If we shutdown the airplane engine, can we still land safely?

The answer is the same as the catchy slogan in Obama’s first Presidential campaign: Yes, We Can!

Regulations - and good design sense - require that airplane performance be well-defined after an engine is shut down (for whatever reason). That is how 2-engined aircraft have grown in size, range, and passenger capacity: they have demonstrated the ability to safely land the plane when an engine is shutdown, whenever in flight it may occur.

I am going to confine my discussion to two-engined aircraft, since an engine shutdown in such an aircraft sounds so scary, and since four-engined aircraft are today a very small minority of the world commercial airline fleet.

When it became clear that airlines were very keen on cutting fuel costs and were sick and tired of flying “four-engined money burners”, regulators and the two prominent aircraft manufacturers got together to evolve a st of safety standards known as ETOPS (Extended-range Twin-engine Operational Performance Standards). There are different levels of ETOPS certification, each allowing aircraft to fly on routes that are a certain amount of single-engine flying time away from the nearest suitable airport. For example, if an aircraft is certified for 180 minutes, it is permitted to fly any route not more than 180 minutes single-engine flying time to the nearest suitable airport. See the Wikipedia entry for ETOPS for more information.

Being ETOPS compliant for a particular class, say 180 minutes, also implies that the airplane will have certain technical features and back-up systems built in to safely cater for additional system failures after one engine has failed (or is shutdown).

ETOPS operational certification involves compliance with additional special engineering and flight crew procedures in addition to the normal engineering and flight procedures. Pilots and engineering staff must be qualified and trained for ETOPS. As operators sought to upgrade their existing airplanes to some level of ETOPS, they were required to carry out these technical and operational changes.

Today, all aircraft manufacturers sell aircraft which are “ETOPS ready”, and all the airline has to do is to prove to its regulator that it has the proper crew training and operational procedures in place.