Breakdown fears: New Formula 1 cars begin testing behind closed doors

The journey into the unknown is not without its share of pitfalls.

For the 10 new cars which begin testing in Spain on Monday, the start to a brand new era of Formula 1 begins amid concerns that they could actually break down. Hence, the public and the media have been excluded from the private testing session over the next five days. It's hard to imagine a bigger contrast to last year's lavish launch party with 16,000 fans and celebrities in London.

F1 has an 11th team this year as Cadillac makes its debut, but only 10 will be in Spain after Williams faced delays getting its car ready.

There won't be TV coverage, except brief clips from F1's own broadcaster, or official results from the five-day test this week, so it'll be hard to fathom who's got a head start on F1's new regulations. The second test in Bahrain next month is when the focus switches to performance.

In case you are wondering why F1 is blocking fans from seeing the new cars on track, it’s because of concerns that some all-new designs might not be reliable enough to make a positive first impression.

F1 originally referred to this week's event as a "private test" but now calls it the "Barcelona Shakedown," a term usually used for short-distance runs to check basic reliability, not the sort of multi-day extended tests in Spain.

Some teams, like Ferrari, have revealed 2026 designs and given them brief track time using exemptions for distance-limited promotional events, but plan major changes before the first race in Australia in March.

Defending champion McLaren is unusual for signaling its Barcelona design will be close to race specification. McLaren will skip Monday's running "in order to give as much time as possible to the development of the car," team principal Andrea Stella said last week.

Others, including Red Bull, had until now only showed new paint jobs on imitation cars, making the first runs in Barcelona an especially crucial stage in development.

So are the reliability concerns legitimate?

With all-new engines, battery systems and smaller, lighter cars, reliability is a bigger concern than it has been for years.

According to the rules, teams can run on three out of five days in Spain, giving them time to fix problems without losing ground, so McLaren's delayed start isn't a setback.

The last time the rules changed this much, the first preseason test was a disaster.

Cars broke down frequently on the first day of testing at the remote Jerez circuit in 2014 as teams got to grips with the new turbocharged hybrid V6 engines, and Lewis Hamilton beached his Mercedes in a gravel trap. The problems eventually shook out over the season and Hamilton ended the year as champion.

With reliability the main issue to be addressed in Spain, performance of the cars will be more closely monitored and more open to the public in Bahrain next month.