Shuaibkazi,

The light standards are less than 6 m high (the plane passed above them).

Ferrous oxide is rust (maybe why the renovation/rebuilding was taking place).

The plane hit the side that was along a resonably flat, reasonably open area (the Pentagon is not 80 some stories in the air so the plane had to approach reasonably close to the ground).

I was there shortly thereafter and it was not a small hole (any fool can edit photos for a website).