B-29 bomb bay

[Pathfinder]

Hope someone can help sort out this question: As boring as it may sound, I've been studying the bomb-bay area of the B-29. Looking at several sources, including scale drawings, a quality scale model, and an original wartime photo I own, I have measured that the rear bomb bay doors are slightly shorter in length than those of the front bomb bay.

However, there are some written sources that state the bomb bay doors are the same size. I am sure there is a difference though. If anyone has access, check out scale drawings and you will see there is a slight difference, not much, but a difference none the less. I noticed it while looking at a photo to work on a piece of art.