Hacker News new | past | comments | ask | show | jobs | submit login

are you talking about ducted fans? if so I've wondered the same thing. here's a plausible answer: https://aviation.stackexchange.com/questions/36726/why-dont-....



Join us for AI Startup School this June 16-17 in San Francisco!

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: