AST, Automation Source Technologies, has a line of compact “pancake” motors that are of interest to those designing electric aircraft. Their CDS Series have power outputs ranging up to 21 kW, efficiencies up to 93.2 percent, and weights of no more than 21 kg. The CDS 150, largest in the line, can be either water or air-cooled, handles inputs from 24 to 96 Volts DC, and operates at 1,000 to 6,000 rpm. High torque peaks, and a three to four times overload capacity might make this eight-pole series worthy of consideration.