Virtuali, are you saying that B747s cannot cross the two pair of bridges to reach the NW part of KJFK? These bridges appear to be the same size.
I haven't said anything specifically related to *that* bridge. I've simply said, in general, that it's not possible to make mistakes in dimensions bigger than 15 cm, comparing to real life.
The problem of the 747 engines might be a different issue, like positioning and/or dimensioning of the red/white shoulder barriers, but the taxiway widht is correct, which was the original question.