If there is any single aircraft that has undergone a significant evolution, it is the Boeing 737. From humble beginnings as the 737-100 to today's Boeing 737 MAX, how has the airframe changed?

Boeing737 1967
The Boeing 737-100 first flew in 1967. Photo: Boeing Company via Wikimedia

Understanding the changes

When the Boeing came up with the original 737 design, it was for airlines that needed a smaller regional aircraft like the 727 for short and thin routes. As it developed the model over the years, the plane became increasingly popular, and Boeing incorporated more flexibility into the design.

In the end, with better technology and improved cabins, the plane became a sought after platform for nearly every airline. Today it is hard to find an airline that has not considered the Boeing 737 or its Airbus counterpart, the A320, for operations.

But these updates were only possible with better technology and designs. While comparing the 737-100 to the 737 MAX highlights the many improvements. We do need to keep in mind that these were only possible with the hind-sight over earlier models and improved development over decades of research.

Let's begin!

Boeing 737 MAX grounded Getty Images
India and China are two major markets that are yet to reapprove the MAX for use in their respective airspaces. Photo: Getty Images

Passengers

The original Boeing 737-100 is very small, at 100 seats on board in a single class with 34 inches of legroom (very roomy compared to today). Some airlines had two classes, with 85 seats, featuring twelve in first class and 73 in the economy cabin.

Compare this to the Boeing 737 MAX range:

  • 737 MAX 7 has 138 – 153 seats in a two-class configuration. Or 172 in a single class.
  • 737 MAX 8 has 162-178 in two classes, or up to 210 in a single configuration (Ryanair is designing a new version that has 200 seats called the 737 MAX 8200).
  • 737 MAX 9 has 178-193 seats with 220 in the maximum configuration.
  • And the biggest 737 MAX 10, has 188 to 204 seats with 230 if all economy.

As you can see, Boeing recognized that airlines need as many seats as possible to make as much money as possible, and thus 100 seats on a 737 will not going to cut it. The new version fixed this problem, and now airlines have effectively double the revenue from the same plane.

Range

New engine technology has also lead to a range of improvements with the design. Bigger and better engines have pushed the envelope for what is possible.

The original Boeing 737-100, with its two 62.3kN (14,000lb) Pratt & Whitney JT8D-7 turbofans, could fly a range of 1,540 nautical miles (2,850 km). Perfect for its original mission of short routes. It is worth pointing out that the next version of the 737-200 doubled this range to 2,600 nautical miles only a few years later. 

Lufthansa 737
The Boeing 737-100 flew only a third of the distance of today's aircraft. Photo: Lars Söderström via Wikimedia Commons 

The new being 737 MAX series is a different beast with its twin LEAP-1B from CFM International engines.

  • Boeing 737 MAX 7 has a range of 3,850 nautical miles (7,130 km).
  • Boeing 737 MAX 8 has a range of 3,550 nautical miles (6,570 km).
  • Boeing 737 MAX 9 has a range of 3,550 nautical miles (6,570 km) with an extra fuel tank.
  • Boeing 737 MAX 10 has a range of 3,300 nautical miles (6,110 km) with an extra fuel tank.

Better and more fuel-efficient engines can significantly push the range of the aircraft like the 737. If today we stuck a 737-100 fuselage with the new engines it is likely it could fly as far as 3,800 to 4,000 nautical miles.

In the end, the Boeing 737 series changed with the times and matched the new standard, upgrading seats and performance to meet its airline customer goals.

What do you think? Let us know in the comments.