Here's the output of tcpdump
21:29:38.028294 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
I understand that flags are for the 6 tcp control bits. So I could assume that 'F' is for fin? What does the 'D' stand for? Or does it stand for fin? It doesn't make sense this is the first packet out when pinging a domain.