If you could see past the dry ice and lasers the Valo, the aircraft Vertical Aerospace intends to bring to market, was surprisingly beautiful. The rough edges – metaphorical and literal – of the VX4 prototype have been sanded off, leaving an elegant aircraft which, when viewed from the side, has an oddly piscine silhouette.
Unveiled at a gathering in London’s Canary Wharf on 9 December – the heart of the city’s financial district – the Valo “builds on everything we have learned from our previous aircraft”, Vertical chief executive Stuart Simpson told the packed audience.
Sprinkled in with the razzamatazz was some obligatory dawn-of-an-electric-age hyperbole. Simpson made the economic case, arguing that the Valo represents a multi-billion-dollar opportunity for the UK, returning the country “to the forefront of aircraft manufacturing”.
Chairman Domhnal Slattery, meanwhile, calls the arrival of electrical vertical take-off and landing (eVTOL) aircraft aviation’s next milestone moment after the dawn of the jet age.
“It’s not simply a new aircraft, it’s a new idea of what human ingenuity can make possible. Moments like this are a reminder of why aviation matters,” he says.
“Electric flight is not going to remain on the margins; it will reshape how the world moves.”
Well, you get the idea.
Besides the sleek new low-drag profile, the Valo – a Finnish word meaning ‘light’, as in bright – also gains a new passenger cabin capable of seating four people, rising to six within two years of service entry, and a best-in-class luggage bay.
Detailed as it was, the Valo revealed in London was just a mock-up: the real thing will not take to the skies before 2027, one of seven aircraft to be used for the certification campaign.
“It’s not just an improvement on the VX4 but an improvement on all the products on the market,” says Simpson.
Customer demand has driven the insistence on the large interior and luggage bay, he says, adding: “I’ve had so many people come up to me and say: ‘We have sat in all the others, but this is the one we are actually going to buy’.”
Aircraft performance should also be improved by the changes, derived from the thousands of data points gathered from the ongoing VX4 flight testing.
Thanks to the reshaped fuselage, the Valo’s wetted area, and therefore drag, is 20% lower than that of the VX4. Wingspan grows by 1m (3ft) and the wing itself gains a slight anhedral, while the tips outboard of the final electric motor pylon are now removable too. And, at 10.6m tip to tail, the Valo is also significantly shorter the 12.3m-long VX4.
Although the arrangement of the eight-propeller propulsion system remains as it was – and the wing is broadly the same shape – the pylons have been aerodynamically resculpted.
On top of which, the front four propellers go from a five- to a four-bladed design for weight and drag reasons. The blades themselves have a slightly narrower chord, reducing solidity and weight, and lose their anhedral profile, which “makes them easier to build”, says chief engineer David King.
Perhaps the most obvious change is at the rear of the aircraft, where the V-tail morphs into a Y-tail. The structure sits lower than on the VX4, while the tip of the Y acts as both a ventral fin, offering “a little bit more lateral directional stability”, and a fairing for a new tail wheel.
In turn, that sees the previous tricycle landing gear dropped in favour of the new configuration with the main gear tucked away in fairings on the outside of the main fuselage.
Chief test pilot Simon Davies says the VX4’s nose-gear arrangement necessitated structural reinforcement to the fuselage – by changing the configuration, the main gear sits directly below the wing, optimising structural paths through the fuselage bulkhead and minimising weight.
Additionally, says King, the changed layout enables better distribution and balance of the underfloor battery packs, improving accessibility and shifting the Valo’s centre of gravity.
Vertical argues that storing the batteries below the fuselage rather than in the wing offers several advantages: “Wing-mounted batteries require much heavier wing and fuselage structures, add weight through access panels, and compromise aerodynamics,” it says.
“Under-floor batteries are easier to access, simpler to upgrade, better for centre-of-gravity control, and reduce inertial loads. They also avoid solar heating and keep high-voltage cabling short and safe.”
The Valo’s batteries will also be ugraded over those on the VX4, using a liquid- rather than air-cooled design, cutting their weight by 20%.
Overall, King says, the combined airframe and battery updates result in a 15% lower take-off mass than the VX4.
Of course, the Valo has not convinced everybody: those sceptical of distributed electric propulsion eVTOLs as a concept remain unmoved – Robinson Helicopters’ David Smith is a notable critic – while sector champions, among them Mark Moore, chief executive of Whisper Aero and voluble eVTOL commentator, describes the redesign as a “step backwards” and a “Lilium-like play to push towards sexy appeal, instead of a real aircraft designed to get through certification and into production”.
