Google Search HTTP to HTTPS redirect yields 502

For me pretty much any query such as https://www.google.com/search?q=time yielded 502 for a while (both logged in and not), but seems to be fixed already.

Visiting http://google.com yields HTTP 502 error instead of redirecting to https://www.google.com.

Apart from that, http://wap.google.com lightweight search results page is also broken and yields 502.