F1’s bosses agreed at a meeting of the F1 Commission rules-making body on Wednesday they would assess data from this final test at a further meeting to decide whether action needed to be taken in the short term.
Concern arises from the fact the new engine rules have tripled the power provided by the electrical part of the engine but left the batteries more or less the same size as last year, and removed one of the devices used to recover energy.
This had led to cars that are energy starved and forced the teams to find new ways to harvest sufficient electrical energy to produce the best performance. The rules governing energy recovery are also highly complex.
That in turn has required drivers to perform behaviours that have been described as “counter-intuitive” to optimise lap time.
These include not going flat out put of the final corner before a qualifying lap, lifting and coasting on a qualifying lap, and even not accelerating at full power at the end of a lap because it was more advantageous to use the energy elsewhere.
However, drivers have generally been positive on the handling characteristics of the new cars, and a number of top drivers all told BBC Sport they are still driving to the limit of grip, and driver ability will still be as crucial as ever.
Domenicali said: “Don’t be worried about the energy management. We’re going to solve that. If we need to solve it, by the way.”
He has spent his time in Bahrain having a series of discussions with individual drivers about the sport, including Verstappen.
And he added: “Max wants and does care about Formula 1 more than anyone else. He has a way of putting the point that he wants to say in a certain way.
“Max will be part of the future of Formula 1 and of course it’s very important that we listen to him and all the top drivers that are very important in this sport.”
Domenicali also said F1 was looking at introducing new sporting elements on Fridays, expanding on the approach that led to sprint-race weekends, which feature two qualifying sessions rather than one, and a shorter race on the Saturday in addition to the grand prix on Sunday.
He has already previously said F1 is considering increasing the number of sprint events beyond the current six.
Domenicali added: “Feedback from the fans, from the people attending the track, the promoter, [is] that people want to see action, real action during the three days.
“People want to see already on Friday something that is sporting – qualifying, points, whatever it is.
“So, it is true that there is the trend to go in the direction of, even if it is not a sprint every weekend.”
Wolff’s remarks come in the context of an ongoing row over the legality of the Mercedes engine.
Rivals believe Mercedes have found a loophole that allows them to run the engine above the permitted compression ratio.
This – a measurement of the cylinder displacement between the two extremes of the piston stroke – is limited to 16:1, and the rules dictate it will be measured at ambient temperature with the engine at rest.
Mercedes’ rivals believe they have found a way to use materials technology and thermal expansion to run the engine to a higher ratio and are pushing for a rule clarification before the start of the season next month.
Mercedes have not denied they are doing this, but insist the engine is legal.
Rivals have claimed the trick is worth as much as 0.3secs per lap, while Wolff said the gain was “a few horsepower – in England you would say a couple, which is more like two and three.”
He added: “Lobbying from the other engine manufacturers has massively ramped up over the last few months.
“I mean, secret meetings, secret letters to the FIA, which obviously there is no such thing as secret in this sport.
“Everybody was a little bit too excited about the performance of the Mercedes engine-powered teams.
“And I think that our colleagues from the other brands have been carried away a little bit that this could be embarrassing, which I don’t think it is at all.”
On the prospect of the rules changing before the start of the season, he said: “There is a governance process. And if that governance were to vote for an engine regulation change, you just have to take it on the chin.”
But he said: “The very essence of Formula 1 is to find performance, to attract the best engineers and the best people, give them freedom to develop regulations and once it goes for you and another time it goes against you.”
Williams team principal James Vowles, who is a Mercedes customer, said: “The PU that we have in the car is completely compliant with the regulations. This is a meritocracy where the best engineering outcome effectively gets rewarded as a result, not punished as a result.
“Right now, I don’t think there is a person in the pit lane that can tell you what is the best PU. We are focused on one detail.
“My hope is that sense prevails and we as a sport recognise that we are here to be a meritocracy. The best engineering solution wins as a result of it and therefore we are where we are right now.”
Weekly insights and analysis on the latest developments in military technology, strategy, and foreign policy.
