Force India estimates adding the Halo to its 2018 F1 car cost up to $1 million (£710,000) as it had to develop a new chassis to accommodate it.

Technical director Andrew Green said the team would have used a development of last year’s car, a significant cost saving, had it not been required to add the new safety device.

“Expense-wise it’s huge because we had to do a new chassis,” Green told RaceFans at today’s test. “We wouldn’t have anticipated doing a new chassis this year given the amount of changes we made last year, which was huge with the regulation change.”

“For a team like us we’d try to get two years out of the chassis if possible. So in that respect it cost us a huge amount to redevelop and design a new chassis. You’re looking at hundreds of thousands if not millions of dollars to put the Halo on the car.”

Green said the lateness of the decision to add Halo to the cars for 2018 created further problems.

“It was late summer, autumn time before we actually had a specification of Halo to put on the car,” he explained. “And even then we didn’t know what the homologation test was going to be. So to try and design the chassis, not knowing what was going to be bolted to it and what loads would be inflicted on it [in the crash tests] was tough.”

Passing the crash tests was vital to ensure the team could run in Spain this week.

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“We knew we were going to end up with one shot to get it right and if we’d’ve failed we wouldn’t be sitting here now, we’d be left with a chassis and lots of bits,” said Green. “It’s a commendable effort by the team to do the job, pass first time and get us here.”

Halo also presented problems for hitting not just the minimum weight limit, but also the limitations on weight distribution, as Green explained.

“From a design perspective obviously weight is a big part of it. The weight limit has gone up but by not nearly as much as the installation of the Halo. So it put additional stress on all the other parts of the car to try to optimise the weight in those areas, keep the weight of it below the minimum so that we can run ballast.”

“The other area that we have to bear in mind is we have to hit our weight distribution target as well. It’s a small window of weight distribution you’ve got to hit so the architecture of the car has got to be correct otherwise you’re adding ballast to a car that doesn’t need ballast just to get the weight distribution right. We knew we couldn’t afford to do that. So that was a big challenge and the architecture of the car was changing right up until the last minute.”

Force India plans to introduce updated parts ahead of the first race to optimise the aerodynamics of the Halo.

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“It has a significant downstream effect especially around the rear wing area,” said Green. “It’s not designed to be an aerodynamic device but it doesn’t do us any favours in that department. It’s obviously the same for everybody but it still requires a lot of work to mitigate the issues that it causes and we’re still actively working on that. We won’t have a solution until we get to Melbourne.”

“I’m confident we’ll have it under control by then. We’ve been working on it for quite a while. This week we’ll make sure we understand the losses coming off the Halo are where we think they are in all our modelling tools. If that’s confirmed we’ve confident the parts we’re bringing to the car will sort it out.”

2018 F1 season