Gundam: Zeonic Front

Federation Shield For Austin's Zaku 1:
After you complete the game once, play practice mission 1 with Austin's Zaku 1. Successfully complete it and you should have a heavy Fed shield like the Gundam's, and a few new supplies.

Char Aznable:
Get an "S" rank in Simulation Program 1.

Garma Zabi:
Get an "S" rank in Simulation Program 2.

Sayla:
Get three "C" ranks or below on the Federation missions to unlock Sayla.

Additional Missions:
Successfully complete the game to unlock another set of missions