Similar to aviation giants such as Airbus, a small group of students in the Netherlands is pursuing the dream of hydrogen-powered flight. Rahiq Ullah, the team manager for AeroDelft in the 2021-22 academic year, goes into the details.

Tell us about Aerodelft and how it came to be.
“AeroDelft was founded in 2018,” Ullah tells us. “It is a non-profit organisation developed to pursue projects in the aviation sector—a space where students studying applied sciences could start projects and innovate in aviation. The organisation pursued several avenues before committing to Project Phoenix in January 2019. It is a very ambitious project that works to prove and promote liquid hydrogen as an alternative to conventional fuels in aviation.”

Can you expand on your role within the organisation?
“I am the team manager, which means I lead the management team at AeroDelft. Some of my other functions include upholding AeroDelft’s mission and vision, representing AeroDelft at various events and ensuring a good working environment within the team. We have a pyramid-like structure, but since we are a student team, we all see each other as equals. In the defined hierarchy, I would be on top and then you would have two technical managers and one operations manager. Since we have two aircraft, a prototype and a full scale, each technical manager acts as a project manager on each of them.”

“The operations manager leads our non-technical departments,” Ullah continues, “such as exposure, legal, partnerships, events, and graphics. They generally oversee operations. As for the rest of the team, it combines full timers and part timers. We have 20 full timers and 37 part-timers. The full timers usually take a gap year between studies, which is my case specifically. It’s why I can work full time while the part timers do this next to their studies. Students do this on their own time.

This is not an activity that grants financial contributions, university credits, or compensation. Team members are purely driven by their passion and enthusiasm for what AeroDelft is trying to achieve.”

What are your primary funding sources as a team composed of students exclusively?
“We do get this a lot because students are not known for having a lot of money, Ullah tells us. “The initiative started with only two full timers and an idea, but slowly and steadily more students became interested. As more students began joining, the research evolved, and more companies put their trust in us. Since we are and intend to remain a non-profit organisation, we operate with a series of sponsorships and partnerships.”

“These partnerships range from bronze to platinum, which defines the depth of the collaboration. Contributions from companies can take many shapes—financial, technical, in-kind, and knowledge sharing—and we’ve managed to keep our project thriving with these. Across these partnerships, our core mission remains to prove our concept works and promote it to inspire big companies. A considerable advantage we enjoy in terms of costs is having the manpower. More students are interested every year.”

Since commercialisation is not in AeroDelfts scope, they really have to focus on design and innovation, which atends to attract very inspired and passionate students. This has given them the advantage of being very focused and agile in what they do and one of the primary reasons companies are keen to collaborate with them. They get direct access to a pool of motivated and accomplished students. Among other things, many companies look at AeroDelft as an excellent place for their recruitment purposes.

“Of course, partnerships also include exposure and networking,” Ullah continues. “This goes both ways because we are really working on very innovative concepts, and hydrogen aviation is still a niche. There are only a few other companies I can think of in this space so far such as H2Fly and ZeroAvia, but as the only student team, we are unique in the industry and to companies.”

What is your relationship with TU Delft?
“AeroDelft is founded and run by students. We are a separate entity from the TU Delft. This being said, the university is one of our platinum partners, which means our missions are largely aligned. The university is also our home. We used to be located near The Hague Airport in Rotterdam. While we keep fond memories of this place, we are thrilled with our current workplace. This move brought us closer to students, TU Delft, and the aviation industry.”

AeroDelft collaborates on a more strategic level as well and frequently consult them for advice. The TU Delft have great insight because they are also—independent—strongly involved in the decarbonisation of aviation. TU Delft is involved with companies in the Flying Vision conglomerate. KLM Royal Dutch Airlines, Royal Schiphol Group, Airbus, Royal NLR, and TU Delft are all committing to decarbonising aviation, and the university is keen to also include AeroDelft.

“We are the leading hydrogen aircraft demonstrator at the university. Therefore, TU Delft always makes sure to include us when big delegations or events happen around the faculty of aerospace engineering because we are a perfect example of what students from the university can achieve. While we remain separate, we have benefited a lot from each other.”

What is Project Phoenix trying to achieve?
“The main goal is to prove and promote liquid hydrogen as an alternative to conventional fuels in aviation,” Ullah says. “Therefore, we built two aircraft, the Phoenix Prototype, Phoenix PT, a smaller aircraft, and the Phoenix Full-Scale, Phoenix FS. We performed the first flight trial of the prototype this June 2022. The prototype is our first aircraft to fly, since we started working on it in 2019. It’s an unmanned glider aircraft.”

The prototype is a 1:3 scale model, powered by a 1,500-watt fuel cell coupled with a battery pack for take-off power and safety, and has the ability to fly for seven hours with just one kg of liquid hydrogen. Ullah assured us it was constructive to work on a smaller scale first to explore the possibilities of hydrogen in aviation and ensure its safety. In 2020, they were able to start on the full-scale aircraft and currently, they are doing both at the same time.

