“We had to look at how strong the chassis needed to be to support the Halo structure, so that it can do the job it needs to do,” says Mellor. “That load is similar to the loads for the principal roll structure on an F1 car, so the two were integrated, and Halo is now the secondary, forward roll structure on the car, and the test loads on it are higher than for the principal roll structure. So in addition to deflecting debris, the Halo is a very protective part of the car for dealing with incidents such as rollovers.
“The level of safety goes significantly beyond what we originally targeted.”
By way of comparison, the Halo device is stronger in the event of a rollover or object strike than the closed cockpit of a Le Mans prototype. “The limitation of the Halo is the size of the openings required for forward visibility and egress, so we looked at the risk of debris passing through those holes,” says Mellor. “The engineering of an F1 car helps here, because most parts are made of lightweight materials, so for a part to be heavy enough to cause injuries it tends to be quite large, and thus is more likely to be def lected by the Halo.”
That said, research is ongoing: the IndyCar Series in the US is continuing to look into clear windscreen-type solutions and Mellor says some form of transparent top for the Halo could be explored. The Halo could well evolve over time, but the intention for it to be used in a number of championships will limit that.
The FIA has named three official Halo manufacturers and the units will be used in F1 and F2 this year, with Formula E following in the 2018/19 season. In F1, teams can fit limited aerodynamic fairings to slightlyvary the looks.
That look, of course, has been criticised somewhat. Mellor notes that aesthetic concerns are “well above my pay grade” but he does suggest that, as with other safety steps like high cockpit supports (introduced in 1996), people will likely adjust to its looks over time.
Besides, any aesthetic concerns are countered by the Halo’s key goal: saving lives. Mellor says: “Within the risk assessment study we conducted for the Halo across many championships, it was concluded that over the last ten years there are a number of drivers who could well be alive today if the cars had been fitted with this type of device.”