Can airplane fly with only one engine?

Have you ever wondered what if one, two or three engines of the four-engine flight carrying you from New Delhi to Hyderabad  fails in mid-air? What would happen? Will the pilot keep flying the aircraft or it will land to the nearest airport ? The answer is right here in this post.

You would be amazed to know that you may have flown in a flight having one engine failed in mid-air or on the ground while take-off or landing without your knowing. Though engine failures are accompanied by huge noise or vibrations sometimes they are not very much noticeable, but it is required that the pilot gets to know about the failure very quickly.  

• Now we will discuss about the aerodynamic consequence of one engine failure in a two engine aircraft, but this concept is easily applicable to aircrafts having more than two engines.
• Before jumping on the core concept consider two of your friends holding your hand and pulling you to run with them. Now consider one of them leaves your hand you will get a sudden jerk and yawing motion towards your friend who left your hand, the same situation happens in an aircraft when the thrust from one engine goes off suddenly the aircraft gets a sudden yawing motion towards the engine which is failed.

If this unbalanced thrust is not compensated the aircraft would yaw very rapidly and will get out of control in seconds. Now here comes the skills of the pilot you all have read about rudder earlier which is a control surface used to control the yawing motion of an aircraft. These rudders are used very carefully by the pilot and they are turned in the direction of the operative engine so that they can provide a balancing action to compensate the action of unbalanced thrust produced due to the failure of one engine.

• For example from above picture consider  the left engine of two the engine aircraft fails then we would get an unbalanced moment acting on the aircraft in a counterclockwise direction as seen from the top. Then the rudder must be deployed in the direction of the operative engine so that we get a moment acting in the clockwise direction. This counterbalancing action would make the aircraft stable even on a single engine.

Some passenger planes do fly on one engine and so do many military planes that fly on one engine.

Cessna -172 ( works on one engine).

The F-16 uses 1 powerful and reliable engine for combat missions.

The Famous F-104 Starfighter.

• However many passenger planes like the Airbus A330, A320, A380 could fly on one engine due to safety. Even the trusted Boeing 777, 780, 737 could also fly on one engine for emergency either to return back to the point of origin or to the nearest airport. An airline could fly on one engine if it had no choice especially over the sea and will head to the nearest airport so as not to endanger the passengers on board.

Edit,Suggestion,corrections are most welcomed.