As the name implies, Phoenix FS is full scale manned aircraft. While the Phoenix PT would already be the biggest aircraft ever to fly electrically with liquid hydrogen, the Phoenix FS takes it even a step further by ultimately realising the world’s first manned liquid hydrogen electric flight.

There’s a good chance other companies in the space will experiment with larger liquid hydrogen planes over time, but for now AeroDelft’s aircraft is still the largest around. But instead of competing, the team at Aerodelft invites the competition to advance the energy transition in aviation too. This is the core of their mission.

What are the next steps?
“The prototype first flew electrically. In the coming months, we aim to fly on gaseous hydrogen and then liquid hydrogen,” Ullah tells us. “The Phoenix FS is tentatively planning to fly on gaseous hydrogen sometime in 2024 and liquid hydrogen in 2025. But as we are working on something novel, there might be many challenges we cannot foresee at this stage. We are simultaneously developing and integrating what we learn from the prototype into the full-scale model.”

Can you share anything about your progress on Phoenix FS?
“With the prototype, we entirely built the structure ourselves and developed its custom electric powertrain. The full scale, on the other hand, is an existing Sling 4 kit aircraft. Amateur aircraft builders can essentially buy this aircraft, build it and then ultimately fly with it. However, rather than buying the complete kit, we only purchased the structure, such that we can develop and integrate all the internals ourselves to make it liquid hydrogen- electric.”

The Sling 4 usually is a four-seater aircraft, but to integrate the hydrogen components AeroDelft took two seats out, put the fuel cell and the tank in, and made an isolated hydrogen compartment out of it. They also made sure to separate hydrogen compartments from the passengers with a structure resistant to hydrogen flames. It is primordial to not let any hydrogen through.

In the past academic year they finished building the structure of the Full-Scale aircraft and integrated the electric powertrain. On top of that AeroDelft also flew their Phoenix PT for the first time. This contributed to an excellent year for them, one of the best years AeroDelft has ever seen.

Was there a specific incentive to work with hydrogen in relation to TU Delft or else?
“As a technical university, we apply everything we have,”Ullah assures us. “I can speak for the aerospace faculty at least; I know they are very keen on using hydrogen in aviation. They’re a big supporter of hydrogen in aviation, so we tend to look into it a lot. The outcomes have been encouraging. Looking at the aviation landscape, three main alternatives to kerosine are identified on the road to decarbonisation: batteries, sustainable aviation fuels, and hydrogen.”

Hydrogen has the most potential to power future longhaul flights while being fully sustainable. This is why AeroDelft is currently focusing on applying liquid hydrogen in aviation.

Are there any other projects in the pipeline following Phoenix?
“Currently no. The Phoenix project is already ambitious and time-consuming. We are trying to build two electric liquid hydrogen aircraft. But once we’ve reached our objectives, there might be a spinoff, or we might start a new project. But for the time being, Project Phoenix is our main project.”

The step towards commercialisation.
Considering AreoDelft’s mandate, they don’t need to worry about whether something is generating profit or not. As such, they remain very much innovation focused, which presents its own challenges because new students must learn everything from scratch every year. Generally, new cohorts start in September, and it’s only around November or December that AeroDelft can be considered operating at full capacity.

“But the beauty is, every year we give students the opportunity to develop expertise in hydrogen in aviation,” Ullah tells us. “A lot of these students go on to work in the sector. While we contribute directly to hydrogen in aviation by building and developing our technology, we also indirectly contribute through all our team members who accumulate technical knowledge with hydrogen in aviation. They often carry this knowledge with them throughout their entire careers and keep affecting change in the road to a future with sustainable aviation.”

If AeroDelf decided to commercialise, they would have to step away from the student team concept and move towards a start-up. With a start-up model, you would require more continuity and can’t afford to completely change management and have a new team every year.

It is primordial for AeroDelft to keep giving students the opportunity to work on projects and keep inspiring them, companies, and accelerating the hydrogen structure. Ullah believes that AeroDelft will stay a student-led team and remain a non-profit organisation. That is, unless some students commercialise a spinoff of their activities.

Your year at AeroDelft is coming to an end; what’s next for you?
“The academic year is now over. In the new academic year, I will personally be continuing my Master’s in Aerospace Engineering. I’ll be focusing on flight performance and sustainability. The new AeroDelft team is already in place. I have a successor, new team members, and engineers who will take it up where we left off. I will stay as an advisor for AeroDelft partly because it is difficult to let go entirely after a full year of involvement.”

On the bright side, it is also common practice for a member of management to remain available to ensure that the new team are advancing in line with the mission and give guidance and help the team whenever necessary.