Abstract: A vertical take-off and landing aerial vehicle (VTOL) includes a plurality of rotors for producing lift. For each respective rotor the VTOL has an auxiliary power source (APS) and a transformation gear set (TGS) both being associated with the respective rotor, and the VTOL further includes at least one main power source (MPS). Each TGS is configured to form an outgoing power towards its respective rotor from input powers received into the TGS from the MPS and from the APS associated with the respective rotor.