Compressor blades constructed of composite materials are disclosed. Some example compressor blades may include a composite blade panel including an airfoil having a span extending radially outward with respect to an axis of rotation and/or a blade attachment feature radially inward from the airfoil with respect to the axis of rotation. The blade attachment feature may be circumferentially oriented with respect to the axis of rotation. The blade attachment feature may be arranged to releasably engage a generally circumferentially oriented spool attachment feature. The spool attachment feature may be generally shaped as a circumferential dovetail slot configured to slidably receive the blade attachment feature therein.