Partially shrouded aircraft propulsion system

An assembly for an aircraft, comprising:

• a first propulsor rotor;
• a powerplant configured to drive rotation of the first propulsor rotor about an axis;
• a propulsion system housing including an inner structure and an outer structure with a bypass flowpath radially between the inner structure and the outer structure, the bypass flowpath downstream of the first propulsor rotor and extending axially along the inner structure and the outer structure within the propulsion system housing, the inner structure extending axially along and circumferentially around the powerplant, the outer structure extending axially along and partially circumferentially about the first propulsor rotor to cover an outer periphery of a first circumferential sector of the first propulsor rotor, wherein a remaining second circumferential sector of the first propulsor rotor is open to an environment outside of the propulsion system housing;
• a plurality of guide vanes arranged circumferentially about the axis, each of the plurality of guide vanes extending radially across the bypass flowpath and coupling the inner structure to the outer structure;
• and
• a lobed mixer configured to mix bypass air exhausted from the bypass flowpath with combustion products exhausted from a turbine engine core, the powerplant comprising the turbine engine core;
• the lobed mixer configured with a plurality of mixer lobes, and each of the plurality of mixer lobes circumferentially aligned with a respective one of the plurality of guide vanes.

An assembly for an aircraft, comprising:

• a first propulsor rotor;
• a powerplant configured to drive rotation of the first propulsor rotor about an axis;
• and
• a propulsion system housing including an inner structure, an outer structure and a plurality of guide vanes with a bypass flowpath radially between the inner structure and the outer structure, the bypass flowpath downstream of the first propulsor rotor and extending axially along the inner structure and the outer structure within the propulsion system housing, the inner structure circumscribing the powerplant, the outer structure extending circumferentially about the first propulsor rotor and the inner structure between opposing circumferential sides of the outer structure, each of the opposing circumferential sides of the outer structure exposed to an environment outside of the propulsion system housing, and each of the plurality of guide vanes extending radially across the bypass flowpath from the inner structure to the outer structure;
• wherein the plurality of guide vanes includes a first guide vane, a second guide vane and a third guide vane disposed circumferentially between and next to the first guide vane and the second guide vane, the first guide vane is circumferentially spaced from the third guide vane by a first circumferential distance, and the second guide vane is circumferentially spaced from the third guide vane by a second circumferential distance that is different than the first circumferential distance.