Bankstown-based AMSL Aero is well on the way to the first hydrogen-powered flight of the Vertiia eVTOL. CEO Chris Smallhorn and Director Business Development Tim Cadman spoke to Australian Flying about development progress.
AMSL Aero is a home-grown company with its sights fixed on the emerging Advanced Air Mobility (AAM) industry. In particular, their target is regional air mobility sector, which envisages connecting regional cities with urban facilities via long-range eVTOLs.
The company plans to do that by rolling out their Vertiia eVTOL. Vertiia is a hydrogen-electric vectored-thrust aircraft that will get both lift and propulsion via eight tilting rotors. AMSL believes the Vertiia will be ideal for passenger and cargo transport to and from regional cities, and aeromedical services.
At the time of writing, Vertiia is still in development, but the path to certification is getting progressively shorter. AMSL is talking about civil certification sometime in the 2029-30 financial year.
"We've completed our first two flight test programs," AMSL CEO Chris Smallhorn told Australian Flying. "The first one was in 2023, which was tethered hover only, and in December last year we completed a three-month test program at Wellington in NSW, which was untethered hover or free flight and the low speed envelope.
"Both test programs were highly successful. As one of only five or so companies in the world in this sector who have flown, AMSL Aero are very proud of the achievements. More than 100 flights is serious progress."
But unlike the conventional fixed- and rotary-wing industries where standards are established and practices tried and trusted, there is virtually nothing about eVTOL development that isn't new. Furthermore, those technologies are new to each other, so integration can take a lot of trial and error.
"In VTOL terms, one of the first phases of the flight test program is to confirm safe vertical take-off and landing qualities," Smallhorn points out. "Next is to confirm safe performance across the low speed envelope. Sometimes you can have 10-15 knot winds or you have to re-position the aircraft to a take-off or landing area; all of that is the low-speed end of the flight envelope.
"As a general rule, any speed less than 40-50 kt is the low-speed envelope. We tested the aircraft flying across the full low speed envelope around the 360 degrees of flight direction; forward, backwards, sideways flight. We did a series of modifications to the aircraft over about a year using the same prototype that did the tethered hover test, which then completed the second free hover and low-speed test program..
"The Q4 2024 test program exceeded all of our expectations in that we planned the aircraft to fly to only 50 kt, yet there was still plenty of torque available in the design, so we ended up flying it out to 60+ kt. That was 20% above what we planned."
The holy grail of eVTOL development is successful transition from vertical flight to horizontal flight in a stable and safe condition. As there are many different eVTOL designs, the mechanisms for achieving that are different. But rather than rush to the gate, Smallhorn and his team have focused Vertiia on getting the low-speed manoeuvring right.
"This first prototype aircraft was not designed to go into the transition flight," he explains. "The first prototype was about getting the hover and low speed envelope flight envelope cleared, characterised, and safe. That’s done now.
"Vertiia proved to be very easy to handle for the Test Pilot, who was flying via a mobile remote cockpit at the test field for initial safety of flight reasons. That's important, because when you're in an aircraft it's generally easier to control it because you're connected to it; you become part of it and you see what's happening in front of you in real time."
A critical part of the long-range capability is the hydrogen-electric power cell. For the distances Vertiia is designed to cover, batteries just won't cut it. However, all Vertiia flight testing to this point has been done on batteries; things can go wrong in experimental flight and batteries are cheaper than fuel cells.
"We're now building prototype number two, and we're well along the way of building the first hydrogen-electric power pod," Smallhorn says. "That prototype will fly in Q2 next year, and at that point we intend to do transition flights as well as fly the aircraft on our AMSL Aero hybrid-hydrogen power pod.
"We will fly flight-test vehicle two on hydrogen, but we won't fly the whole test program on hydrogen. The main reason is that we don't actually have to fly for long periods of time in the initial phase of the flight test to gather the data, so we didn't need range or endurance extension at the time."
Vertiia's short-range cousins that will work the Urban Air Mobility (UAM) routes around Australia's metropolitan areas will most likely rely solely on battery power, topped up by strategically-positioned recharge stations. Vertiia, however, is destined to work mostly from established airports.
"Our strategic partnerships are very important to us, and one of those is with Archerfield Airport who aim to lead the Queensland airport in being hydrogen ready for aviation; another key part of the ecosystem," Smallhorn says.
"Archerfield, Essendon and Bankstown are prime examples of non-major airports that are inner-city. Having infrastructure hubs in places like that is super important, because when you put a 1000-km circle around out major cities, it covers a lot of Australia. Being able to know that you can access a point in an inner city is really important."
Partnerships are also important with customers. From the first conception of AAM and eVTOLs, developers sought commitment from stakeholders in terms of in-principle agreements and letters-of-intent (LOI). It took vision and a touch of courage for companies to sign up for a future yet to be made, but sign they did.
For AMSL, linking up with Aviation Logistics subsidiary Air Link was milestone moment.
"AMSL Aero's first Vertiia customer is AirMed, they are major part of our story," Smallhorn says. "An amazing Australian company the group of service providers–AirMed, AirLink and Air Log–provide air capability to a massive part of Australia interconnecting regions and communities.
"They have joined us in our shared vision of giving the best access to all the communities across our vast country, and to do so cheaper and with zero emission.
"When we talk about eco-systems we are an OEM; we don't intend to be an operator. The operators have as much skin in the game as the OEM if not even more, because at the end of the day that's how they're going to make their money. Trust is ultimately our currency."
The hazy economics behind UAM adds a level of uncertainty to the viability of AAM as a whole, but the sort of missions Vertiia will be deployed on don't rely on the same cost structure or the establishment of new, specialised infrastructure.
AMSL Director Business Development Tim Cadman believes much of the support network for Vertiia is already in place, adding some certainty to the business plan.
"A green zero-carbon emissions mobility solution is something that we have to do," he stresses. "We are doing this with one aircraft design that can meet civil and commercial applications, support emergency services such as air ambulance and remote firefighting and support defence missions. It's a true multi-mission aircraft.
"From an infrastructure perspective, we don't have the same challenges or dependencies on a larger network of high-voltage recharge locations to meet regional operational outcomes."
Progess on Vertiia is well advanced, but that doesn't mean the road thus far has been easy. Vertiia is perhaps the most complex aircraft ever developed in Australia and has relied upon technological expertise the equal of anything anywhere in the world. In that, the Vertiia roll-out is also a showcase for Australian innovation and skill.
"I see this as true nation-building stuff," Smallhorn says. "When a nation starts to do this at the leading edge of technology, we become one of the world leaders. There are about a hundred eVTOLs in development around the world, but Australia is one of only about half-a-dozen nations that have got one airborne.
"To get the average Australian to understand how special that is isn't always easy.
"This is what sovereign industry looks like; this is showcasing Australia to the world."