Four small coreless motors are used for propulsion, driven by tiny MOSFETs, and the whole assembly is run via a teeny 220 mAh lithium-polymer battery. Oh, and there’s an FPV camera so you can ...

The total current drawn is 8A peak. The 48A MOSFET is mounted on a small heatsink for reliability but it doesn’t even get warm. The trouble here is if the Arduino crashes, the 555 output stays high.