© 2026 New Atlas
Aircraft

AltoVolo gets a prototype of its spicy high-performance eVTOL in the air

By Abhimanyu Ghoshal
May 04, 2026
AltoVolo gets a prototype of its spicy high-performance eVTOL in the air
AltoVolo's redesigned its high-performance eVTOL concept for longer hover time and an easier pathway for pilots to legally fly it
AltoVolo's redesigned its high-performance eVTOL concept for longer hover time and an easier pathway for pilots to legally fly it
View 5 Images
AltoVolo's redesigned its high-performance eVTOL concept for longer hover time and an easier pathway for pilots to legally fly it
1/5
AltoVolo's redesigned its high-performance eVTOL concept for longer hover time and an easier pathway for pilots to legally fly it
A render of the view in the Sigma's cockpit
2/5
A render of the view in the Sigma's cockpit
The Sigma now seats two instead of three, so Sport Pilots can legally fly with a passenger after just 25 hours of training
3/5
The Sigma now seats two instead of three, so Sport Pilots can legally fly with a passenger after just 25 hours of training
The 1:4 scale Sigma prototype during a test flight
4/5
The 1:4 scale Sigma prototype during a test flight
The updated Sigma retains the stunning styling of the original design, but has swapped out the closed rotors for open ones
5/5
The updated Sigma retains the stunning styling of the original design, but has swapped out the closed rotors for open ones
View gallery - 5 images

The last time we heard from the UK's AltoVolo, it only had renders of its grand vision for a sportscar equivalent of an eVTOL to show off. That was exactly a year ago – and it's now got a working prototype taking to the skies.

The London-based firm has built and flown a 1:4 scale prototype of its Sigma aircraft, which keen observers will note looks drastically different from the previous concept we saw in 2025.

It's sticking with the previous targeted range of 500 miles (804 km) and top speed of 220 mph (354 km/h). That's faster than the five-seater Joby Aviation flew between JFK Airport and New York City's heliport network (200 mph or 322 km/h) as part of an air taxi demo last week. If it can hit these figures, the Sigma will be among the fastest eVTOLs you'll be able to board in the next couple of years.

AltoVolo Flies Sigma Prototype

You can see the scaled-down Sigma prototype in the air in the short video clip above. AltoVolo claims it's successfully completed the preliminary design review as well as testing of this early version, ahead of full type certification.

The updated Sigma retains the stunning styling of the original design, but has swapped out the closed rotors for open ones
The updated Sigma retains the stunning styling of the original design, but has swapped out the closed rotors for open ones

Look closely, and you'll notice the design has evolved to a two-seater configuration, down from three. The company says this allows it to be flown by anyone with a Sport Pilot certificate and only 25 hours of training, during the day and with fair weather conditions. This expands the potential use cases for this vehicle – and I imagine it increases room for your luggage.

The Sigma now seats two instead of three, so Sport Pilots can legally fly with a passenger after just 25 hours of training
The Sigma now seats two instead of three, so Sport Pilots can legally fly with a passenger after just 25 hours of training

The other big difference from the previous renders is you've got open rotors for takeoff and cruising, instead of closed electric ducted fans. AltoVolo says it found this switch allowed for double the hover time, quicker propeller loading, and weight savings – and it's developed its own fixed pitch propeller that's better suited to this vehicle than alternatives available off the shelf.

The 1:4 scale Sigma prototype during a test flight
The 1:4 scale Sigma prototype during a test flight

The next step is to produce the full-scale Sigma demonstrator, which will really test the design and engineering that's going into this vehicle. AltoVolo hasn't revealed a time frame for this, but we've seen it take some other companies a year tor more to get to that stage.

A render of the view in the Sigma's cockpit
A render of the view in the Sigma's cockpit

It'll then have to ace transition flight tests, pass aviation certification requirements, and get its manufacturing pipeline in order before it can begin rolling this out to high-flying customers who want the quickest short ride in the sky.

Source: AltoVolo

View gallery - 5 images

Tags

AircrafteVTOLHybrid eVTOLsPersonal eVTOLs
24 comments
Abhimanyu Ghoshal
Abhimanyu Ghoshal
Abhimanyu has been a trusted voice in the science, technology, transport innovations, startup and AI spaces for more than a decade at several global outlets, including three and a half years as the managing editor at TNW. He holds a Bachelor of Arts in Economics, Psychology and Sociology. When he's not writing about breakthroughs in science and tech, he's usually out motorcycling around South India.