The U.S. government has accused China of secretly conducting at least one “yield-producing nuclear test” in recent years despite the country having a stated moratorium on such activities. Last year, U.S. President Donald Trump announced plans to engage in new nuclear testing “on an equal basis” with China and Russia, but it remains unclear what that might mean and what action has been taken. The new test allegation also comes as American officials continue to call for a new nuclear arms control treaty that includes China to succeed the New START agreement with Russia, which sunset yesterday.
“Today, I can reveal that the U.S. government is aware that China has conducted nuclear explosive tests, including preparing for tests with designated yields in the hundreds of tons,” Thomas DiNanno, Under Secretary of State for Arms Control and International Security, said during a speech at the Conference on Disarmament in Geneva, Switzerland this morning. “The PLA [China’s People’s Liberation Army] sought to conceal testing by obfuscating the nuclear explosions because it recognized these tests violate test ban commitments.”
Then Deputy Assistant Secretary of State Thomas DiNanno seen descending into a Minuteman III intercontinental ballistic missile (ICBM) launch facility at Minot Air Force Base in North Dakota during an inspection in 2019. US State Department
China is a signatory to the Comprehensive Nuclear-Test-Ban Treaty (CTBT), but has never ratified it. The same is true of the United States. Both countries have stated self-imposed moratoriums on yield-producing nuclear testing. The CTBT does not prohibit sub-critical testing, which does not involve a full-fledged nuclear reaction. China’s last acknowledged critical-level nuclear test was in 1996. The last U.S. test of that kind was in 1992.
“China has used decoupling – a method to decrease the effectiveness of seismic monitoring – to hide its activities from the world,” DiNanno added. “China conducted one such yield-producing nuclear test on June 22nd of 2020.”
China has conducted nuclear explosive tests, including preparing for tests with designated yields in the hundreds of tons… China has used decoupling – a method to decrease the effectiveness of seismic monitoring – to hide its activities from the world. China conducted one such…
— Under Secretary of State Thomas G. DiNanno (@UnderSecT) February 6, 2026
As an aside, the last official nuclear test in Russia came in 1990, just before the fall of the Soviet Union. The United Kingdom, France, India, and Pakistan also conducted yield-producing nuclear tests at various points in the 1990s. North Korea is the only country known to have conducted such tests since 2000, with the detonation of five devices in separate instances between 2006 and 2017.
The video below offers an excellent graphical representation of the extent of known nuclear testing, covering detonations between 1945 and 1998.
A Time-Lapse Map of Every Nuclear Explosion Since 1945 – by Isao Hashimoto
At the time of writing, the U.S. government does not appear to have provided further details about the newly alleged Chinese nuclear testing. When American officials arrived at their current assessments about these activities is also unclear.
The U.S. State Department made no mention of any such testing in China in its most recent routine international arms control compliance report, published in April 2025. That report did reiterate previous U.S. accusations that Russia has engaged in supercritical nuclear testing in violation of its commitments to multiple test ban treaties, something DiNanno also highlighted in his speech today. Russia is a signatory to the CTBT and had previously ratified it. Russian President Vladimir Putin revoked that ratification in 2023 after the country’s parliament, or Duma, passed a law approving that action.
The Pentagon’s annual report to Congress on Chinese military developments, published in December 2025, also makes no mention of Chinese nuclear testing.
“They [China and Russia] don’t go and tell you about it,” Trump said. “You know, as powerful as they are, this is a big world. You don’t necessarily know where they’re testing. They — they test way under — underground where people don’t know exactly what’s happening with the test.”
“You feel a little bit of a vibration. They test and we don’t test,” Trump continued. “But Russia tests, China — and China does test, and we’re gonna test also.”
In an earlier compliance report, the State Department had raised concerns about work China was observed doing at its Lop Nur nuclear test site in 2019. That report was notably published in June 2020, the same month Under Secretary DiNanno says the PLA conducted the yield-producing test.
