Before looking at today's fleet, let's take a step back for some historical perspective. Before the deregulation of the US aviation industry, the world jet fleet in 1977 comprised approximately 6,500 airplanes, the majority of them single aisle. Boeing and McDonnell Douglas provided 65 percent of the fleet, mainly 707s and 727s. There were roughly 290 airlines, with the top ten having more than a 50 percent fleet share. The top ten airlines were very similar: all large network carriers, the majority located in North America, providing both domestic and international service. Today, three of those top ten airlines--Eastern, TWA, and Pan Am--are no longer in service.
Today there are more than 900 airlines in operation. Boeing is still the dominant manufacturer, with 50 percent of the in-service jet fleet. The airlines with the largest fleets are a diverse mix, including low-cost carriers and cargo carriers, as well as airlines originating outside North America.
Single-aisle airplanes still comprise an overwhelming majority of the fleet, reflecting little change in share percentage, having risen to 63 percent of the fleet in 2011, compared to 62 percent in 1977. The number of single-aisle airplanes, however, has grown by 200 percent to more than 12,600 airplanes from 4,000 during the same period. The number of twin-aisle airplanes rose 600 percent to 3,700 from 518. Only the regional jet category reported a large percentage decline, down 11 percentage points, although the number of regional jets has increased by 1,100 since 1977.
At year end 2011, at least 30 percent of the installed commercial fleet was based in the United States. The second largest share belongs to China, with 9 percent. Russia, the United Kingdom, and Germany, at a combined 12 percent share, split the third largest share about evenly. Commercial airplane backlogs indicate that the geographical diversity of the order base is growing. The United States and China retain their respective top two positions as new entrants, including India, the United Arab Emirates, Malaysia, and Indonesia, gain a significant presence. Russia also has a sizable backlog of aircraft on order and will remain a large base for the commercial aviation industry.