Every McLaren road car since the vaunted F1 has featured carbon-fiber monocoque construction. With the Artura, McLaren has finally brought the entire design, prototyping, and production of this vital component in-house. Here’s how that, and the introduction of a spanking-new ethernet architecture, are making the McLaren Artura a better supercar.
In-House Carbon-Fiber Monocoque Weighs Less
This new McLaren Carbon Lightweight Architecture (MCLA) is the first to be built in-house at the McLaren Composites Technology Centre (MCTC) near Sheffield in northern England. The MCTC opened in 2018, and this completely in-house development program is paying off with a carbon-fiber monocoque that incorporates four new carbon materials, a new resin loading system, and a new structural core material, specifics of which have not yet been fully disclosed. We do know that even as late as the prototyping phase, revisions to the way the resin is injected into the carbon-fiber mold resulted in a savings of 4.4 pounds.
Doing More With Less
The Artura’s tub is designed to integrate a safety cell for the 7.4-kWh lithium-ion battery pack and fuel tank as well as meet ever-tightening crash safety standards and incorporate new aerodynamic surfaces. So, while it resembles carbon tubs that have come before it, the geometry of every surface is new. The MCLA monocoque is taller around the A- and B-pillar regions than those of previous McLarens to allow the carbon structure itself to bear loads that were previously handled by bonded metal parts. The windshield surround is carbon fiber, and the rear sides of the monocoque are extended to provide protection for the battery and fuel tank.
Nevertheless, the new tub weighs just 181 pounds—up only modestly from that of the original MP4-12C tub, which weighed about 165 pounds. The company has several patents pending on technology developed for the new MCLA monocoque.
Carbon-Fiber Monocoque Aero Tricks
Carefully beveling “chamfered” corners into the trailing edges of each front wheel arch helps the air to flow out of the arches and along the underside of the doors, so that surfaces molded into the door outer panels can trap the air, ensuring it flows rearward into intakes for the high-temperature radiators.
The Artura marks the debut of several technologies at McLaren, including advanced driver-assistance systems such as radar-enhanced adaptive cruise control, over-the-air software updates, and Pirelli Cyber Tire tire-monitoring technology. None of these features is particularly new, but they’re just being added now, in part because adding them via conventional copper wiring threatened to add too much weight. But by adopting the industry’s first “zonal domain-based ethernet architecture,” the total amount of traditional copper wire cabling is reduced by 25 percent, which dropped the mass of the electrical system by more than 10 percent and helped offset the weight of adding those established technologies.
Four central controllers positioned in key areas around the car control nearby loads and systems, with data shared over the central backbone that is this twisted pair ethernet network, with overall processing power increased substantially. The system is said to be future-proofed to allow new features to be added more easily, including over-the-air.
Another big change is the complete separation of the heating and air conditioning functions from the engine. A new eHVAC system is designed to function completely independently, its electric compressor, condenser, and evaporator all being located in the front of the car to improve weight distribution and reduce the amount of plumbing traversing from the front to the back of the car. And yes, even the heating is always provided by a positive temperature coefficient electric heater (then again, how often are these driven in weather demanding winter tires?). This type of system ensures that the cabin (and the battery pack itself, which is refrigerant cooled) can be maintained at comfortable temperatures while driving on electric power alone. Even the cabin ventilation is new, featuring a diffuse vent running horizontally across the dashboard. This design reduces the air velocity and noise for increased comfort, especially during silent electric running.