Moore’s initial take is that the Valo has two particular problems: its propulsion system is not arranged to minimise the threat of a cascading blade failure – a problem that caused the loss of Vertical’s first VX4 prototype – and that the landing gear lay-out will not allow the aircraft to meet US Federal Aviation Administration certification criteria requiring it to perform a conventional landing in case of complete power failure.
“Vertical’s new concept has no ability to do a conventional landing at a reasonable angle of attack because of tail-wheel strike,” he writes.
Writing in a reply to Moore, Vertical’s chief commercial and strategy officer Michael Cervenka points out that the propellers are “canted to avoid adjacent propeller impact risks and to improve hover stability” and the overall system has been designed to comply with European certification requirements “including cascade-failures”.
He also notes that while the European Union Aviation Safety Agency’s certification standards do not require the aircraft to be capable of an unpowered landing, it can nonetheless perform a low-speed landing at around 45kt (83km/h).
“The tail landing gear is designed to absorb energy in the unlikely event of a nose-up flare landing,” he adds, noting a similar design on the Sikorsky S-70 Black Hawk helicopter.
Moore also argues that the cabin will not be able to accommodate six people in a VIP layout and still offer any meaningful range. To be fair to Vertical, this is not something it is proposing: the Valo will launch with a 550kg (1,210lb) payload and the proposed six-seater is seen as an airline shuttle-type cabin, with luxury seating distinctly absent; Vertical also concedes there will be a payload-range trade if more passengers are carried before the next generation of batteries arrive in 2030.
King says a derivative of the baseline Valo – whether the six-seater or a hybrid-powered variant – will follow within around 12 months of the initial certification, a milestone targeted for 2028. Whichever variant is not the first selected will then arrive around a year later.
Simpson, however, is clear: “The hybrid will probably be first as there’s so much demand for it,” he says.
Vertical’s hybrid powertrain is due to fly later next year following installation on the developer’s third prototype.
But first, that aircraft – G-VTLB – needs to complete its maiden sortie: King says proof-load testing and calibration of instruments were completed earlier in December, opening the path to a first flight in the coming weeks.
For his part, Davies cannot wait: “It’s an exciting time: having more than one prototype flying really feels like we are growing up as an aerospace company.”
In the meantime, the company continues to progress the existing VX4 prototype (G-EVTA) towards a crucial full transition flight. “We have made really good progress – we are really near,” says Davies.
While that goal is still at the mercy of the British weather, he remains hopeful it can be achieved by year-end.
Although the location of the unveiling ceremony was partly dictated by the lack of suitable venues elsewhere in the capital, it was no accident that it ended up in Canary Wharf: for all Vertical’s ambitions and technical progress, it is still a company markedly less well capitalised than its big US rivals and needs access to some of the cash currently sloshing around the nearby investment banks and other financial institutions.
As of 4 November, the company had $117 million in cash and cash equivalents – enough to keep the lights on until the second half of next year.
Simpson does not seem overly concerned, however: funding will be “step by step”, he says. “We don’t feel any pressure as we stand here now. We are in the best position this year the company has ever been in.”
Indeed, Simpson says he is “more confident than ever” that his September prediction that certification can be obtained with further investment of less than $700 million is still achievable.
But that does not mean he is passively waiting for this to happen: Simpson is working to secure “a long-term strategic partner” – be that industrial or financial – within the next 12 months.
“That’s the number one priority,” he says. “I’ve spent two weeks out of the last five in the UK – I’ve been going around the world conducting due diligence on potential partners.”
In the meantime, the clock is ticking towards the point in mid-2026 where Vertical will have to decide where to locate its high-volume production line, a facility supposed to come on stream in 2030.
“We have got a shortlist,” says Simpson, although declines to be more specific.
And while there is a desire to keep Vertical in the UK, he says the government “has got to help us”, noting that at least three other countries and 12 US states have approached the business offering inducements to locate.
“We need to make it British and keep it here, but when other countries write to me and offer incentives we have to listen.”
In the short-term, however, Vertical has committed to the UK, pledging to build the seven Valo pre-production assets and initial customer aircraft at its site at Kemble airfield in southwest England.
Tooling has already been commissioned for the outer mould-line of the first Valo pre-production aircraft and final assembly should begin in late 2026, King adds.
Ross Crawford, Vertical’s vice-president of operations and manufacturing, says work is under way to expand its existing footprint at Kemble – the home of its flight-test operation – taking on a third hangar and constructing another building. “It will give us quite a significant amount of space,” he says.
