Abstract: The control system of an aircraft including at least two communication networks and a controlled device control unit connected to one of them. The system determines control commands for the device with a DAL-A quality assurance level requirement and includes a set of at least three physical units each including at least two computers, an electrical power supply and a network interface device. The electrical power supplies, and the network interface devices, are of at least three different types, the computers are of at least two different types and include operating systems of at least two different types; the computers each have a DAL-C, DAL-D or DAL-E hardware and/or software quality assurance level and at least six of the computers are configured to independently determine control commands for the device. A DAL-A hardware and software quality assurance level selection logic unit is configured to select valid control commands used by the control unit to control the device.

Abstract: The control system of an aircraft including at least two communication networks and a controlled device control unit connected to one of them. The system determines control commands for the device with a DAL-A quality assurance level requirement and includes a set of at least three physical units each including at least two computers, an electrical power supply and a network interface device. The electrical power supplies, and the network interface devices, are of at least three different types, the computers are of at least two different types and include operating systems of at least two different types; the computers each have a DAL-C, DAL-D or DAL-E hardware and/or software quality assurance level and at least six of the computers are configured to independently determine control commands for the device. A DAL-A hardware and software quality assurance level selection logic unit is configured to select valid control commands used by the control unit to control the device.

Abstract: The present invention relates to a blade with a swept-back tip for the rotary wings of an aircraft, particularly a helicopter, said blade (1) being formed from successive elementary cross sections. According to the invention, with said blade (1) being subdivided into various zones, the chord length L and the offset Y′f of the aerodynamic center with respect to the feathering axis (OX), as well as the relative thickness of each elementary section, are optimized for flight within a moderate speed range.