“China’s possible preparation to operate its Lop Nur test site year-round, its use of explosive containment chambers, extensive excavation activities at Lop Nur, and lack of transparency on its nuclear testing activities – which has included frequently blocking the flow of data from its International Monitoring System (IMS) stations to the International Data Center operated by the Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization – raise concerns regarding its adherence to the ‘zero yield’ standard adhered to by the United States, the United Kingdom, and France in their respective nuclear weapons testing moratoria,” the report explained.
Following Trump’s interview in November 2025, Chinese authorities had pushed back and reiterated the country’s stated commitment to its moratorium on nuclear testing.
“China notes that the U.S. continues in its statement to hype up the so-called China nuclear threat. China firmly opposes such false narratives,” Chinese Ambassador Shen Jian, Deputy Permanent Representative of the People’s Republic of China to the United Nations Office at Geneva and other International Organizations in Switzerland, said today following Under Secretary DiNanno’s remarks, according to Reuters. “It (the United States) is the culprit for the aggravation of the arms race.”
It should also be pointed out that the United States and Russia are both generally assessed to have roughly 4,000 warheads each. The U.S. figure has been declining in recent years, while the Russian one has been growing, according to the Federation of American Scientists (FAS) think tank in Washington, D.C.
As noted, successive U.S. administrations have been pushing for a new nuclear arms control regime that includes China. Negotiations in the past have focused more heavily on bilateral agreements with Russia, and the Soviet Union before it. The most recent of these deals, New START, expired as scheduled yesterday, following the conclusion of a one-time five-year extension. There are still unconfirmed reports that the U.S. and Russia may be working on an interim and non-legally-binding arrangement to keep the New START limits at least for some amount of time, as you can read more about here.
“New START was signed in 2010 and its limits on warheads and launchers are no longer relevant in 2026, when one nuclear power is expanding its arsenal at a scale and pace not seen in over half a century and another continues to maintain and develop a vast range of nuclear systems unconstrained by New START’s terms,” Under Secretary DiNanno also said in remarks today. “[China’s] buildup is opaque and unconstrained by any arms control limitations.”
“Rather than extend ‘NEW START’ (A badly negotiated deal by the United States that, aside from everything else, is being grossly violated), we should have our Nuclear Experts work on a new, improved, and modernized Treaty that can last long into the future,” President Trump had written yesterday on his Truth Social platform.
Trump:
Rather than extend “NEW START” (A badly negotiated deal by the United States that, aside from everything else, is being grossly violated), we should have our Nuclear Experts work on a new, improved, and modernized Treaty that can last long into the future. pic.twitter.com/MPlDNeTWLZ
“The President’s been clear in the past that in order to have true arms control in the 21st century, it’s impossible to do something that doesn’t include China because of their vast and rapidly growing stockpile,” U.S. Secretary of State and acting National Security Advisor Marco Rubio also said during a press conference on Wednesday in response to a question about New START.
SECRETARY RUBIO: The President has been clear that in order to have true arms control in the 21st century, it’s impossible to do something that doesn’t include China — because of their vast & rapidly growing stockpile. pic.twitter.com/FiYVUsBAVb
Chinese officials have repeatedly rebuffed calls to join negotiations on a new nuclear arms control agreement.
The allegations Under Secretary DiNanno raised today prompt new questions about the future of U.S. nuclear testing, as well. As mentioned, there has been little elaboration on exactly what President Trump meant by his announcement last year about future testing “on an equal basis” with Russia and China. At that time, U.S. Secretary of Energy Chris Wright had downplayed the possibility of a resumption of American yield-producing nuclear tests.
“Since the President’s statement, we have received many questions about what he meant,” DiNanno said during his speech in Geneva today, before diving into the accusations about Chinese and Russian tests. However, the Under Secretary did not explicitly say whether or not this meant the United States intends to conduct its own testing at this level going forward. He did say later on in his remarks that the U.S. government is committed to efforts to “restore responsible behavior when it comes to nuclear testing.”
You can read more about what it would actually take for the U.S. government to resume full-scale nuclear testing in this previous TWZ feature.
The end of New START has already been fueling renewed concerns about a new nuclear arms race, and one that would not necessarily be limited to the United States, Russia, and China.
