Some person (at Cloudflare or Yuneec) forgot to renew the SSL sertificate? Actually, pretty easy to forget as one usually buys'em for a year or so - and if not renewed, they expire causing this. Since Yuneec seems to employ Cloudflare for content delivery network/optimalization and dns services, we as end users don't get to connect to Yuneec.com since Cloudflares server is supposed to redirect us based on where we are in the world... Should of course not happen, somewhat embarassing at this corporate level