Sign up for our FREE daily New Atlas newsletter!

More stories like this:

Quarterhorse 2.1 rolling out
Aircraft
Quarterhorse 2.1 takes flight on way to beating 50-year-old SR-71 record
Aerospace startup Hermeus has taken another step toward challenging the Lockheed SR-71 Blackbird’s legendary supersonic speed record as the company’s uncrewed Quarterhorse Mk 2.1 lifted off from Spaceport America in New Mexico on March 2, 2026 for its maiden flight.
The DART AE missile
Aircraft
Australia launches 3D-printed, Mach 8 hypersonic missile from US soil
Australia's Hypersonix Launch Systems has made a historic launch of its next-generation DART AE hypersonic aircraft from Wallops Island, Virginia. Taking off aboard Rocket Lab's HASTE launch vehicle, the DART AE reached a top speed of Mach 8.
The Cyclone drone in forward flight mode
Aircraft
Video: Semicircular wings give Cyclone VTOL a different kind of lift
We've seen lots of designs for vertical take-off and landing vehicles over the years, but none are quite as striking as the wings on HopFlyt's Cyclone. The curved wings have their root in a design first introduced in the 1920s but never employed in a commercial vehicle.
New superfuels promise to significantly increase aircraft and missile ranges
Aircraft
New “superfuel” promises 32% boost in aircraft and rocket range
CycloKinetics, a US propellant company, has unveiled a new family of superfuels for aircraft, missiles, and rockets that increase fuel performance by 32%. Aimed at the defense market, the fuels could allow vehicles to fly farther while carrying heavier payloads.
Unither’s hydrogen helicopter completes its first real circuit flight, opening the path to certification
Aircraft
First hydrogen helicopter just proved it can fly a real mission
A modified Robinson R44 completed the first-ever hydrogen helicopter circuit flight in Quebec, Canada, clearing a key hurdle toward FAA and Transport Canada certification for zero-emission organ delivery aircraft.
The PROTEUS uncrewed experimental aircraft alongside the ISTAR research aircraft
Aircraft
Video: Shape-shifting, flapless wings trialed on experimental aircraft
Imagine looking out the window of an airborne airplane and seeing the wing rippling and twisting. You'd probably have a mini heart attack. Yet, this is what German engineers have created: prototype morphing wings that change their shape mid-flight.
24 comments
dan
eVTOL aircraft have a basic energy problem. Even the best batteries today only store about 400 Wh/kg, while jet fuel (Jet A1 or SAF) has about 30 times more energy per kilogram. This eVTOL needs around 200 Wh/kg to fly. If about half of its total weight is batteries, it can only fly for roughly one hour. There is no realistic way it can fly 500 miles as claimed – that’s not serious.
dan
On top of that, there are major safety questions: - How is it protected against bird strikes? - What redundancies exist if one or more systems fail? - What happens in a full power failure? - Is there any life‑saving system for low altitudes below parachute deployment height (e.g. below ~500 ft)?
Also, scaling from a 1:4 model to full size is not straightforward. Mass grows with the cube of the scale (4³ = 64), while lift grows only with the square (4² = 16). So a model that flies says very little about whether the full‑scale aircraft will work safely and reliably - or even fly at all...
Overall, this project seems to rely heavily on wishful thinking rather than realistic engineering and safety considerations.
Jonathan Sterling
Insane flight footage! Love the HyperTOL term. 👏 👏
Jonathan Sterling
Dan, this is a hybrid aircraft. The parachute can work from 50 meters. Maybe have a look at their website to understand what the Sigma is all about before commenting with your knowledge. Sounds like you are a helicopter guy :)
michael_dowling
With those colorful lights,nighttime reports of UFOs will no doubt soar if this thing is approved.
HokenPoke
@DAN
As usual You’re oversimplifying the physics and drawing the wrong conclusion. (its a typical fossil fuel myth posted month after month)
Yes, Jet A1 has vastly higher chemical energy density than batteries. But that’s not the whole system. Electric propulsion is dramatically more efficient (often ~85–90%) compared to gas turbines (~30–40%), so the usable energy gap is much smaller than the headline “30×” figure suggests.
More importantly, your numbers are cherry-picked and a bit dated:
Current aviation-grade batteries are already in the 250–300 Wh/kg range, not some distant theoretical value 400 Wh/kg isn’t fantasy — it’s actively being demonstrated and targeted this decade And crucially: design studies show you need ~300–600 Wh/kg for ~300 km range aircraft — which is exactly the regime eVTOLs are targeting, not long-haul airline missions
