User blog comment:Hdutt2/Hdutt2's BioShock: Downfall - Novel: Breaking and Entering - Equator Part 1/@comment-6024608-20131008022857

" I swiped the card across the lining of the scanner before it turned green "

no world tech like this existed in WW2-era you may want to elaborate the characters confusion about the device and what he has to do to make this futuristic tech work for his entry.

Also  'silo'  doesnt make sense in your usage  - its either a hole in the ground (like a missile silo) or a upright industrial building used to store materials (like a grain silo)