Continuing poor weather conditions prevented further missions for another week, during which time the group continued flight training in combat formations. The 456th employed the six-combat box tactical formation favored by the Fifteenth Air Force to maximize defense against intercepting Luftwaffe fighters (for a detailed description see six-box formation). When the weather cleared on 17 February, the 456th repeated its earlier mission to bomb the command post at Grottaferrata. Although judging the results of bombing as successful, the 456th was engaged by nine fighters and severe flak, suffering its first combat losses as two bombers were shot down.