Year-old startup Flapping Airplanes has wowed Silicon Valley with an impressive founding team and a mission to find ways to train large models with less data. On Wednesday, the company announced it had raised a $1 billion Series A round, co-led by Index and Lux, reportedly at a $6 billion valuation.

The round comes just nine months after the company launched with a $180 million seed round from GV, Sequoia, and Index. That seed round had valued the company at $1.5 billion, so its valuation just quadrupled.

Other participants in the new round included earlier backers Sequoia, GV, and Kleiner Perkins. Valor, Atreides, Kleiner Perkins, A*, and Nvidia are also investors in the company.

Flapping Airplanes was founded by Aidan Smith and brothers Asher and Ben Spector. Smith is a former founder and Thiel fellow who worked at the brain implant company Neuralink during college.…