Working on the ramp at Term. 6 yesterday between the hours of 11:30am and 12:15 I noticed coming from 13L a BA 744 about 200ft above the middle of the runnway. Now theres noway that it took off if in that about of feet so I'm thinking it had a miss approach. I never saw it come back on 13L so i'm kinda puzzled. Maybe I'm making something out of nothing but thats where you guys come in. Any of you JFK workers or spotters hear anything about it yesterday???? Come back to me with your thoughts.