- More than 55 % of the body structure features high-strength and ultra-high-strength steel, ensuring occupant safety.
- Lightweight body structure boosts fuel economy.
- All Fiesta models are equipped with a dual front airbags. Sport models include side and curtain airbags and driver knee airbag as standard equipment.
- Antilock Brake System (ABS) and Electronic Brake-force Distribution (EBD) is standard on all derivatives.
- PowerShift models are equipped with Electronic Stability Program (ESP), Traction Control, Hill Hold and Hill Launch Assist (HLA) and a gradient assist function.
Under the stylish exterior of the new Ford Fiesta is a powerful body structure that can protect occupants in the event of a collision. More than 55% of the body structure is high-strength steel, including dual-phase steel and ultra-high-strength aluminised Boron steel.
The Fiesta’s shape is designed to provide added protection, and the car is both rigid and stiff torsionally, surrounding occupants with a secure, safe cabin.
Although its body structure has been beefed up, the overall weight remains modest. Safety improvements have not compromised fuel economy or efforts to limit CO2 emissions.
Ford’s safety strategy employs high-strength steels to reinforce areas of the vehicle that are essential for crash protection. These include the floor structure, front rails and beams, and an ultra-rigid, integrated body-side reinforcement ring to protect against a side impact.
High-strength materials are used to create a stiff B-pillar section and a stiff rocker section fore and aft. This disperses the force of a side impact collision laterally to the opposite side of the car via chassis cross members. The integrated body-side reinforcement ring also helps dissipate the force of front and rear impacts, and resists intrusion in case of a side impact.
Crash performance was evaluated using advanced computer simulation technology before real crash tests took place. The simulation allowed engineers to determine where performance issues may need to be addressed in the development stage, not in prototype.
Elements of the body-side reinforcement ring include:
- A-pillar – The A-pillar forms the forward part of the vehicle’s stylish roof arch. Fashioned from ultra-high-strength aluminised Boron steel, it delivers the strength and rigidity required for crashworthiness. The materials allow designers to keep the pillar slim and maintain driver visibility.
- B-pillar – Another boron steel component, the Fiesta B-pillar reinforcement is shaped for maximum strength. The pillar helps resist intrusion and retain structural integrity in side impacts while helping the vehicle maintain its shape in other types of crashes.
- Rocker panels – The B-pillar is fastened to the rocker panels, or lower rails. They are crafted from very-high-strength dual-phase steels renowned for their energy absorption properties.
- Rocker baffles – To optimise side impact protection, uniquely shaped twin-shear baffles are welded to the inside of the rocker panels. They help stabilise the rocker section to ensure optimal safety in the event of a side impact.
- Side roof arch – Another dual-steel component, the side roof arch connects to the A-pillar for strong overhead protection. The side roof arch ties into the top of the B-pillar.
- Lower A-pillar – The lower A-pillar is formed of very-high-strength, dual-phase 600-grade steel.
These high-strength elements are manufactured into an integrated sub assembly before they are joined to the vehicle in the body shop of the production line. This new process ensures better joint strength and greater precision.
Even more high-strength steel
More high-strength steel can be found in other parts of the Fiesta’s body structure. Dual-phase steel front frame rails and side rails feature structural actuation points, called trigger points, to initiate predictable collapse in crush zones. By forming the “triggers”, this hardens the dual-phase material giving it the unique ability to both absorb and resist the force of an impact.
The front of the rail is a crush zone but to avoid overloading the backup structures, the rail is designed to bend and counter-bend while still offering very stiff resistance against further intrusion. This is called a ‘crush-bend-bend-bend’ strategy.
Fiesta’s under-floor structural beams, so-called ‘sled runners’, are also formed from dual-phase steel as are lateral reinforcements that are designed to manage side impact forces.
The extensive use of dual-phase steels allowed the Ford body engineering team to develop new techniques. Since the dual-phase steels gain strength after stamping, the team worked to quantify how much added strength contributed to the overall body structure.
Defining the ultimate strength of the assembly helped Ford’s sophisticated crash simulation computers to accurately predict, or ‘map’, how the components would perform in the event of a crash. To help support the use of high strength steels, advanced manufacturing techniques were employed,
including the use of new robotic welding heads.
Intelligent Protection System (IPS)
As part of Ford’s Intelligent Protection System (IPS), all Fiesta models are equipped with driver and passenger airbags. The Sport model features seven airbags (dual front, side and curtain airbags and driver knee airbag) as standard equipment, which earned it a five-star Euro NCAP safety rating.
Part of Ford’s IPS technology includes extensive airbag sensor calibration testing. Engineers worked to ensure that the airbags are activated quickly and deployed in appropriate circumstances.
Three-point safety belts with dual-stage digressive load-limiting pre-tensioners are standard for both front seat occupants. In the rear, three-point safety belts are provided for the two outboard passengers. The retractors pull the safety belt tightly to position the occupant ideally for airbag effectiveness.
Dual-stage digressive load limiting features allow for a slight reduction in belt tension to reduce the possibility of a chest injury in the event of a crash. Adjustable head rests optimise whiplash protection and front seats feature an anti-submarine design.
For additional driver safety, a special carpet underlay called a crash pad is placed between the floor panel and carpet to minimise impact to the lower leg during a crash. A safety belt reminder system is standard and reminds the driver to buckle up before driving.