Andy Green is a rock star in Bonneville. You’d expect no less, given he’s the only human to travel supersonic on land. To witness him holding court in the local, speed-obsessed speakeasy – the incomparable Carmen’s Black & White bar – is something else entirely. “I still have to buy my own beer,” he smiles, though the owner did gift him a free drink as he turned 64 on the eve of Bonneville SpeedWeek 2026.

Which makes what he’s here to do even more remarkable. Twenty years after JCB hit 350.092mph with its Dieselmax, scoring a still-standing world record for its fuel, the Staffordshire company is back to do the same for hydrogen. Hydromax aims initially to beat both its predecessor and the 348.342mph of its designated Blown Gas Streamliner class at SpeedWeek, achieved via the average of two runs in the same direction (on consecutive days) to Southern California Timing Association (SCTA) rules. A week later, once the brilliantly absurd homebrewed cars have headed home, the FIA descends on the salt flats to measure JCB’s second-gen streamliner across two tightly packed runs in opposing directions to score a world record.

The retired RAF wing commander is the ideal driver to slide into its slim cockpit. He drove Dieselmax here back in 2006 and knows the rigours of chasing record speeds with great intimacy, hitting 763.035mph in Thrust SSC almost 30 years ago. A new partner this time around is Prodrive, who alongside Ricardo and Xtrac have helped bring Hydromax to fruition in little over a year. “It’s great when you can apply the same skill sets to different environments in motor sport,” Prodrive chairman David Richards says. “There aren’t many disciplines left unticked. I’m nearly at the end of my career, I suspect. I’ll have to sit down quietly at the end of the year and see if there’s anything missing…”

What a striking thing it is too, all 9.75m and 2.5 tonnes of it. A carbon monocoque and tubular steel frame are clothed by carbon panels. Green’s services were secured early and the car is designed around him. “Not only geometrically, to fit him in,” project director Ryan Ballard says, “but the systems, the layout of the cockpit, and the menu and error messages that he gets.” Each axle gets its own digger engine as a direct power source for permanent all-wheel drive with no traction control. “Calibrating it for a salt track that changes from hour to hour is difficult,” says Ryan. “Andy’s right foot is well calibrated…”

“I’m utilising skills that are anchored in 30 years of having the world’s best day job as a fighter pilot”

A multi-million-dollar Land Speed Record attempt needs a purpose and in this case it’s promoting a future for internal combustion with genuine hydrogen digger powerplants nestled either side of the carbon cell. They share a block, crank and sump with their production donors and possess a curious mix of diesel common rail, petrol ignition and hydrogen combustion technology. Ricardo has helped double their peak revs to 4500rpm while power soars tenfold to 800bhp apiece; overall outputs are 1600bhp and 2200lb ft. Xtrac provides a six-speed sequential transmission for each engine, a clever ECU sewing everything together so that Andy pulls one set of paddles. There’s no clutch pedal and he opts not to left-foot brake.

Its Goodyear tyres were developed at a specialist aerospace facility and run at 135psi. Unlike plenty of SpeedWeek streamliners, there’s a friction braking set-up to back up the twin parachutes. Useful when Andy suffers a parachute failure early in SpeedWeek. “We’d mused whether the brakes were the most overdesigned and expensive ballast ever,” he smiles. “Then suddenly they were the best thing we invested in!”

Though Prodrive tested the car at RAF Wittering, it hadn’t surpassed 200mph before venturing upon the unpredictable surface of the salt. “The car has done the equivalent of seven laps of Le Mans,” smiles Andy. “Imagine turning up to the startline for a world-class race with seven laps of development.” The first few days of SpeedWeek don’t just centre around honing Hydromax for Bonneville’s unforgiving moonscape, but for Andy to get his eye in too. Fastest man in the world he may be, yet like all SpeedWeek drivers he must step up gradually through various speed ranges to qualify for the licence that allows him to aim beyond 350mph on the salt. That’s a mile every 10 seconds, after all.

Bonneville boggles your sense of perspective. Earth’s curvature ensures you can’t see the startline from the paddock and competitors drop out of your vision quickly. The intense heat and light reflected by its bright salt are something else, too. It’s a relentless bombardment of your senses as a spectator – never mind a member of the two-dozen crew flown across by Prodrive or the 6ft 3in driver squeezed into the Hydromax cockpit.

“It can be a disorientating environment,” admits Andy. “But I’m utilising skills that are anchored in 30 years of having the world’s best day job as a Royal Air Force fighter pilot. I also spend a few minutes before I get in the cockpit watching another couple of cars go down the track. You can learn a lot. If there’s not much salt spray, the grip’s probably quite good.”

