Definition
A required crewmember on certain large or complex aircraft whose duties are to monitor and manage the aircraft's engines, fuel, electrical, hydraulic, pressurization, and other onboard systems during flight, allowing the pilots to concentrate on flying and navigation. The position requires a separate FAA Flight Engineer certificate, with ratings issued by aircraft type (reciprocating, turbopropeller, or turbojet powered).
Plain English
A specially licensed crewmember who sits behind the pilots on some larger aircraft and runs the airplane's systems -- engines, fuel, electrics, hydraulics -- while the pilots fly.
Context Anchor
Seen in crew qualification rules, aircraft operating manuals, and discussions of larger aircraft that use a three-person flight crew.
Derivation
The word 'engineer' comes from the Latin 'ingeniator,' meaning one who designs or operates engines and machines. A flight engineer is, literally, the person responsible for the engines and mechanical systems while in flight -- a role carried over from ships, where the engineer worked below decks managing the machinery while the captain navigated.
Why Pilots Care
On aircraft that still require the position, the flight engineer ensures critical systems stay within limits, directly affecting safety and flight continuation decisions.
Intuition Check
Do not assume a flight engineer is an aircraft designer. In this context, the flight engineer is an operating crewmember on the aircraft.
Example Sentence 1
On the Boeing 727, the flight engineer sits at a side-facing panel and manages the fuel, electrical, and pressurization systems throughout the flight.
Example Sentence 2
Before engine start, the flight engineer verified all hydraulic pressures and electrical loads on the panel.