Drop tanks are not designed to be used as weapons, but they can potentially be used as improvised weapons in certain situations.
For example, in a desperate situation where an aircraft is being pursued by an enemy fighter and has run out of missiles or ammunition, a pilot may choose to jettison drop tanks as drop tank reduce speed and manuverability. So it is used mostly for long-range reconnaissance or strike mission and unlikely during dog fight or interception missions.
However, using a drop tank as a weapon is not a recommended or standard tactic, as it can be difficult to accurately aim and control the trajectory of the tank.
Additionally, dropping a tank can also pose a risk to civilian populations or friendly forces on the ground if it is not done carefully and in a controlled manner.
Overall, while drop tanks can potentially be used as a weapon in certain situations, they are primarily designed for their intended purpose of extending the range and endurance of military aircraft.
As a matter of fact, American pilots, they used drop tanks as bombs during World War-II sorties.