Then there’s the refinement on board – or lack thereof. “Hard mount a pair of 4.8-litre four-cylinder hydrogen-powered engines revving at over 4000rpm to the chassis and there’s a lot of noise and vibration. But it’s also got the most enormous degree of confidence. It just feels like it wants to go. It’s a really, really beautiful bit of engineering.”

“It’s easy to get emotionally overexcited at Bonneville. I’ve seen lots of drivers do it”

Andy provides detailed commentary as he drives, adding generous meat to the bones of the engineers’ data feed. “We’re very conscious of the risk and Andy keeps us on the straight and narrow,” admits Prodrive race team principal Simon Dowson. “Saying what he’s seeing and feeling is much more helpful than just looking at the data afterwards. He’s computing it all as he goes; it’s amazing to see him travel those speeds and keep that calm.”

There are two key places to watch Andy and JCB do their thing. From the startline you see not only the pageantry of SpeedWeek play out but witness the push car propelling Hydromax from the line. Prodrive stalwart Darren Turner shoves it carefully up to 60mph with the 626bhp might of a Land Rover Defender OCTA. “I would have come to the salt flats anyway at some stage in life – it was on my list of things to do,” smiles Darren. “My job is to be gentle, as I don’t want to break traction. I also don’t want to end up breaking Andy’s traction and giving him a bit of a lateral load on the rear of the car.” Once first gear engages he drops away and Andy’s right foot stays planted to the floor until he’s nudged his run’s target speed and it’s time to extinguish the engine and pull his self-packed parachute – or stamp on the brakes…

JCB HYDROMAX

• Record 406.320mph

• Weight 2500kg

• Length 9.75m

1. Transmission Twin Xtrac six-speed sequential, four-wheel drive

2. Hydrogen consumption Around 2kg each run, emptied every 75 seconds, producing 18 litres of water

3. Ice tank/cooling system 250kg capacity, emptied each run/ every 75 seconds

4. Engines Twin 4.8-litre four-cylinder turbocharged hydrogen combustion engines, mounted front and rear within the wheelbase, 800bhp/ 1100lb ft each for 1600bhp/2200lb ft totals, max revs circa 4500rpm

The alternative is to station yourself a safe distance back from the mile four markerboards to see the yellow ’n’ black cigar dissect the sky and salt, to an accompanying sound that’s a cocktail of low-flying jet and construction site. It’s where I anchor myself to witness the theatre of Andy’s consecutive attempts on the record. As day five of SpeedWeek draws to a close, he sneaks in a 367.141mph run which sees the Hydromax impounded overnight – like all record-chasers – to allow scrutinised prep of the car ahead of its second run the following morning.

Bright and early, the surface not yet sizzled by the sun, a 369.554mph run carves out a 368.347mph average to break a 16-year-old class record by a healthy margin and earn the engineers a chance to hold an evocative Bonneville trophy aloft in the searing midday sun. Cheri Howard, a regular of the SCTA timing booth for 38 years, prints me out a receipt as a memento. “Bet I was here before you were born,” she laughs.

Four days later the salt flats host a very different atmosphere. The 20,000-odd SpeedWeek spectators have gone, their bonhomie eclipsed by a forensic focus. JCB boss Lord Bamford, now 80, has flown his whole family in by private jet to watch the record play out.

This week’s course is longer – almost the full length of the flats at 10 miles – and the engines are wound up from their 600bhp during SpeedWeek to a perkier 700bhp. Any more and the car’s cooling system would be pushed beyond its limit in the 40˚C heat. FIA scrutineers measure the course, approve the safety of Hydromax and Andy’s gear, and then it’s time. Two runs within 60 minutes in opposing directions, with the flying mile measured after markerboard five. We watch a safe distance from that precise spot.

Run one begins and an eerie hush descends. Hydromax passes, its inimitably grumbly sound notably trailing the visual; this run is rapid. It hits 230mph by mile one and scores 400.623mph on its flier before a subtle boom as its ’chute deploys. The team then turn the car around (on a trailer, given its minimal lock), refuel it from a hydrogen truck, refill its ice tank and swap on a fresh set of Goodyears, using around 40 of their 60 sanctioned minutes.

Run two. There’s a murmur around the crowd now, a cautious optimism fizzing between us. Andy passes the timing gear at 412.135mph for an FIA-stamped 406.320mph average. He later admits to nudging 419mph during one run before shutting the engines down for the measured mile, coasting through it to safely purge the engines of hydrogen. He’s unflinchingly level-headed. “It’s easy to get emotionally overexcited at Bonneville. I’ve seen lots of drivers do it.”

He exceeds team expectations in propelling Hydromax 103mph beyond any hydrogen-powered car before SpeedWeek burst into life. A fitting end to a blockbuster fortnight with a celebration at Carmen’s to wrap it all up. Andy’s due a free drink.