A Pizza Freezer, Plumbing, and Perseverance — How Ubiq Built an Icing Wind Tunnel in their office.

"We realized we were spending a lot of money and getting too few test sessions in return"

Twice a year. That’s how often the Ubiq team could run tests at a commercial icing wind tunnel in Finland. It is expensive, time-consuming, and not nearly frequent enough to keep pace with their development goals. So in 2021, they decided to build their own.

"We realized we were spending a lot of money and getting too few test sessions in return," said Bård Stovner, Head of Autonomy. "We needed something in-house to speed up iteration and innovation."

The answer was simple in principle, if not in execution: build a small-scale icing wind tunnel that could simulate cloud conditions and allow rapid testing of components like sensors and heating systems. A place where ideas could fail fast—and improve even faster.

"We made every mistake you can make"

Mistakes, algae, and 1 cm clearance

The result is lovingly known as the mini-IWT (mini icing wind tunnel), and its origin story is one of trial and error, plumbing mistakes, and the occasional swimming-pool smell.

"We made every mistake you can make," said physicist Lars Stephan Klein, who led much of the build. "We fought algae. We rusted components with chlorine. We clogged nozzles. It was glorious," he laughed.

And then there was the cold room—a commercial pizza freezer selected specifically because it could (just barely) fit into the building’s elevator. "There was literally a one-centimeter gap," said Stovner. "We held our breath the entire time."

A humble setup, powerful results

The mini-IWT isn't scientific-grade, and it doesn’t have to be. It produces supercooled droplets and subzero airflow in a controlled 10x10 cm chamber—more than enough to test prototypes and iterate quickly.

"It’s about verifying concepts," said Klein. "You don’t need full atmospheric replication to see if something basically works. That’s what we use this for—the 90% of tests that don’t need a million-dollar setup."

Custom-made, end to end

Everything from the airflow to the heating system to the water delivery and control interface was built in-house. "We wired the pipes ourselves, figured out the heating, wrote the software," said Stovner. "And we did it on a tight budget."

Eventually, the team connected the system to a computer, allowing them to control temperatures, airspeed, humidity, and cameras with a few clicks. "It's now more automated than some commercial setups we've seen—and far more adaptable to our needs," Klein added.

What it enabled

The biggest win? Speed. Ubiq developed a new airspeed sensor in just two months, thanks to rapid prototyping and in-house testing. "The turnaround time would have been impossible with outsourced testing alone," said Stovner.

The time, energy and resources required planning a campaign, and packing and travelling to an IWT facility are immense. With the mini IWT available, much of this could go to development instead.

"It shaped how we work. We learned how to build, how to fail, and how to keep going. That mindset is everywhere at Ubiq"

A blueprint for future development

The experience will prove invaluable when Ubiq moves forward with plans to build a full-scale icing wind tunnel. But even now, the mini version has paid for itself many times over.

"This wasn’t just about testing," said Klein. "It shaped how we work. We learned how to build, how to fail, and how to keep going. That mindset is everywhere at Ubiq."

When asked what they’re most proud of, both engineers laugh. "Probably the plumbing," said Stovner. "And the fact that it actually works. That part never gets old."

Sometimes, innovation starts with a control system and a pizza freezer—and ends with a world-class aerospace team getting better, faster, and smarter at everything they do.