Definition
The angle, measured in degrees, between the aircraft's actual flight path through the air and the horizontal plane. A descending flight path produces a negative angle; a climbing flight path produces a positive angle. On instrument approaches such as RNAV (GPS) procedures with vertical guidance, a published FPA defines the descent gradient the aircraft must follow from the final approach fix to the runway.
Plain English
The up-or-down angle of the path the airplane is actually travelling along, measured against level flight. A small negative number like −3.00° means a gentle descent.
Context Anchor
Seen in instrument procedures, vertical guidance, and aircraft displays that help manage a climb or descent path.
Why Pilots Care
It determines the actual climb or descent rate needed for obstacle clearance and stabilized approaches.
Analogy
Think of a road going up or down a hill. The flight path angle is like the steepness of that road, but for the airplane’s actual path through the air.
Intuition Check
Do not confuse flight path angle with pitch attitude. Pitch attitude is where the nose points; flight path angle is where the aircraft is actually going.
Example Sentence 1
The approach chart specified a flight path angle of −3.00°, so the crew set that value in the FMS before beginning the descent.
Example Sentence 2
A negative flight path angle of four degrees produced the required descent rate on the arrival.