Swarms of drones is an emerging field of research and technology. Multicopter drones are noisy machines, and the noise effects would increase for a swarm. It is, therefore, essential to understand what flight formation conditions would reduce noise emissions. This study concerns the noise induced by drone swarms. We developed a high-resolution computational methodology for predicting aeroacoustic footprints emitted from a swarm of multi-copter drones. We show that a V-flight formation emits less sound pressure level noise than a U-shape (or rectangular) formation. We also demonstrate that the V-shape flight formation induces reduced drag, thus saving energy. This research's impact is broad, including defence and security, public health, transportation, and surveillance, among others.