The invention relates to a propulsion device comprising a platform, a thrust unit, support means arranged to hold and support the thrust unit, integrally cooperating with the platform via one or more suitable mechanical connections, projecting means, integrally cooperating via suitable mechanical connections with the platform, a central foot, passing through the centre of inertia of the propulsion device and integrally cooperating via a suitable mechanical connection at its proximal end with the platform. In order to enable a landing of said propulsion device on receiving surfaces having relatively small dimensions with respect to the propulsion device and/or moving surfaces, the projecting means and the central foot are mutually arranged so that the central foot can provide the first contact between the device and a surface receiving the device.

The gas turbine engine for an aircraft includes at least a low pressure spool with a low pressure turbine shaft operatively connected to at least one turbine, the low pressure turbine shaft rotatable about an engine axis, and a low pressure compressor operatively connected to a low pressure compressor shaft that is independently rotatable relative to the low pressure turbine shaft. A differential gearbox has an input operatively connected to the low pressure turbine shaft, a first output and a second output, the first output of the differential gearbox operatively connected to the low pressure compressor shaft and the second output of the differential gearbox operatively connected to an output shaft of the gas turbine engine. The differential gearbox permits the output shaft, the low pressure compressor shaft and the low pressure turbine shaft to rotate at different speeds.

A vehicle propulsion system comprises at least two motors. Combustion occurs upstream of a first motor, and a second motor is downstream of said first motor. The first motor is a turbine that drives a primary propulsion element to effect propulsion and a compressor to effect compression. The second motor is an expansion device whose incoming gases arrive from said first motor. The first motor and the second motor intercommunicate energy via electrical, electromagnetic, and/or mechanical means. Pressurized gases that result from said compression, combustion, or both are rendered or wastegated for auxiliary usage such as aerial thrust, vertical takeoff and/or vertical landing, near-vertical takeoff and/or near-vertical landing, pneumatic storage for hybrid drive, pneumatic lift and/or drive for towing and/or raising another vehicle, aerial vehicle steering, aerial vehicle pitch stabilization or manipulation, aerial vehicle roll stabilization or manipulation, and/or aerial vehicle yaw stabilization or manipulation.

The gas turbine engine for an aircraft includes at least a low pressure spool with a low pressure turbine shaft operatively connected to at least one turbine, the low pressure turbine shaft rotatable about an engine axis, and a low pressure compressor operatively connected to a low pressure compressor shaft that is independently rotatable relative to the low pressure turbine shaft. A differential gearbox has an input operatively connected to the low pressure turbine shaft, a first output and a second output, the first output of the differential gearbox operatively connected to the low pressure compressor shaft and the second output of the differential gearbox operatively connected to an output shaft of the gas turbine engine. The differential gearbox permits the output shaft, the low pressure compressor shaft and the low pressure turbine shaft to rotate at different speeds.

The invention relates to a helicopter including a structural framework, at least one main rotor for lift and propulsion integral with said structural framework and a drive train for driving said main rotor including a power transmission gearbox and at least one main engine, wherein it further includes a plurality of extra booster power units fixed to said structural framework and configured so as to be able to supply extra lift of the helicopter in case of failure of the helicopter's drive train.

The invention relates to a helicopter including a structural framework, at least one main rotor for lift and propulsion integral with said structural framework and a drive train for driving said main rotor including a power transmission gearbox and at least one main engine, wherein it further includes a plurality of extra booster power units fixed to said structural framework and configured so as to be able to supply extra lift of the helicopter in case of failure of the helicopter's drive train.