New territory for Zone RV

The latest and greatest example of what's possible from innovative Queensland caravan company Zone RV, has just set off on a 12 month, around Australia durability trial.

Unveiled at last month’s Queensland Caravan & Camping Supershow, the futuristic Zone RV Z-19 A/T ‘prototype’ is a smorgasbord of the latest  design and technologies, including some adapted from the marine, trucking and aeronautical industries.

Nicknamed ‘Bobby Dazzler’ by owner Peter Richards, the slick, 19ft van features a unique, all-aluminium off-road chassis matched to a similarly lightweight, semi monocoque fibreglass composite body from Coolum-based Zone RV.

With a unique tapered I-beam (or ‘H’-shaped) A-frame evolving into a large diameter main chassis, it features bespoke alloy trailing arm tandem axle independent suspension, self-levelling airbag springing and wads fitted with hydraulic disc brakes.

After struggling to find a large caravan that suitably blended light weight with off-road durability, Richards turned to former Golf Caravans’ production manager and specialist aluminium fabricator, Ken Vaughan, who currently runs Limit Seeker camper trailers in Brisbane, to design and build the chassis.

With a drawbar modelled on an aeroplane wing strut and four, 120 litre water tanks slotted neatly beneath the main rails, the alloy chassis weighs 700kg, or around 300kg less than a steel chassis of equivalent strength.

The unique suspension is also designed to reduce stress on chassis components, with a longer, 730mm trailing arm and more vertical, 'up-down' movement of the airbag springing, compared to other off-road suspensions available.

“There’s less stress on our frame compared to a more conventional set-up, due to the way we’ve got the shock placement," he said.

Along with Zone RV’s unique interlocking, 'Tufflite' body construction, significant weight savings were achieved by using featherweight but strong laminated composite panels normally found in multi-million dollar yachts for interior cabinetry.

“You save another 300-400kg in the furniture. There’s no weight in it; it’s like fairy floss,” Richards said.

Also borrowed from the top-end boating industry is the 25mm rubber and vinyl ceiling 'padding' that provides additional noise and temperature insulation.

Since its Queensland show debut, Richards has ditched the three, 120Ah AGM batteries for two, more efficient 100Ah lithium batteries from Revolution Power Australia (along with a Redarc lithium battery charger) to cut a further 140kg.

Combined with four of the latest Chinese-built 100W roof solar panels weighing just 1.8kg each and a Powertech 180W pure sine wave invertor, it’s enough to run the Waeco 12V 215 litre compressor fridge, Daewoo wall-mounted washing machine and microwave.

Fitted with “everything that opens and shuts”, the van also features a Truma gas/electric water and air heater, internal and external TVs, and a Thetford fan-forced oven and cooktop.

Tare weight is currently around 2000kg, or about 500kg less than most off-road caravans of its size. With an ATM of 3500kg, this allows for an impressive 1500kg payload.

“What I set out to do is to build a full off-road van and get the best possible suspension and then build something that was strong and adequate and keep the weight down,” Richards said.

As a ‘test bed’ for the latest ideas and products, he’s also trialling some aerodynamic body tweaks adopted from research conducted in the trucking industry, to improve fuel economy.

“We put an aerofoil (on the back of the roof) to provide a jet curtain down the back to get rid of some of the drag and also to keep the back cleaner," he explained. "But on top of those I’ve also got square tips if you like, they’re about 25mm square cubes, and they act as vortex generators to break the vacuum over the top.”

So far, it’s been towing “really well” behind a Holden Colorado dual-cab ute, achieving a best of 15.5L/100km on the highway.

Combining business with pleasure, Richards and his wife plan to spend 12 months completing a ‘Big Lap’ of Australia, taking notes along the way in order to deliver a ‘report card’ on the van at completion.

However, with the chassis alone costing $20,000, there's a price to pay in reducing both weight and energy consumption.

“Pricewise (the van) compares to a (top-spec) Kedron, so you’re looking at about $140-$150,000 with the aluminium chassis,” he said.