Following today’s revelations in Geneva, more details at least about the new U.S. allegations about Chinese nuclear testing activities may begin to emerge.
Update: 1:50 PM EST –
In light of today’s remarks from Under Secretary DiNanno, the Comprehensive Nuclear-Test-Ban Treaty Organization’s (CTBTO) Executive Secretary Robert Floyd has issued a statement.
”The CTBTO’s International Monitoring System (IMS) is capable of detecting nuclear test explosions with a yield equivalent to or greater than approximately 500 tonnes of TNT, including detecting all six tests conducted and declared by the DPRK [North Korea]. Below 500 tonnes is roughly 3 percent of the yield of the explosion that devastated Hiroshima,” Floyd says. “Mechanisms which could address smaller explosions are provided by the Treaty but can only be used once the Comprehensive Nuclear-Test-Ban Treaty enters into force. That is why it is important that the nuclear arms control framework includes the entry into force of the CTBT. The need is more urgent now than ever.”
“Regarding reports of possible nuclear tests with yields in the hundreds of tonnes, on 22 June 2020, the CTBTO’s IMS did not detect any event consistent with the characteristics of a nuclear weapon test explosion at that time. Subsequent, more detailed analyses have not altered that determination,” he adds. “Any nuclear test explosion, by any state, is of deepest concern.”
“Speaking of amazing technology, we successfully used a shipboard laser system, Lockheed Martin’s HELIOS, to knock an incoming UAV [uncrewed aerial vehicle] right out of the sky,” the company’s CEO Jim Taiclet said during a quarterly earnings call last week. “The HELIOS weapon system successfully neutralized four drone threats in a U.S. Navy-operated counter-UAS [uncrewed aerial systems] demonstration at sea, showcasing an opportunity to eliminate drone attacks using lasers, and saving U.S. and allied air defense missiles for more advanced threats.”
A picture taken from the bow of USS Preble in 2024. The HELIOS laser is seen mounted on a pedestal right in front of the main superstructure. USN
TWZ reached out to Lockheed Martin, the prime contractor for HELIOS, for more information and was directed to comments from Navy Vice Adm. Brendan McLane at the Surface Navy Association’s (SNA) annual symposium in January. McLane is the commander of Naval Surface Force, U.S. Pacific Fleet. As the Navy’s top surface warfare officer, he is also often referred to by the title SWOBOSS.
“The Surface Navy has a rare opportunity with leadership aligned on delivering lethality, capability, and capacity at speed. As an enterprise, we must continue to think big as we develop the future platforms within the world. We must lay the foundations for the systems on those ships now so that they deliver on their promise to the American people,” McLane had said at the SNA conference. “Continued iteration with USS Preble’s HELIOS laser weapons system is another example of this. Last fall, successful at-sea testing paved the way for future laser weapons systems. We need to continue on this path. I am committed to advancing laser technology to the fleet. The dream of a laser on every ship can become a real one.”
TWZ has also reached out to the Navy for more information.
HELIOS, which also carries the designation Mk 5 Mod 0, is a 60-kilowatt-class laser directed energy weapon designed to be powerful enough to destroy or at least damage certain targets, such as drones or small boats. As its name indicates, it has a secondary function as a ‘dazzler’ to blind optical sensors and seekers, which could also be damaged or destroyed in the process. In the past, Lockheed Martin has talked about potentially scaling HELIOS’ power rating up to 150 kilowatts.
A close-up look at the HELIOS laser installed on the USS Preble. USN
A multi-target scenario is a logical evolution in the demonstration of HELIOS’ capabilities. The Navy’s experiences during operations in and around the Red Sea in the past few years have underscored the challenges defenders face at sea and on land when responding to large volume drone attacks. Uncrewed aerial systems layered in with other threats like anti-ship ballistic and cruise missiles present even more complexities. The potential for traditional air defense capabilities to be overwhelmed is real. The level of complexity will only increase as artificial intelligence and machine learning-driven capabilities, including automated targeting and fully networked swarming, keep proliferating globally.
