Why airborne turret fighters are a poor answer to ground-attack drone swarms

Would a propeller aircraft with an autocannon or directed-energy turret be useful against one-way drone swarms attacking ground targets?

No, for the ground-defense role considered here; electronically steered ground systems are preferred, while the ability of radar emissions to disable drones remains an open question.

Defending ground assets gives an aircraft-mounted turret little advantage over truck-based systems in this assessment. Protecting airborne assets is treated as a more plausible concept, although the available technology is questioned. For small, lightly protected drone swarms, an electrical weapon could steer its output electronically, using an approach similar to a phased-array radar. Whether a modern radar at full power could disable unshielded drones remains an open question here. Several proposed counter-drone systems are compared with smaller radar units operating at adjusted frequencies and power levels.