The Department of Defense announced Wednesday that it awarded United Technologies (NYSE:UTX) subsidiaries a combined $36.8 million in three separate contracts.

UTC subsidiary Sikorsky Aerospace Maintenance won the largest award -- a $15.9-million modification to a previously awarded firm-fixed-price contract to perform depot-level maintenance work on aircraft operated by adversary squadrons -- the second such contract it has won so far this month. Adversary squadrons are comprised of U.S. pilots flying -- importantly -- either foreign-built planes (such as Russian MiGs), or older U.S. planes no longer in active service, flown in a style similar to those flown by foreign air forces. The unusual "air forces" involved in this training require specialized knowledge in how to maintain their planes. Wednesday's award extends Sikorsky's contract to maintain these planes through December 2013.

Sister company Sikorsky Aircraft Corp. won a separate $10.1 million award under a previously signed basic ordering agreement to perform engineering work necessary to convert a single UH-3H helicopter into a UH-3D Trainer Aircraft. This work should be completed by October 2014.

Finally, UTC's Pratt and Whitney subsidiary was awarded a $10.8 million firm-fixed-price, sole-source contract to supply aircraft engine compressors and spare parts to the Air Force. Completion date: December 30, 2016.

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