no rivets - sounds like it's bonded...posh glueing to us plebs...
- and by the size you describe covering a small puncture hole possibly - you dont say where it is but I would guess if you walked over and looked at it closely to see the numbers at or below eye level which is likely place for a bash by ground equipment
never seen one with date and number however with a recent AD requiring an inspection plan to be incorporated for all repairs and structural mods this could be to track the repair for ongoing inspection purposes - good idea actually - better than just referring to a position plan and would allow you to track replacement of the patch etc.
An ex Delta 727 will have posh patches and doublers - more than likely reskinned rather than patched, particularly if it's an old one as at 20 years and/or again at 60,000 cycles you reskin much of the belly in accordance with Aging Aircraft Mod. Program - you wanna see a less posh one with all the doublers and triplers all over the door frames, the roof, the chine line (eye level below windows) and above the window line...have to say it must scare the cra!p out of the pax
