences. Another disadvantage is the increased power consumption if there is no control of the use of the different sensors and receiver modules. At best, you can recharge the smartphone with a powerbank, but this severely limits its use in complex terrain.
Regardless of whether it is a smartphone or a standalone device: The GPS for orientation is based on the classic orientation and thus offers a plus in safety: Determining the location in poor visibility or in uncropped terrain is an efficient way of orientation. Following programmed tracks or being able to return to the starting point using the track-back function are the outstanding features. However, tour planning is only possible with cutbacks, because a comprehensive overview of an area is very tedious and time-consuming due to the small display size.
Interesting field experiments
At the university in Kiel, test groups (divided into groups “only with city maps” and “only with navigation devices”) were sent out to foreign cities with a list of points to be approached. The city map groups reached their destination faster in all cases, which is due to a better orientation overview when using the maps.
The German military Navy is also increasingly training its sailors on the sextant again. After years of predominantly digital navigation, it was found that the soldiers were no longer as fit in navigation as they used to be. Two steps forward – one step back.