Sahara West–East with VW Vans, 1984 • Part 6/8

See also:
Sahara West-East Crossings
Astro Navigation in the Sahara

Reports by Peter Reif
Photos by Peter Reif and Arike Mijnlieff

OSEWO Index Page

Part Six of Peter Reif’s report and maps recalling ÖSEWO: an Atlantic-to-Nile crossing of the Sahara in 1983-4. Despite their best efforts to acquire Libyan visas in Djanet, Algiers and Tunis, an escalation in the Libyan war with Chad means they can’t cross overland to Egypt and so have to ferry around across the Mediterranean.
For other parts, click the Index Page.

Next stage

Sahara West–East with VW Vans, 1984 • Part 5/8

See also:
Sahara West-East Crossings
Astro Navigation in the Sahara

Reports by Peter Reif
Photos by Peter Reif and Arike Mijnlieff

OSEWO Index Page

Part Five of Peter Reif’s report and maps recalling ÖSEWO: an Atlantic-to-Red Sea crossing of the Sahara in 1983-4. The team have arrived in Tamanrasset where they meet many other desert overlanders, as well as the Dakar Rally and three VW friends from Austria who’ve brought spare passports for Libya.
The four vans tick off the Hoggar Loop, then headed east for Djanet, close to the Libyan border.
For other parts, click the Index Page.

East to Djanet

Next stage

Sahara West–East with VW Vans, 1984 • Part 4/8

See also:
Sahara West-East Crossings
Astro Navigation in the Sahara

Reports by Peter Reif
Photos by Peter Reif and Arike Mijnlieff

OSEWO Index Page

Part Four of Peter Reif’s report and maps recalling ÖSEWO: an Atlantic-to-Red Sea crossing of the Sahara in 1983-4. Following the tough, three-week crossing of the Majabat al Koubra to Timbuktu, the two VWs head northeast back into the desert for the Algerian border they crossed two months earlier on the way down.
For other parts, click the Index Page.

Next stage

Sahara West–East with VW Vans, 1983 • Part 3/8

See also:
Sahara West-East Crossings
Astro Navigation in the Sahara

Reports by Peter Reif
Photos by Peter Reif and Arike Mijnlieff

OSEWO Index Page

Part Three of Peter Reif’s report and maps recalling ÖSEWO: an Atlantic-to-Red Sea crossing of the Sahara in 1983-4. The VWs load up and tackle the big 1500-km dune crossing of the Majabat al Koubra or Empty Quarter from Atar to Timbuktu.
For other parts, click the Index Page.

Next stage

Sahara West–East with VW Vans, 1983 • Part 2/8

See also:
Sahara West-East Crossings
Astro Navigation in the Sahara

Reports by Peter Reif
Photos by Peter Reif and Arike Mijnlieff

OSEWO Index Page

Part Two of Peter Reif’s report and maps recalling ÖSEWO: an Atlantic-to-red Sea crossing of the Sahara in 1983-4. The team get in position for the first big desert crossing.
For other parts, click the Index Page.

Next stage

Sahara West–East with VW Vans • Index Page 1/8

See also:
Sahara West-East Crossings
Astro Navigation in the Sahara

Reports by Peter Reif
Photos by Peter Reif and Arike Mijnlieff

OSEWO Index Page
Part 2
Page 3
Part 4
Part 5
Part 6
Part 7
Part 8/8

Austrian, Peter Reif spent his Lockdown formatting a series of detailed reports and maps recalling ÖSEWO: an Atlantic-to-Red sea crossing of the Sahara in 1983-4.
Volkswagen’s T2 Kombi was an unorthodox choice, especially as much of the route was off-piste, but as you’ll read over the next few posts, the vehicles managed better than you’d expect.

Next stage

Sahara Silhouettes 3

More Sahara silhouettes here and here.

J is for Jerrican

Part of the Sahara A to Z series

Filling up for the big one

For travellers who don’t expect to be making a lifetime of Sahara travel and haven’t got limitless funds, jerricans provide the simple answer to increasing your vehicle’s range. Available sometimes still unused from military surplus outlets for around £10, they make reliable and robust fuel containers. 

Captured WW2 kannister

The standard steel jerrican is a German design (hence the name) from the late 1930s, developed to support their blisteringly effective blitzkrieg invasions. The fact that the design remains unchanged today shows how well they succeeded with the ergonomics of carrying, pouring, sealing and storing fuel. During the war in North Africa, the LRDG prized the discovery of any jerricans, while the Germans were ordered to destroy them on retreat.

A jerrican holds 20 litres (4.45 gallons; 5.28 US gallons) when filled in the upright position. This leaves an air gap just below the handles which shouldn’t be filled with fuel (by tipping the can backwards) unless you’re really desperate. The air pocket, as well as the X-shaped indentations on the sides, enable the can’s sides to bulge as fuel expands; especially the case with petrol which is more volatile than diesel. Once warmed and shaken on your roof, take care to open the cap very slowly (the cap’s clamp design makes this easy) to avoid a spurt of fuel, which, besides being dangerous, is messy and wasteful. 

Algeria

A clamp-on spout (some with an integral gauze and breather tube) should make topping-up while holding a heavy can easier. But I find these clamp-on spouts often don’t seal well, fuel runs down your leg and their internal gauze slows down the flow rate, prolonging the effort in holding them up. A wide-bore funnel takes half the time. Rigid funnels get messy with diesel and are awkward to stow, so I prefer the ‘collapsible’ vinyl items with the end snipped off to make the hole bigger. Store them in a plastic bag or flat lunch box. Cutdown mineral water bottles will also do the job. 

