How Not to Get Stuck in the Sand Dunes

As you saw in the video highlights from last year’s Dakar (three posts ago), even the pros find it hard not to get stuck in the sand dunes.  No matter how fast you are on hard surfaces, the sand will get you.  And this year we have extra sand, most of the Dakar will take place in Mauritania, which is mostly dunes.  This beauty was taken in Marzuga, Morocco:

The Desert Warrior is optimized to drive on sand: it is very light to begin with, and by operating on diesel it carries less fuel (about 200 kg); when you get to the dunes you need to deflate the tiers, to about 1 bar, so the tier flattens out and has better grip.   The Desert Warrior has separate front and rear differential locks, pneumatically activated by the driver. But then you still need to be able to read the terrain, to know from which direction the wind blows , and how to cross the dunes.

Egg Cartons in the Dessert

Think of sand dunes as a (soft) egg carton: a series of bowls, each bowl is surrounded by ridges.  The bottom of the bowl is flat and firmer to drive on, the ridges are steep and soft.                                              You got to drive over a ridge to get to the next dune.  Most times you cannot drive on the ridge line itself (too narrow, you will roll over), and you cannot just drive straight up to the ridge: you will lose too much momentum (too steep, too soft) and get stuck in no time. 

What to do, then? When we trained in Morocco Paul and Beady showed us a technique they use to drive over dunes.   It is very effective, and, believe him or not, Martin claims that in their 2007 Dakar he and Paul didn’t have to shovel themselves out of the sand even once.

Dune Surfing

What you do is try to “surf” the dune.  When you’re at the bottom of the bowl, drive around in circles and gather as much speed as you can; with more speed you build momentum that allows you to get higher on the dune’s ridge, about 2/3 of the way up; but you drive parallel to the ridge, not perpendicular.  Once you have enough momentum and you’re high enough, lift your head and look for a crossing spot, typically a lower saddle between two peaks (remember the egg carton?).  Keep your momentum to get to the ridge line, and as you crest the ridge, immediately lift your foot from the accelerator, brake gently, and pick your route into, and out of, the next bowl.  As you descend into the next bowl you build up momentum, and so forth for the next 200 miles 🙂

Check out this slide-show to get a sense of what I’m talking about:

This “surfing” technique is very effective and fun, once you get it.  It doesn’t always work, though, as the sand may be too soft, the dune too steep, or you just don’t have enough speed; remember that you can always trade-off height for speed (for those of you who are pilots, I’m sure you get exactly what I’m talking about).   so, if you find yourself on the ridge, your momentum just died, and you feel you will get stuck in the sand any second now, just turn your steering wheel towards the bottom of the bowl, and accelerate (that’s right) downwards; with enough speed and a bit of luck, by the time you get to the bottom you have enough momentum to start the maneuver all over again (and if it didn’t work, well, start digging!).

See how Nadav gets out of a messy situation after he got the the top of the ridge but lost all his momentum (there may be a bug here; if this window doesn’t show a slideshow, just click on the “x” mark on the top right corner):

BTW, both slides shows where created by Slide.com.  I’d be interested in your comments, which style did you like best, the “Slide Show” or the “8 mm”?  Let me know by leaving a comment on this post.