This all presents cost benefits, too. As an example, the latest versions of the RIM-116 Rolling Airframe Missile (RAM), used for point defense on many Navy ships, each cost around $1 million.
USS Porter Conducts SeaRAM Test Fire
Many warships across the Navy are also equipped with Mk 15 Phalanx Close-In Weapon Systems armed with six-barreled 20mm M61 Vulcan rotary cannons, but the ammunition for those weapons is not unlimited, either. Each Phalanx has enough ammunition to fire for a total of around 30 seconds, at most, at the lower of two rate-of-fire settings, before needing to be reloaded. Many ships across the Navy also have a mixture of other guns, including 5-inch or 57mm main guns, as well as 25mm or 30mm automatic cannons, all of which can also be used against close-in threats.
Phalanx CIWS Close-in Weapon System In Action – US Navy’s Deadly Autocannon
There are still significant questions about the demonstration last fall, including how rapidly the USS Preble was able to shift HELIOS from one target to another and how long it took each one to be effectively neutralized. The proximity of the drones to the ship and what kinds of profiles they were flying are also unknown.
A single laser can only engage one target at once. As the beam gets further away from the source, its power also drops, just as a result of it having to propagate through the atmosphere. This can be further compounded by the weather and other environmental factors like smoke and dust. More power is then needed to produce suitable effects at appreciable distances. Adaptive optics are used to help overcome atmospheric distortion to a degree. Altogether, laser directed energy weapons generally remain relatively short-range systems.
A graphic depicting an Arleigh Burke class destroyer firing a HELIOS laser. Note that the beam would not be visible to the naked eye during a real engagement. Lockheed Martin
In addition, laser directed energy weapons, especially sensitive optics, present inherent reliability challenges for use in real-world military operations. Shipboard use adds rough sea states and saltwater exposure to the equation. There is also the matter of needing to keep everything properly cooled, which creates additional power generation and other demands.
“You know, we have continuous electron beam, free electron lasers today that can scale to megawatt-plus, gigawatt-plus [power ratings],” Navy Adm. Daryl Caudle, Chief of Naval Operations, told TWZ and other outlets at the Surface Navy Association’s (SNA) annual symposium last month. “I’m telling you that I don’t think a one-megawatt laser is beyond what should be on that battery [on the Trump class].”
A rendering of the first Trump class “battleship,” to be named USS Defiant, firing various lasers, missiles, and other weapons. USN
Beyond the Trump class, “this is my goal, if it’s in line of sight of a ship, that the first solution that we’re using is directed energy,” Caudle also said. “Point defense needs to shift to directed energy. It has an infinite magazine.”
“What that does for me is it improves my loadout optimization, so that my loadout, my payload volume is optimized for offensive weapons,” the Navy’s top officer added. Furthermore, “as you increase power, the actual ability to actually engage and keep power on target, and the effectiveness of a laser just goes up.”
Challenges to the Navy’s directed energy future clearly still remain. In speaking last month, Caudle was optimistic for the future, but he has been open about difficulties in the past. At the SNA symposium in 2025, the admiral, then head of U.S. Fleet Forces Command, said he was “embarrassed” at the state of his service’s directed energy weapon developments.
“I am not content with the pace of directed energy weapons,” Vice Adm. McLane had also said back in 2024. “We must deliver on this promise that this technology gives us.”
This is reflective of broader difficulties that all branches have faced in the development and fielding of laser directed energy weapons, in particular, for use in the air and on the ground, as well as at sea, as you can read more about here.
What we do know is that the Navy continues to use the USS Preble to prove out the HELIOS system, including with the recently disclosed demonstration of its drone-zapping capabilities last fall.
The car has now passed all its impact tests, Vowles added, and drivers Carlos Sainz and Alex Albon “stand shoulder to shoulder with me”.
“They’re clearly, as I am, disappointed,” said Vowles.
“They want to be out there testing the car, and whilst they’re in our driver and loop simulator in tandem now, to increase that programme, it isn’t the same.”
Vowles said the main problem was the factory was unable to cope with the demand put on it by the car build process.
