I didn't screen these ones, but my thoughts:
Bad quality, bad centred as per the screener who rejected.
Bad quality: overall the image looks like it needs minor adjustments in areas. You'll generally get this rejection:
a) if original image has reduced quality
b) if problem area of image is too hard to pinpoint or too numerous to list
You appear to have used a smart blur to reduce grain, but if so, it has actually damaged the shot, reducing detail. (Or it a least looks like that)
The fuselage generally has to be centred. This isn't. Your fuselage is simply too low. Nice easy fix!
Please note, while bad centred may seem pedantic in this example, it only become so when the aircraft your shooting becomes more common (i.e. currently flying, over 10 shots, high chance of additional photos).
See my reply 38 in:
Bad angle as per rejection, but also I would have added bad soft.
This is far too soft! Anything this soft is a rejection in my books unless rare, old or accident. Once again, an easy fix.
Also once again, you've used a smart blur or filter in such a way where the detail is smoothed too much. To counteract this you appear to have over sharpened (which doesn't improve the soft rejection I would have given you) and in-turn created jagged edges (see ANA titles near door).
For this, I would have added bad jagged (quite rare to also be mixed with bad soft).
The above said, it's not your camera that's creating these rejections. You don't need an upgrade to a D100. You shots are as good or better than most of the D100 rejections I am seeing lately.
Your rejections can be helped by changing your editing technique. Your photography technique and scanning technique appear to be above normal.
Respected users.... If my replies are useful, then by all means...