Asynchronous airfoil pitch adjustment for aircraft propulsion system

An assembly for an aircraft propulsion system, comprising:

• a plurality of airfoils arranged circumferentially around a centerline axis in an array, each of the plurality of airfoils projecting radially outward from a respective airfoil base to a respective airfoil tip, the plurality of airfoils including a first airfoil, a second airfoil and a third airfoil, and the second airfoil arranged circumferentially between and next to the first airfoil and the third airfoil within the array;
• and
• an actuation system configured to pivot the first airfoil about a first airfoil pivot axis from a first airfoil first pitch position, through a first airfoil first intermediate pitch position, to a first airfoil second pitch position;
• the actuation system configured to pivot the second airfoil about a second airfoil pivot axis from a second airfoil first pitch position, through a second airfoil first intermediate pitch position, to a second airfoil second pitch position;
• the actuation system configured to pivot the third airfoil about a third airfoil pivot axis from a third airfoil first pitch position, through a third airfoil first intermediate pitch position, to a third airfoil second pitch position, wherein the first airfoil at the first airfoil first intermediate pitch position, the second airfoil at the second airfoil first intermediate pitch position and the third airfoil at the third airfoil first intermediate pitch position have a common first intermediate pitch angle;
• and
• the actuation system configured to asynchronously schedule (a) pivoting the first airfoil through the first airfoil first intermediate pitch position towards the first airfoil second pitch position with (b) pivoting the second airfoil through the second airfoil first intermediate pitch position towards the second airfoil second pitch position and (c) pivoting the third airfoil through the third airfoil first intermediate pitch position towards the third airfoil second pitch position such that (i) the first airfoil pivots through the first airfoil first intermediate pitch position before the second airfoil pivots through the second airfoil first intermediate pitch position and (ii) the second airfoil pivots through the second airfoil first intermediate pitch position before the third airfoil pivots through the third airfoil first intermediate pitch position;
• wherein a chord line of the first airfoil is at least within one degree of parallel with the centerline axis in the first airfoil first intermediate pitch position, a chord line of the second airfoil is at least within one degree of parallel with the centerline axis in the second airfoil first intermediate pitch position, and a chord line of the third airfoil is at least within one degree of parallel with the centerline axis in the third airfoil first intermediate pitch position.

An assembly for an aircraft propulsion system, comprising:

• a plurality of airfoils arranged circumferentially around a centerline axis in an array, each of the plurality of airfoils projecting radially outward from a respective airfoil base to a respective airfoil tip, the plurality of airfoils including a first airfoil, a second airfoil and a third airfoil, and the second airfoil arranged circumferentially between and next to the first airfoil and the third airfoil within the array;
• and
• an actuation system configured to pivot the first airfoil about a first airfoil pivot axis from a first airfoil first pitch position, through a first airfoil first intermediate pitch position, to a first airfoil second pitch position;
• the actuation system configured to pivot the second airfoil about a second airfoil pivot axis from a second airfoil first pitch position, through a second airfoil first intermediate pitch position, to a second airfoil second pitch position;
• the actuation system configured to pivot the third airfoil about a third airfoil pivot axis from a third airfoil first pitch position, through a third airfoil first intermediate pitch position, to a third airfoil second pitch position, wherein the first airfoil at the first airfoil first intermediate pitch position, the second airfoil at the second airfoil first intermediate pitch position and the third airfoil at the third airfoil first intermediate pitch position have a common first intermediate pitch angle;
• and
• the actuation system configured to asynchronously schedule (a) pivoting the first airfoil through the first airfoil first intermediate pitch position towards the first airfoil second pitch position with (b) pivoting the second airfoil through the second airfoil first intermediate pitch position towards the second airfoil second pitch position and (c) pivoting the third airfoil through the third airfoil first intermediate pitch position towards the third airfoil second pitch position such that (i) the first airfoil pivots through the first airfoil first intermediate pitch position before the second airfoil pivots through the second airfoil first intermediate pitch position and before the third airfoil pivots through the third airfoil first intermediate pitch position and (ii) the third airfoil pivots through the third airfoil first intermediate pitch position before the second airfoil pivots through the second airfoil first intermediate pitch position;
• wherein the first airfoil is substantially parallel with the centerline axis in the first airfoil first intermediate pitch position, the second airfoil is substantially parallel with the centerline axis in the second airfoil first intermediate pitch position, and the third airfoil is substantially parallel with the centerline axis in the third airfoil first intermediate pitch position.