Most Popular Commercial Airliners

The largest commercial airliner in current service is the Boeing 747 shown below. This design is now over 20 years old, but there have been several changes and improvements to the original version. It appears that this type of machine is about as big as currently practical and useful. This type of machine probably represents some sort of milestone in commercial aircraft design. Larger aircraft are currently in use by the military.
The most successful commercial jet powered airliner to date is the Boeing 727. It is a medium haul aircraft capable of many landings and takeoffs during a day. It is powered by three engines mounted at the rear. This configuration has become obsolete as the advantage of two wing mounted large engines became possible as more powerful and reliable engines have evolved.
A very long range commercial airliner in current (2002) use is the Airbus 340 shown below. The difficulty with long subsonic flights is passenger comfort. Long range aircraft will fly nonstop for over 12 hours. This is quite fatiguing for both passengers and crew. Such long flights allow non stop trans Pacific flights, etc.

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