Christmas road test: stunt plane

Every Christmas Autocar road tests a vehicle with a difference, and this year's offering is one of the most nimble, wacky and fun yet: the XtremeAir Sbach 342, a state-of-the-art aerobatic plane for those with strong stomachs.

The Sbach is world’s first all carbonfibre aerobatics aeroplane. In car terms, it's like something out of the World Rally Championship, because just as a WRC car is easy to drive, so the Sbach is not particularly difficult for an amateur to fly.

See the test pics of the XtremeAir Sbach 342

You could fly it to Goodwood for a cup of tea or to the south of France on holiday, but if you put a pilot of great ability in the cockpit, quite remarkable feats can be done with it. Here, we experience something equally otherworldly with Gerald Cooper, British Unlimited Aerobatics champion and ranked seventh in the world.

Below are some of the highlights of the test:

Design and engineeringUp front we have an American Lycoming AEIO-580 six-cylinder aero engine. That’s 580 cubic inches, so a mighty 9.5 litres in our money. But you won’t be impressed by the power output because this monster motor produces only 320bhp at 2700rpm.

On to the front of the engine is bolted a three-blade MT propeller with 80in blades. That’s a big old prop for an aircraft with an empty weight of only 635kg, but you need big blades to put all that torque to work.

InteriorYou fly the Sbach 342 solo from the rear seat. The view is better, but the main reason is that it has less effect on the balance of the aeroplane. In the front cockpit, you are provided with only the basic controls that you need to fly the aircraft.

Both occupants sit on their parachutes and are strapped in by a five-point harness fitted with a ratchet system to tighten the harness to medieval torture levels of tightness. The view out through the canopy is fantastic, which is essential in aerobatics and for general flying about the place. You don’t need a great deal of room in a sports ’plane, just as you don’t in a supercar, but the 342 doesn’t feel cramped and there’s far more elbow room than in a Caterham.

PerformanceOpen the throttle slowly at first because if you whack it open the torque reaction of the prop will send you off course, as will the propwash flowing down the side of the fuselage. By light aircraft standards, the acceleration is astounding. By car levels, 0-60mph puts it into the very brisk sports car category.

But once we’re rolling, the figures become more impressive: 0-100mph in 8.9sec is the same as an Aston DBS. The numbers compare but the sensation is totally different. By light aircraft standards, the acceleration is astounding.

See the test pics of the XtremeAir Sbach 342