All F1 cars were painted in fluorescent colors during testing – the real reason behind it. During the Bahrain F1 pre-season tests, teams applied fluorescent paint to cars for aerodynamic flow analysis. .

During the Bahrain pre-season Formula 1 tests, many observers noticed a curious detail that was far from purely aesthetic: several cars hit the track with large areas covered in fluorescent paint. This choice immediately drew the attention of photographers and fans, particularly around the diffuser, rear wing, sidepods, and suspension. However, behind that bright color lies one of the most important tools for aerodynamic development: flow viz.

What is flow viz and why do teams use it in testing

Flow viz, short for flow visualization, is a special fluorescent paint mixed with oil, applied to the aerodynamic surfaces of the car. During laps on track, the airflow moves the paint, creating visible streaks that allow engineers to observe the actual behavior of the air around the car with great precision.

This technique is essential for verifying the correlation between CFD data, wind tunnel results, and on-track performance. Key areas analyzed include the diffuser, beam wing, rear wing, and floor – all crucial zones for generating downforce under the new technical regulations.

Crucial Bahrain tests for data collection

During the two Bahrain test sessions, held from February 11–13 and February 18–20, data collection was central to every team’s program. With the introduction of the new technical regulations, on-track values are not yet fully defined, and teams prioritized understanding aerodynamics over chasing outright performance.

The widespread use of flow viz fits exactly into this process: engineers examine potential flow separation, vortex quality, and floor efficiency to optimize updates before the start of the season.

Early signals from testing: reliability and performance

Among the teams that impressed with reliability, Mercedes stood out, completing a long series of laps and maintaining high dependability – a key factor for continuously collecting data. Ferrari also has reason for optimism: Charles Leclerc posted the fastest overall time, and the start simulations showed encouraging results, with positive signs for Ferrari-powered teams as well.

The situation was more complex for Honda, which, following delays during the January shakedown in Barcelona, faced several reliability issues. These problems inevitably limited mileage and, consequently, the amount of data collected – a particularly delicate issue during the early phase of a completely new set of regulations.

Fluorescent paint is a technical tool, not just aesthetics

The fluorescent paint seen on the cars is therefore not a cosmetic detail but an essential technical instrument. The more regulations change, the more crucial it becomes to understand in detail how air flows around the car, and flow viz remains one of the most effective methods to do so directly on track.