Most bombers can be evade some attacks
with some maneuvers. Ok, a loop is not
a part of that.
A few bombers original used as dive
bombers. The Ju88 is a example for that.
Only the bomber tactic in WW2 with mass
attacks or night bomber single strikes
doesn't allow the dive attack. It is the
defender who send out patrols to detect
buffs on their approch.