All nutrients are taken in through the center "tank" made by a rosette of leaves.

And the mass in the center tank acted as ballast.

Wing tanks are filled first and the center tank only if needed.

Investigators have found two fuel pumps from the center tank, but described them as "unremarkable."

Trystin directed three more rockets into the dirt in front of the center tank.

The aircraft, carrying 22 persons, had been modified for the flight, including the addition of five center tanks.

One other fuel rod and two pumps from the center tank had previously been found, but held no clues.

Two men had passed around that center tank, but one of them was coming back.

For the flight to Paris, the jet had less than 100 gallons in its center tank.

Still on the "most wanted list," according to a person involved in the search, is the last missing fuel pump from the center tank.