The Defense Department has been flying high-tech surveillance planes to assist in the effort. The spending also includes operating costs for ships that have assisted in the search, which has stretched across the South China Sea and into the Indian Ocean.
A Navy P-8 Poseidon plane has been searching the Indian Ocean region where satellite imagery showed objects that may be from the plane. A P-3 Orion didn't fly Friday but is expected to rejoin the search Saturday.
A Pentagon spokesman says $4 million has been budgeted, and that amount could last into early April depending on the number of flying hours and whether other equipment is needed.