The ornamental design for a tiltrotoraircrafttailsection, as shown and described.
FIG. 1 is a right front perspective view of a tiltrotor aircraft tail section showing our new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a right side elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The tiltrotor aircraft depicted by broken lines in the drawings has been shown for the purpose of illustrating environment that forms no part of the claimed design.