Think of the net momentum balance. Some mass of air is entering the intake at lo...

		asdfadsfgfdda on Jan 30, 2019 \| parent \| context \| favorite \| on: Boeing 787 Suffers Rare Dual Engine Failure on Lan... Think of the net momentum balance. Some mass of air is entering the intake at low speed, the engine does work on the air, then the air exits the front at very high speed. The intake speed is approximately the airplane's speed (150 mph), while the exhaust speed is probably 500 mph.