[philipkglass]

Very interesting! This sounds a lot like the more recent iterations of the Airbus Zephyr: https://en.wikipedia.org/wiki/Airbus_Zephyr

I don't know how much you can share, but I'm curious about the solar and battery system.

Are you using silicon cells, multi-junction cells, or something else?

What sort of battery chemistry do you use? It seems like deep battery cycling is a must to keep weight under control, but battery degradation is probably the limiting factor for mission duration. The low temperature in the stratosphere also seems more challenging than what terrestrial vehicles deal with.

[jthomaslm]

Yes, Airbus’s project and team is very cool! What we’re doing shares similarities with Zephyr, but we’re focusing on a lower cost system, and a larger payload which will enable more use cases.

We’re using conventional silicon solar cells, rather than the GaAs cells used by Airbus. We give up some efficiency by doing this, but it keeps costs far lower - which we think is key to iterating quickly, and opening up some of the market use cases.

Similarly, we’re sticking with conventional battery chemistries (Lithium Ion). Battery energy density is by far the biggest driver for this technology - in the past decade we’ve seen huge advancements in battery tech, which is one of the reasons this technology is now possible. As you identify, cycle life is a key challenge and what will limit the aircraft’s endurance.

[simfoo]

> we’re focusing on a lower cost system, and a larger payload which will enable more use cases.

So you want to beat Airbus but also be cheaper. And do it with off-the-shelf components too, because those specialized ones are just too expensive. Not to say it's impossible but wow

[leoedin]

I think this is a bad take - large corporations like Airbus are terrible at R&D. They're simply not optimised for it. It's not very hard to move much, much quicker than a large corporation does - because the people inside the large corporation are having to contend with internal politics, legacy tools, legacy cost structures, and corporate inertia that doesn't like doing things a new way.

If you've worked in both a startup and a large corporation doing R&D, it's really obvious that startups are far, far more effective at it. If you gave $10m to a startup, vs a budget in a corporate project, you'd probably get 10x the result from the startup.

Where corporations excel is in scaling things up. Once you have a good design, you need a good manufacturing process and a solid supply chain. Startups rarely have the capital or knowledge to put that in place, while big engineering corporations will.

[kortilla]

That’s also how SpaceX disrupted the launch industry. Rapid iteration of cheap shit lets you learn so much more and improve the system so rapidly that competitors get left in the dust.

[Juicyy]

the main cost is labor. Airbus probably has >1k people working on that project.

[hef19898]

If so, did ever wonder why?

[hef19898]

You beat me to it! Competition is good, but so far none of the various start-ups trying to build aircraft have anything to show (boom, all eVtol companies...).

Edit: Funny, they didn't mention Airbus anywhere. But they do have the perfect founder background, Amazon Air and delivery drones. Sells good with VCs, but so far they have to get real aircraft in the air.

[nojvek]

Their YouTube demo shows a full 24hour flight.

They’re the perfect scrappy startup with fast iteration cycles.