Presolicitation notice from the Department of Defense, Department of the Navy, for the procurement of 40 units of NSN 7R-2840-013949231-TN, a rotor turbine and other replacement parts. This item is typically used in the repair and modification of aircraft. The procurement requires engineering source approval and must be acquired from the approved source(s) due to the unique design capability and technical data rights held by the approved source(s). Interested parties must submit the necessary information for source approval. The proposed contract action is intended to be awarded to a single source, but all responsible sources may express their interest and capability to respond to the requirement.