Welcome to the forum Reaumur.
Yes - in any battle (except two exceptions I can think of - see below) you keep rolling until the attacker wins or decides to retreat.
So planes vs ground units are exactly the same.
The two exceptions that come to mind are:
1. AAA only throw once against air. But the battle goes on until the attacker wins or retreats, so it is not really an exception.
2. Subs can submerge if no enemy destroyer present, which may leave the attacker or defender with no-one to fight. Again it is not really an exception as the side with surface warships or air in the SZ that the submerged subs are in has won that battle.
Lastly, unsupported air against ground troops is risky. A lucky hit from those ground troops kills a high cost unit. Generally both attack and defence are best undertaken with cannon fodder (infantry!) alongside the high value units, if possible. Two defending infantry will on average beat 1 fighter or 1 bomber, but those planes cost a lot more than the two infantry. Of course the greater the air power in the battle (or the lower the ground unit power) the less the risk.