MANILA, Philippines -- The military will hasten refurbishing one of its grounded C-130 transport aircraft to make it would operational within two weeks and fill the void left by the plane that crashed in the Davao Gulf last Monday, Defense Secretary Gilberto Teodoro Jr. said Thursday.

The crash left the Air Force with only one C-130 to transport troops, ammunition, and disaster relief supplies around the archipelago, with three others in the maintenance bay awaiting spare parts.

"It's not a question of procuring one more [C-130]. It's just bringing in service some more, and, within next week, or a week or two, one will be in service, so we have two [flying] and one more will be in the pipeline," Teodoro told reporters in Camp Aguinaldo.

Teodoro said a brand new C-130 Hercules would cost around $80 million US.

The defense chief said he wants a "thorough" investigation into Monday's crash, which happened after the plane lost contact with air traffic controllers shortly after takeoff from the Davao International Airport around 9 p.m.

The Air Force has ruled out sabotage as the cause of the crash and is looking at pilot error, material failure, or bad weather.

Teodoro said that while it was possible, the chances of sabotage were "slim."

The ill-fated aircraft was carrying two pilots and seven crewmen when it crashed. No survivors have been found though body parts and debris were recovered near the Davao City coast.