Successfully complete the following tasks to unlock the corresponding Pilot and MSes.

Unlock Amuro Ray:
On Very Hard mode beat EFF campaign and load the clear data.

Unlock Char Aznable:
On Very Hard mode beat Zeon campaign and load the clear data.

Unlock Fraw Bow:
On Very Hard mode beat any campaign and load the clear data.

Unlock Kai Shiden:
On Very Hard mode beat any campaign and load the clear data.

Unlock Gundam:
Reach the rank of Warrant General.

Complete the following tasks to unlock the corresponding characters

Unlock Kampfer:
In the Zeon campaign get the rank of 'Lt. Colonel'.

Unlock RX-78-2 Gundam:
In the Federation campaign get the rank of 'Colonel'.