Beginning in 2012, IndyCar began using a single chassis supplier in hopes of controlling and limiting costs, improving safety, and to manage competition. This was the start of Indy Racing League's new ICONIC Plan (Innovative, Competitive, Open-wheel, New, Industry-relevant, Cost-effective) and the introduction of a new automobile, replacing the 2003/2007-model Dallara IR-05 with its naturally aspirated V8 engines (in use since 1997). Manufacturers who submitted proposals for the new chassis designs included BAT Engineering, Dallara, DeltaWing, Lola and Swift.
On July 2010 it was announced that the IndyCar series had accepted the Dallara proposal, with the core rolling chassis known as the 'IndyCar Safety Cell'. The Italian manufacturer Dallara built the DW12 (also known as the Dallara IR12) was built for the 2012 IndyCar Series serving as a replacement for the prior Dallara IR-05 chassis. The chassis was named after Dan Wheldon, who was killed at Las Vegas Motor Speedway in October of 2011, the final race of the previous IR-05. Wheldon had also performed the first official test of the Dallara IR12 at Mid-Ohio on August 8th of 2011. Each chassis had a fixed cost of $349,000 per chassis.
The chassis was designed to accept various aerodynamic kits, but the introduction and use was delayed until 2015, with Chevrolet and Honda providing the alternatives to the Dallara aerodynamic package kits.
The teams outfitted the chassis with separate body work known as 'Aero Kits' which included sidepods, engine cowlings, and wings. The Aero Kits, which were open to any manufacturer, had a price cap of $70,000. A discount was applied when the complete Dallara safety cell and aero kit were acquired through Dallara.
The Chevrolet Aerokits and Chevrolet engines won all but 6 races during the 2015 season. Due to flipping incents of Chevrolet powered teams at the 2015 Indinanpolis 500, domed skids were re-introduced to the series for the 2016 season. To prevent loose bodywork and increase safety, Zylon bodywork tethers were added to the cars. Honda made several changes to their aerokit, including the removal of the stacked triple front wing to a simpler dual element section, with a new endplate. For the road courses, new sidepods could be added which helped improve handling and performance. These changes worked resulting in the Chevrolet Aero Kits being less dominant.
A development freeze was implemented for the 2017 season in anticipation of the new IR18 Universal Aerokits. All cars were to be run using identical aero kits starting in 2018. The base Dallara safety cell design remained mostly unchanged with several components, including the rear-wheel guards and airbox were removed. The cockpit section used the new Cosworth CCW MK2 steering wheel and the new Configurable Display Unit 4.3 display dashes.
The new cockpit protection system was called the 'Advanced Frontal Protection' and made its debut in 2019 at the Indianapolis 500.
by Dan Vaughan