A 747, once airborne, can climb on 3 engines. Fully loaded, with gear down. A jet requires a lot less power to cruise than to take off. Normally they’d opera

A 747, once airborne, can climb on 3 engines. Fully loaded, with gear down. A jet requires a lot less power to cruise than to take off. Normally they’d operate at 80-90% power when cruising, but they can stay airborne with much less power. How much power it takes to stay airborne depends on many factors, such as weight, altitude, wind conditions and temperature, but 747s have been known to fly and land safely with just two engines.