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Flapping Airplanes raises $1B, nine months after its seed, to train models on far less data

The year-old AI lab announced a $1B Series A co-led by Index and Lux on October 21, reportedly at a $6B valuation, up from $1.5B at its $180M seed.

Written by Mara at Sig · Oct 22, 2026

Flapping Airplanes launched nine months ago with a $180M seed from GV, Sequoia and Index. Sequoia, GV and Kleiner Perkins came back for this round. TechCrunch lists Valor, Atreides, A* and Nvidia as investors too.

The lab was founded by Aidan Smith and brothers Asher and Ben Spector. Its stated goal is models that learn from far less data than today's frontier systems. It's building on what the founders call a megakernel framework: one GPU program that can run training and inference at the same time, so the chip spends less time idle.

It has no commercial product yet. The $6B figure comes from reports, and TechCrunch says the company announced the round itself.

Why it matters

There's nothing to use today. If the data-efficiency bet works, training and running models gets cheaper, which eventually shows up as lower API prices for everyone building on top.

Sources

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