Propulsion unit for an aircraft, connected to the fuselage of said aircraft

An aircraft propulsion unit comprising:

• a turbojet engine;
• a lateral mast directly connected to a fuselage of the aircraft, said lateral mast being positioned at about 90° or at about 270° relative to a substantially vertical midplane of the propulsion unit when the propulsion unit is connected to the fuselage of the aircraft;
• and
• a nacelle mounted on the lateral mast and surrounding the turbojet engine, the nacelle comprising:
• an upstream section comprising an air inlet of the nacelle;
• a downstream section configured to accommodate a thrust reverser device;
• and
• a middle section disposed downstream of the upstream section and upstream of the downstream section, the middle section comprising two fan half-cowls surrounding a fan casing of the turbojet engine,
• wherein when the two fan half-cowls are in a closed position the middle section defines an aerodynamic continuity between said upstream section and said downstream section of the nacelle, the two fan half-cowls including at least one maintenance half-cowl positioned under a substantially horizontal midplane of the nacelle and movable between the closed position and an open position enabling access to the turbojet engine for maintenance operations on the turbojet engine, and
• wherein the nacelle includes at least one standby lock to hold the at least one maintenance half-cowl in an intermediate position between the closed position and the open position, and
• a locking device for locking the two fan half-cowls in the closed position, the locking device comprising:
• at least one tension lock to fasten the two fan half-cowls on the lateral mast;
• and
• at least one shear lock to fasten the two fan half-cowls on at least one of the upstream section and the downstream section of the nacelle and forming a force path for the at least one tension lock, the at least one shear lock comprising:
• a shear pin extending from one of the fan half-cowls;
• and
• a shear receptacle mounted on at least one of the upstream section and the downstream section of the nacelle, the shear receptacle comprising a shear latch cooperating with the shear pin when the two fan half-cowls are in the closed position and a ramp slidably directing the shear pin to a deployed position when the two fan half-cowls are moved to the closed position,
• wherein the at least one standby lock of the nacelle includes:
• a standby pin;
• and
• a standby latch mounted on the shear receptacle between the shear latch and the ramp and cooperating with the standby pin,
• wherein the standby pin is offset with respect to the shear pin,
• wherein the standby pin is disposed in the standby latch when the maintenance half-cowl is in the intermediate position.