The first time it climbs a bank, the tyres’ sidewalls flex and the compressor whirrs away, keeping everything on an even keel. The amount of give in those massive tyres is incredible. Like a slow-motion video of a Top Fuel dragster, it looks like the rubber is constantly trying to peel itself away from the metal wheel.
In light of those short front and rear overhangs, it won’t come as a surprise to learn that ascent and descent angles aren’t an issue. The maximum uphill/downhill is 35deg and sidehill is 22deg. The former is about the same as a very steep black run on a ski slope. In other words, not something you would want to walk up.
Yet for all its capability, the Fat Truck is a remarkably simple thing to operate. Turn a key, be deafened by the noise of the Caterpillar diesel (it’s mid-mounted, just behind where you sit, and no amount of noise insulation is going to soften those dulcet tones) and you’re ready to go.
As I said, it’s operated by a simple joystick; there are no pedals. Cycle through a handbrake-release procedure by rotating a button below the control pad, press and hold a dead man’s switch on the front of the joystick (fighter jet machine gun style), push the stick all the way forwards and you’re off.
It’s exceptionally smooth and civilised (offset by the deafening engine), but the trick to controlling it is to keep the joystick pinned all the way forward for maximum revs and change the speed by using the gears. These are controlled by two simple buttons on the top of the stick – one for up, one for down.