Better still, leave the can where it’s stashed on the car and siphon the fuel into the tank either with a simple tube or a manual siphon-pump. Until mastered, the mouth-sucking method to get a siphon going is understandably unpopular with motor fuel. If you have no siphon pump bury the whole hose into a full jerrican (a flexible, clear, thin-walled hose is best). With the other end fully submerged, put your thumb over the end and draw out the tube which should stay full of fuel. Poke the tube into the fuel tank filler and the weight of the dropping fuel will create a siphon. 

Jerricans themselves can be knocked about for years: I’ve never seen a welded seam leak, though cap seals do leak. You can buy spare seals or, failing that, a chopped-up inner tube clamped across the mouth will work.

Once rust or flaking paint begin to come out of a jerry, either make sure you use a fine pre-filter or get another jerrican. Neat ten-litre versions are available and even mini five-litre models, all using the same clamping cap. They can also be robust containers for spare motor oils and other fluids and make good jack stands when working under a car.

There is said to be a small risk from static electricity in the dry desert atmosphere when refuelling vehicles, especially petrol. Earth the car by touching it before opening the cap and pouring in the fuel.

‘Jerricans’ copied in plastic should never be used for long-term fuel storage. The soft slab sides and screw-on caps are unsuited to the expansion and will swell like a balloon before splitting, leaking or bursting. I once drove a car carrying nearly three dozen cheap plastic jerries on the roof. Within a couple of days fuel was running down the sides of the car as the liquid expanded and caps leaked; I even had to use the wipers as it ran down the windscreen. It was very messy and bad for the rubber components.

Astro fix positioning in the Sahara

I recently received this interesting graphic from Austrian desert traveller, Peter R. In the winter of 1983-4 he and another T2 VW set off from Mauritania to cross the Sahara from west to east. Christmas Eve 1983 found them here, about 200km southwest of Aguelhok in northern Mali.
On that trip, which included a lot of driving off-piste, they used laborious astro-fixing to establish their position, when needed. The IGN maps of the era were (and still are) very good, and identifying distinctive isolated peaks or similar formations from maps helped with orientation.
Decades later Peter was able to pinpoint his festive position much more accurately combining high-resolution aerial Bing Maps imagery and the angles of the distinctive hills around them from photos taken on that day. Doing so revealed their astro fix position was about 600 metres off to the southeast, and their initial Dead Reckoning estimate was only about a kilometre to the SSE. Not bad at all.

I’ve never tried astro-nav nor met anyone who did it, even for a laugh. By the time I was exploring the desert away from pistes (where an accurate position is more useful), civilian GPS was available. Pre-GPS, I did occasionally use prominent landmarks for orientation by taking a bearing with a sighting compass, though my bike’s odometer (trip meter) was by far the most useful navigation aid, telling me how far I’d gone along a track; a form of dead reckoning which was easily estimated on a 1:1m scale IGN map where a 1mm equalled a kilometre on the ground.

Looking at Peter’s graphic makes me realise astro-fixing might also be a form of triangulation as one would use on land in a 2D plane. Except astro is in 3D and also requires accurate times combined with precise angles (declination) and bearings (azimuth) of easily found ‘landmark’ stars (above: Capella, Betelgeuse and Deneb) to triangulate a position on the ground. To measure these angles you need a tripod-mounted theodolite – as Peter’s group used for greater accuracy. You then need tables to convert you timing and other data into a terrestrial position. Around this time I remember certain calculators – you might even call them mini computers – became available which halved the time it took to secure a position to 45.
I suspect there’s probably a lot more to it than that. Here’s a lengthy report about experimenting with sextant (more suited to boats) positioning in the Sahara. The user averaged an error against GPS of 4km which makes Peter R’s reading all the more impressive (though it wasn’t done with GPS but photo orientation and triangulation)

Orion’s Belt or ‘North Pointer’ to me

I never knew so many stars were named. For example Orion’s Belt (which I’ve always seen as one side of an arrowhead pointing just west of north) is composed of Mintaka, Alnilam and Alnitak. And the two ‘pointer stars’ on the end of the Plough (aka: Ursa Major; Big Dipper) which lead to Polaris, are called Dubhe and Merak. (More here about how Polaris works). All these names sound Arabic. I remember Stanfords used to sell star maps, and on one camel tour, someone’s smartphone had an app to point at the night skies and identify constellations and maybe star names too. I dare say these apps are even cleverer now.

I also learned that estimating you N-S latitude (in the northern hemisphere at least) is as easy a taking an angle off Polaris – the North Star around which all stars rotate. You can do this roughly with a baseplate compass. I remember an old Silva Ranger compass had a clinometer which makes this a bit easier. Now I think about it, Polaris is usually quite low in the Sahara sky; about 25° above the horizon which sounds about right. A good trick is measuring with your extended fist which equals about 10 degrees. So in the Sahara Polaris is 2.5 extended fists above the horizon.
That’s been done by navigators for millennia, but some may remember Dava Sobel’s popular 1995 book Longitude which described the Longitude Act of 1714 to egg on the invention of very accurate clocks or chronometers to help mariners calculate E-W longitude, the missing link and handy for crossing the Atlantic.
Like so much else, I’ve forgotten most of the Sobel book, but the video below explains the principl very clearly around 5:25. With a chronometer set at Solar noon at Greenwich, clocking midday anywhere else and working out the time discrepancy at 15° to the hour, gives a number of degrees of longitude (and so a distance) off the Prime Greenwich Meridian, north or south of the equator.

I looked on YT for a video which might summarise astro-fixing succinctly, but many were aimed at mariners and stretched on for hours. This snappy video, complete with a jaunty soundtrack, gives you the basics on orientating yourself (finding north). That’ll do me for now.

S is for more Sahara Silhouettes

Other silhouette galleries

Part of the occasional Sahara A to Z series