How much of an aviation geek are you? Can you tell the difference between most commercial plane models? Can you descipher the Airbuses, Boeings, Canadairs and Embraers? Today I'll take you through some of the visual differences between the most widely produced aircraft ever - the Boeing 737.

We'll start with the models currently in production, also known as the Next-Gen line. The easiest way to identify 737 fleet type differences is by looking at the doors.


First, the 737-700 (also known as the 73G). The 737-700 line was launched in 1993 with an order of 63 planes by Southwest Airlines. The first 73G was delivered in December of 1998. The 73G by has large exit doors forward and aft, and one emergency exit over the wing.

WestJet 737-700 by BriYYZ on Flickr

Next, we look at the 737-800, also called the 73H. Besides being longer, the 73H has two emergency exits over the wings. Germany's Hapag-Lloyd (now called TUIfly) was the launch customer for the 737-800 series.

Southwest Airlines 737-800 by the author, Paul Thompson

Now let's check out the latest and longest 737 model currently produced, the -900ER (also called the 739ER. The notable visual difference besides its length is the addition of an extra full size exit door between the wing and the aft exit. Lion Air, of Indonesia, was the launch airline for the -9ER, and received their first aircraft in April of 2007.

Turkish Airlines 737-900ER image from Boeing Media

Extra credit time! The 737-200 model is no longer in production, but are still flying around. It was first flown in 1967, but has been out of production since 1985. These can still be found in places like Africa, South America and Russia, where start-up airlines have bought these after being retired from service by other airlines. The 737-2o0 is distinguishable for its long, cigar-shaped JT8-D engines made by Pratt & Whitney.

SAT Airlines 737-200 by merlion86 on Flickr

Other 737 models still operating include the -300, -400, -500, also known as the "Classic" 737 line. The -300 has the same single over-wing exit as the -700. The -400 has the double over-wing emergency exits like the -800. The -500 has one over-wing exit but it's shortened like the -200. The 737 Classics each operate with slightly different variations of the CFM-56-3 engine. If you look closely, the engine cowling on this engine is flattened at the bottom, wherethe CFM-56-7 nacelle of the -700, -800 and -900 is more circular.


Clear as mud? Great! Now get out to your nearest airport and start identifying these birds!

State & historical info from

Top image - the Boeing 737-8MAX from Boeing Media. All images acquired from Flickr are licensed for commercial use.