Fuel: Metal jerry cans are the best choice because they’re extremely safe as well as being easy to handle.
How much should you carry? It’s as vital to carry sufficient fuel and reserves in the desert as it is not to overload the vehicle. Fuelling points are invariably widely spaced; the distance between them is a major criterion in selection of vehicle, total payload left over for the crew and other supplies. If ‘D’ is the distance between fuelling points: total gallons required = (D + 25 per cent + 150 kilometres) divided by expected kilometres per gallon (ie a reserve of 25 per cent plus 150 miles to cover diversions and difficult going).
Distance: Away from tracks (eg an expedition reaches a base supply town and then branches out across the country), D will be a distance measured off a map. Factor it according to terrain; on a big map (1: 1 m, say) actual distance will be about 1.2 times measured distance, given reasonable going such as gravel and some stony regions. Savannah, slow going with much zigzagging between grass tussocks, will be 1.3; sand dunes 1.5 to 2; and smooth sand/gravel plain 1.1.
Fuel accounting: It’s essential to do a nightly calculation of your fuel consumption and check fuel remaining in tanks and cans. Know exactly the amount used to top up each night and divide it into the distance covered.
Water: Hard polythene military-like jerry cans are unsurpassed for normal use. For one or two days, a cooler filled with ice can be topped up as required.
Experience over a number of expeditions shows water requirement at low physical workloads is 7.5 to 10 litres per head per day with night/day mm/max 5—35°C; 12.5 to 20 litres per head per day with night/day mm/max 25—45°C.
For how many days does this hold true? There are no hard and fast rules, but a minimum of three extra days’ worth is a prudent reserve to cover, say, timeconsuming breakdown repair work. Thus a journey involving six days of travel would need a nine-day supply of water.