“It’s more of an output than anything else, of pushing not just the boundaries of design but the boundaries of just simply how many components can be pushed through the factory in a very short space of time,” said Vowles.
“The car we’ve built is about three times more complicated than anything we have put through our business beforehand.
“So, to put that in perspective, it means the amount of load going through our system is about three times what it used to be.
“And we started falling a little bit behind and late on parts. There are compromises you can make as a result of it.
“In addition to that, we have absolutely pushed the boundaries of what we’re doing in certain areas. And one of those is in certain corresponding tests that go with it.”
However, he said the team were on target to make it to the second pre-season test, which takes place in Bahrain on 11-13 February.
Vowles added: “We could have made Barcelona testing. Simple as that. But in doing so, I would have to turn upside down the impact on spares, components, and updates across Bahrain, [the first race in] Melbourne, and beyond.
“And the evaluation of it was that for running in a cold, damp Barcelona, against doing a (rig) test, against the spare situation, and frankly, there was zero points for running in a shakedown test, we made the decision, and I stand by it, that the right thing to do is to make sure we’re turning up at Bahrain, correctly prepared, and prepared in Melbourne as well.”
Vowles did not directly answer a question as to whether the car was significantly over the minimum weight limit, saying it was impossible to respond to “murmurings in the media” because it was not possible to know the answer until the car was assembled.
He also said he had “experts and specialists” working with Williams to try to improve their factory operations.
Seven of the 11 teams were running on Monday – Red Bull, Mercedes, Racing Bulls, Haas, Alpine and the new Audi and Cadillac teams.
McLaren said last week that they would not take their car on to the track until after day one as a result of trying to maximise design time. Ferrari, after an initial test at their factory last week, had also announced they would not run on Monday.
Aston Martin have said their new car will not be ready until Thursday, and Williams are missing the test entirely after delays to their design and production programme.
No times were issued, and all teams ran into at least some technical issues as they learned about their new cars.
Rival teams were impressed by the amount of mileage the two Red Bull teams managed considering it was the first full day of running with their new in-house engine, which has been developed in conjunction with new partner Ford.
Before the test started, McLaren and Red Bull revealed images of their 2026 cars for the first time.
McLaren, who won the drivers’ and constructors’ championship double last year for the first time since 1998, showed the car in the one-off testing livery it will run in this week.
Red Bull showed studio shots of their car, carefully chosen to disguise key design features.
Russell added: “We are pleased with our day, but I’ve also been impressed by several other teams.
“The Red Bull power unit has completed a lot of laps which, given that it’s their first engine they’ve built, means they’ve clearly done a good job.
“Haas also managed a similar amount of running to ourselves, so the Ferrari power unit has also put together plenty of mileage. It’s not quite how it was in 2014! The sport has evolved so much since then and the level, in every single aspect, is so high now.”
Audi have taken over the Sauber team for the German car company’s first entry into F1. They suffered a reliability issue that prevented Bortoleto driving in the afternoon.
Team principal Jonathan Wheatley said: “We had a technical issue, spotted it and decided to switch the car off. Plenty of testing this year and wanted to really understand the problems, see what the weather conditions are and decide whether we run tomorrow.”
Rain is forecast for Tuesday’s second day of the test, during which teams are permitted to run on a maximum of three of the available days.
Bortoleto said: “The cars are very different. I feel these are going to be slower but it’s very cool to have the power unit being 50% electric – you go out of the corner and you have so much speed being deployed and you can see how strong the engine is.
“You need to adapt but it’s still a racing car.”
Racing Bulls’ Lawson said: “[The car is] very different to drive and I haven’t got my head around it fully yet. We will keep learning. It feels like there is a lot more we can do as drivers to make a difference, potentially, but right now it’s very early days, very hard to know where we are for now just trying to optimise the car.
“[The power unit] feels good. But it’s very hard to tell – the main thing is reliability at the moment.
“We have done a good amount of laps today and the only issues we had today were safety precautions, not actual issues. But hard to know where we’re at compared to everyone else.”
