Ford B-Max concept

One of the key features of concept cars has always been a spacious cabin with a completely open side. Of course, the difficulty has always been that to get this kind of design you have to remove the B-Pillar, which normally divides the front and rear doors, reducing the strength of the car in side-impacts and also affect chassis stability.

So far, then, few cars manufacturers have attempted to go down this route, with the Mazda RX-8 probably the best example. However, this car has its limitations, with the small 'suicide' door at the rear only able to be opened after the front door.

With the B-Max, Ford has a different approach and one that doesn't have the same kind of limitations. We were on hand at a preview event to take a look at the small car with the big doors, as Made in Chelsea's Cheska Hull modelled the B-Max.

Made in Chelsea's Cheska Hull shows how easy it is to get in and out of the B-Max

It's the doors that will attract the most attention on the B-Max, as they provide wide an easy access into the car, using a smart new system. The front doors open as with any car, but the rear doors slide back and project slightly past the rear bumper when fully opened. It's key that the rear and front doors can be opened independently, making the B-Max every bit as easy and practical to use with rear passengers as a standard four- or five-door car.

The rear doors slide back and slightly protrude at the rear of the car

It's the engineering that's gone into the design that's particularly clever, as it's not only practical but designed to be as strong as a regularly-designed car. To get that strength, Ford has used high-tensile strength Boron steel in the edges of the doors, so that when they're shut they reform the B-Pillar. The company is confident that this should allow the car to get a maximum five-start NCAP crash rating.

Boron steel in the sides of the door combine to reform the B-Pillar, which should give the B-Max a five-star NCAP rating.

Boron steel has been used elsewhere in the car, too, including at the front of the car. This will protect occupants in the car from head-on collisions.

Boron steel at the front of the car provides strength and protection from head-on collisions.

It's the sense of space that this system gives that's particularly impressive. Without the B-Pillar in the way, getting in and out of the rear seats, or even loading larger items this way, is incredibly easy. The rear seats fold flat, extending the boot space to give plenty of room for flat-pack furniture or other heavy loads.

With fold-flat seats, there's plenty of room inside the car for large loads.

In recent years Ford has been heavily focussing on the technology that comes inside the car, such as with the New Ford Focus, which can park itself and brake automatically in emergencies. It should be no surprise, then, the B-MAX should have a whole bunch of goodies in it, too.

The test model that we saw had a small LCD screen mounted in the dash, which was playing a video. MyFord Touch, the integrated entertainment, internet, satnav and phone synchronisation system, should be in the car from launch later this year. No other announcements have been made, but we wouldn't be surprised if the automatic parking and braking systems from the Focus make it across as well.

MyFord Touch will be available on the B-Max

As the B-Max is designed to be the ultimate city car, fuel consumption is incredibly important. For this reason, the car will be available with a 1.0-litre EcoBoost engine. This is a turbocharged engine, giving the acceleration benefits of a larger engine, with the fuel economy of a small powerplant.

From the neat-looking futuristic interior to the smart new doors, the B-Max is certainly a completely different type of small car and one of the most interesting that we've seen. Due to be officially unveiled at Mobile World Congress next week, we'll bring you more information as soon as we have it.