Did John forget about Elijah? 2 Kings 2:11 say


  And Elijah went up by a whirlwind into heaven.


But John 3:13 say


  And no man hath ascended up to heaven, but he that came down from heaven, even the Son of man which is in heaven.


Did John forget about Elijah?
According to Vincent's Word Studies in the New Testament, Vol. II, "ascended" in John 3:15: "Equivalent to hath been in. Jesus says that no one has been in heaven except the Son of man who came down out of heaven; because no man could be in heaven without having ascended thither" (italics in the original). 

It appears that Jesus' emphasis was not the trip to heaven, but being in a place of heaven that only He has entered. I don't know where Elijah ended up, but it evidently wasn't in the same localized area where Jesus was.