McLaren cause stir with paint-heavy F1 car and ‘human wall’

McLaren caused a stir at the end of the opening day of 2025 F1 pre-season testing in Bahrain.

Lando Norris headlined the first of a three-day pre-season test by setting the pace at Sakhir following an hour-long delay caused by a circuit-wide power outage.

But Norris also grabbed attention for his final run of Wednesday when he emerged from the McLaren garage with his car almost completely decked in neon green flow-visualisation dye.

F1 teams use flow-vis paint to help better understand how air flow is working over their cars, and it has become a common sight at pre-season testing.

However, the sheer amount used by McLaren raised eyebrows in Bahrain.

“That is a lot of flow-visualisation dye and in fact, if they put any more of that on [Gabriel] Bortoleto will be getting the cockpit thinking its the Sauber there was so much green dye on that car” F1 technical expert Sam Collins said.

“We’ll get a bit of an idea at how that air flow is working over that McLaren. Now that’s the drawback to using flow-visualisation techniques like that in an open test, you are not just showing yourself where that stream is flowing over the bodywork, you are also showing your rivals and all of us what’s going on.”

Fellow F1TV pundit Alex Brundle, son of former F1 driver Martin, commented: “I’m amazed they’ve done that, actually, with everyone in the pit lane, photographers all around the circuit.

“The full aero concept for everyone to see in flow. Sure, you give away a sidepod or a little bit of the front suspension, but the lot is going to be quite a photograph for the rest to be looking over.

“Especially for the car which will end the first day of 2025 pre-season testing fastest.”

Norris was seen fighting his car at Turn 4 and Turn 10 as he conducted a single lap run before returning to the McLaren garage. One of his wing mirrors was even obscured by the volume of flow-vis paint.

On his return to the pit lane, a large number of McLaren employees formed a “human wall” around Norris’s car to to block the view from prying photographers and cameramen.

“They are all surrounding this car, to prevent anyone from taking close up photos or really high quality film footage of all of this flow-dye down the side of the car, because they are desperate to stop other teams from seeing all of this information they are giving away,” Collins explained.

Some crew members stopped a photographer from taking photos by jumping up in the air and waving their hands in front of his camera.