I recall witnessing in DaNang airbase two F-4, wingtip to wingtip, taking off like, truly, a bat out of Hell. The noise was spectacular and the fire from their anus burned red hot. It is a scene I shall never forget.
I saw the same thing at Da Nang. A few weeks later an F-4 gave us a little help and we could feel the heat “from the ass end” as we put it.