Desert Odyssey: A road-trip feature

It remains a challenging trip that requires careful planning, a properly prepared four-wheel-drive vehicle and the right gear if it is to be done enjoyably and safely.

These days you'll meet other desert nomads on a journey through the Simpson, but it is still a wild, lonely place.

Each evening you can set up camp between the dunes, lie back in the swag and float among the stars. It's an eerie sensation the sky above seems like a black glass dome, lit by thousands of pinpoints of light. Within it, all is silent.

During the day the driving is slow and time again seems suspended. You crest a dune – there are 1100 of them – and see wave after burnt red wave stretching into the distance. Occasionally a salt lake gleams white between the dunes; the sky is the deepest, brightest blue.

At sunset the light softens, taking on an intense, saturated quality. The dunes glow, the sky slowly darkens overhead, holding on to the last flickers of orange as the sun sets. The dome descends once more. Your other life seems far, far away and a long time ago.

Our Simpson expedition numbered five kids aged six to 15, three adults, Toyota LandCruiser and Nissan Patrol turbo diesel automatics and everything including the kitchen sink.

We took the QAA and French Line tracks, at 450km the shortest and, according to the pundits, roughest tracks across.

The Rig Road is the other main track. It is longer, more than 700km if you cover its full length, but reputedly easier and more scenic. The other east-west route is the WAA line, which runs between the French Line and the Rig Road.

Several north-south tracks – K1 Line, Colson, Erebena and Knolls – run between the dunes, forming a grid with the east-west routes.

Birdsville is your last chance to pick up information on conditions in the Simpson and supplies for the trip. After Birdsville, there's absolutely nothing until you reach the Dalhousie Springs camping ground on the other side of the desert; the next fuel pump is another 70km further on at Mt Dare on the way to Alice Springs, or south at Oodnadatta.

Conditions can change on a daily basis in the Simpson, so what you read beforehand in the guidebooks is not necessarily what you'll find when you get there.

The proprietor of the Birdsville caravan park knew what she was talking about, so we took her advice. The Rig Road, she said, was a mess and very difficult. The French Line was fine, but Eyre Creek, 65km west of Birdsville, was full after recent rain so a 60km detour was necessary.

The first sand dune you hit after leaving Birdsville is Big Red. At 40m, it defeats many four-wheel drives but, as with most of the Simpson's difficult sand dunes, there is a short, easy detour around the base.

Everyone has a crack at Big Red. The LandCruiser and Patrol, with the torque-iest turbo diesels in the business, walked over it with ridiculous ease.

After Big Red you're in the desert proper. The initial 170km on the QAA Line to the Northern Territory border sees the dunes spaced widely apart, with a flattish 200-800m between.

Eyre Creek was, indeed, full. This didn't stop a group trying to cross from the other side. They got stuck, of course, and while trying to recover one of their utes from the creek a shackle broke and severely injured a woman travelling with them.

It was a graphic example of how the Simpson, and the outback in general, is unforgiving of carelessness and mistakes. No ambulance was going to show up in 10 minutes. We were carrying a satellite phone, so were able to call Birdsville and arrange for medical help, which came out to meet the group in the desert.

The other vital piece of safety gear on a Simpson trip is a two-way radio for short-range communication. Using Channel 10, we were able to monitor vehicles coming west-east, so we wouldn't have an unfortunate meeting at the top of a sand dune.

Simpson lore also requires at least the lead vehicle to have a tall aerial with a flag or two flying at the top. This allows oncoming traffic to see you before you get to the crest of a dune, avoiding a collision. Many a Simpson trip has come to a crashing conclusion in this way.

Travelling with five kids in such remote country also requires a lack of urgency. Setting and packing up a camp – we had a tent for each child – takes a couple of hours at each end of the day, and we found ourselves with about five hours' daily driving time.

If you have the luxury of several weeks instead of our two, take it. We didn't push the kids too hard – though they came close to the whinge threshold a few times, at which point we stopped and let them run around in the great nowhere – and they enjoyed the trip immensely, but it would have been nice to have the luxury of a drive-free day to do some exploring on foot and let the kids find their own desert surprises.

When you reach the Northern Territory border, the track swings south for 18km, running between a couple of salt lakes, to Poeppel Corner where the Territory, South Australia and Queensland borders meet.

The French Line starts at Poeppel Corner, and for the next 170km is very slow going. You're lucky to average 20kmh, as the dunes start to pile up on one another, without longer, flat stretches between. The dunes are less steep, but the track is more demanding: a series of bumps and ruts which gives the suspension a real workout.

You also see fewer other vehicles on this section, as travellers start to spread out on the tracks which run south from the French Line to the Rig Road. You are well and truly in the desert wilderness.

Another Simpson theory is that you should drop your tyre pressures below 20 pounds per square inch (psi) to cross the dunes without digging in and getting stuck. This works, but it also greatly increases the chance of a punctured sidewall, or a tyre rolling off its rim.

We ran the tyres at 25psi with no problems, and have done so on other outback trips.

Purni Bore to Dalhousie is a quick, easy run on small, hard, clay-topped ridges along the Spring Creek Delta track, which feels like freeway compared with the French Line.

As you approach Dalhousie you'll cross Gluepot Bog. If it has recently rained, you probably won't. On the western side of Dalhousie, Tenacity Bog is equally obstinate when wet.

Dalhousie Springs is the perfect spot to finish a Simpson crossing. You will by now be encrusted with red dirt; showers are provided at the camp ground, but the best bet is to first wander down to the clean, hot springs and immerse yourself in glorious water. I guarantee it will be the best tub you have ever had.

Bummer in summer
Take plenty of water: 10 litres per person per day to be on the safe side. Don't even think about doing the trip in summer. If the heat doesn't kill you, the flies will. May-September is the season – the winter months are best, but be prepared for frosty nights.

Essential kit
A GPS (Global Positioning System) unit will allow you to give your precise location if you need help in a hurry. Take two spare tyres, repair plugs, a portable air compressor and a steel or wooden base for the jack. A spare fanbelt, hoses, coolant and engine oil are worth carrying.

Fuel's gold
If you're in a large petrol-engined 4WD, you will probably double your normal consumption – 200 litres total capacity is suggested. Diesels will use less. Our LandCruiser 4.2 turbo diesel auto used 109 litres between Birdsville and Oodnadatta; the 3-litre turbo diesel Patrol used 114 litres.

The buddy system
Always travel with company. It's a lot more fun and if something goes wrong with one vehicle, you can always reach assistance in the other. Carry a snatch strap (available at any 4WD accessory store) and a shovel to aid in your recovery if you get bogged.

Paperwork
A Desert Parks Pass is mandatory for South Australia's northern parks. It costs $80, and is available at Innamincka, plus Shell and Mobil at Birdsville. The pass includes a set of maps and notes on the geology, flora and fauna. Call the Desert Parks Pass toll-free hotline on 1800 816 078.

For more information:Innamincka Regional ReservePark Headquarters (phone 0886759909), Wirrari Information Centre, Birdsville (phone 0746563300, e-mail wirrari@hotmail.com), Birdsville Pub for meals and accommodation (phone 0746563244).