An apparatus and method for locking a composite component such as blade or vane of a turbine engine is disclosed herein. The disclosed lock can also be used generally to fix the position of composite structures. The lock includes a first locking member including a first structure operable to at least partially fix the first locking member along an axis of a slot for receiving a blade or a vane. The lock also includes a second locking member including a second structure operable to engage the blade or vane. The first and second locking members are slidably engaged with one another along mating ramped surfaces.