The Three Valleys of Death of Aviation Startups

When I first started working on climate hardware, I thought in terms of one valley of death.

You raise early money, build a prototype, and then you face the brutal task of scaling up manufacturing. If you survive that stage, you have a shot at becoming a real business.

Talking to Dirk Singer, author of Sustainability in the Air, made me realise that aviation startups face not one but three valleys of death. That difference explains why progress in aviation feels so much slower than in energy, batteries, or transport.

The paradox of aviation emissions

Today, aviation accounts for roughly 2.5–3% of global CO₂ emissions. A small slice compared to power generation or road transport. Dirk points out that this share is set to rise to over 20% by 2050 as other sectors decarbonise faster.

The paradox in aviation is that it is relatively small in size but disproportionately hard to clean up. Physics, regulation, and industry structure all conspire to slow it down. Here is how Dirk describes these three valleys and my takeaways.

“Valley one is the product risk: does the technology even work in the real world?”

This is not like shipping an app or even launching a new battery cell. In aviation, the baseline is safety at 30,000 feet. Certification cycles run 7–10 years, and a promising lab prototype is only the beginning of a decade-long journey.

Only a handful of electric or hydrogen aircraft have flown at all, and those are small prototypes. Getting from the first flight to a certifiable aircraft is a leap few survive.

“Valley two is the commercial risk: can you secure real customers, not just pilot projects?”

An airline agreeing to a pilot (no pun intended) is not the same as signing a binding contract for a fleet of new aircraft. Airlines operate on tight margins, and their willingness to bet on unproven technology is low.

Compare this to wind or solar, where offtake contracts are well established. In aviation, offtakes are rare and often symbolic. Universal Hydrogen managed some test flights and had great press coverage. But when the time came to turn MOUs into orders, investor confidence collapsed. The company shut down last year despite raising over $100 million.

“Valley three is the scale risk: can you build and deliver reliably, under budget and at volume?”

Even if you have a working aircraft and a first customer, you still face the Everest of industrialisation. Dirk used the example of Elysian, a Dutch electric aircraft startup. Their 90-seater design could take $5–8 billion to bring to market, with realistic service entry no earlier than 2033.

That number dwarfs the capital needs of most climate hardware projects. And it explains why, outside of eVTOL, only five aviation startups worldwide have ever raised more than $100 million.

Beyond hype

Aviation is a test of patience. Investors accustomed to 5-year exits in SaaS or AI will find the timelines unbearable. And yet, if we ignore aviation, its emissions share will balloon as other sectors clean up.

Dirk’s framework of the three valleys is a reminder that hype won’t carry us through. Only staged capital, credible execution, and realistic timelines will.

And perhaps the hardest truth: success in aviation may not look like disruption from a startup, but gradual infiltration of sustainable fuels, small-scale electrification, and eventually, a reshaped industry.

Watch the full interview with Dirk Singer here: <iframe width="560" height="315" src="https://www.youtube.com/embed/xtHv0QHEZ0E?si=HCv3Jc_8Q_l1ny3D" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen></iframe>