Whereas the USN P-8 contract is for additional aircraft to enlarge an existing fleet (12 in service as of December last year with 6 of those on deployment to Japan, and brings the total of current orders to 53).
The USN contracts support separately from purchases.
Note that this is NOT a new contract, but is actually the USN exercising an option (for more aircraft) in a previously-awarded contract.
Boeing Awarded $2.07 Bln Contract By U.S. Navy For P-8 Spy Planes
2/26/2014 4:09 AM ET
Boeing co. has been awarded a $2.07 billion modification to a previously awarded firm-fixed-price contract to exercise the options for the procurement of 16 P-8A Multi-mission Maritime Aircraft full rate production Lot I aircraft and 16 Ancillary Mission Equipment kits for the U.S. Navy, the U.S Department of Defense said. The order is expected to be completed in April 2017.
The deal reportedly increases the Navy's order to 53 jets as it exercised options as part of a broader agreement that would see the service take up to 117 of the aircraft, a heavily-modified version of its 737-800 passenger plane.