So no serious program is trying to build a 500-mile, fully loaded, VTOL airliner on today’s batteries. That’s a strawman.
Also: range claims aren’t always “hover for an hour then cruise.” eVTOL mission profiles are optimized — vertical phases are short, cruise is wing-borne (much more efficient), and reserves/regulations differ from what you’re assuming.
And the industry reality backs this up:
Most certified or near-certification eVTOLs target 20–250 mile missions, not 500 They’re designed for urban/regional hops, where batteries are already “good enough” Longer range concepts often assume next-gen batteries or hybridization, not today’s packs
So the real situation is: Yes, energy density is the core constraint Yes, batteries are far worse than jet fuel per kg No, that doesn’t make eVTOLs non-viable And no credible program depends on 500-mile pure-electric VTOL flights today
Bottom line: This isn’t a physics violation it’s a mission-design problem. eVTOLs work in a narrow, well-defined envelope. Step outside that (like 500 miles VTOL), and yeah it breaks. But that’s not what the industry is actually building.
HokenPoke
As to Dan's second post it seems after decades you STILL haven't learnt anything whatsoever wrt EVTOL's not eben the basics.
So therefor you’re jumping to “therefore it won’t work,” which doesn’t follow.
On safety:
Bird strikes: This isn’t new territory. Certification standards like FAA Part 27 and FAA Part 23 already require impact tolerance. .
Distributed electric propulsion actually helps here multiple smaller rotors mean less single-point catastrophic failure compared to one big turbine or rotor. Redundancy: Most serious eVTOL designs (e.g. Joby S4 or Archer Midnight) use multiple independent motors, controllers, and battery packs. Losing one doesn’t mean losing the aircraft that’s the whole point of the architecture. Full power failure: Same as helicopters you don’t just “fall out of the sky.”
Many designs aim for controlled descent via glide or autorotation like behavior (depending on rotor type). It’s a design requirement, not an afterthought. Low-altitude emergencies: Parachutes (like those used by Cirrus SR22) are only one solution. eVTOL safety concepts lean more on fault tolerance and controlled landing capability, because urban ops don’t give you the luxury of parachute envelopes anyway.
On scaling:
You’re quoting the square cube law correctly, but applying it too simplistically.
Yes, mass scales with volume and lift with area if geometry stays fixed. But real aircraft don’t scale like toy models:
Full-scale designs change rotor size, disk loading, structure, and materials Reynolds number effects actually make small models less aerodynamically efficient than full-scale aircraft That’s why aerospace uses subscale prototypes + simulation + wind tunnel testing, not naive geometric scaling
If scaling worked the way you imply, no aircraft would ever go from model to full scale which obviously isn’t the case.
What’s actually fair criticism:
Range claims can be optimistic Battery limits are real Certification will be hard and slow
But “it flies as a model, therefore the full-scale probably won’t fly” isn’t a serious engineering argument, it ignores a century of aerospace development practice.
Bottom line: There are real constraints here, but this isn’t “wishful thinking.” It’s an incremental extension of existing rotorcraft + electric propulsion + redundancy engineering. The question isn’t whether it can work at all, it’s how well it performs within a limited envelope, and whether it can meet certification.
Lamar Havard
There's already too many accidents just going forward and backward...
HokenPoke
@ lamar Harvard Where ? I have not ever seen a proffesional manned Evtol crash ever, on the contrary I've seen 1000s of planes and helicopter on the ntsb list, heck theres a permanent show on sateleite TV aircraft investigations about just that !
spyinthesky
Tilt rotors have a pretty awful safety record relative to industry norms yet no one is giving up on rotor craft, they are learning, developing and improving these designs, EVtols are far more organically safe in my view even though there will be many hurdles to overcome as they are still at the early stage by comparison. In reality we are at the start of a very long term evolution and the logic of negativity would have been far more understandable in the early years of aircraft development in my view. Let’s judge in a decade rather than righting off people who clearly have some understanding of the complexities of the process and betting their money upon it.
Load More