An intense spending fight over a second engine for the Joint Strike Fighter has partners General Electric and Rolls Royce and rival Pratt &

The F35 is having trouble with its high-tech helmets and structural cracks and skin repairs and tailhooks and more.

New F-35 program deputy gives a candid assessment of flaws in the most expensive weapon in Pentagon history.

Fuel line leaks and a special vulnerability to lightning are the latest troubles for the Pentagon's advanced fighter jet

UPDATE: Early flight tests show multiple problems but the program gets new funds just before sequester.

The most costly military program in history might wind up busting the Pentagon budget