Twin Hawk repair log

Got on the bench some days ago this Twin Hawk PCB (another board coming from Portugal)

Board booted up and game was playable but with bad graphics :

All the GFX data are stored in four 4Mbit MASK ROMs:

I dumped them in my programmer and the ones @3K and 3J resulted empty :

As proof of this I loaded the dumps into MAME and I was abble to reproduce exactly the same issue :

I replaced the two faulty MASK ROMs with 27c400 EPROM devices

This fixed graphics and board completely.