DALLAS — The Boeing 737 remains the most popular aircraft in history. Since its launch in 1965, this airplane has secured more than 15,000 orders across all the variants. The most successful variant of the Boeing 737, the Next Generation, makes up more than 60% of all the delivered aircraft, earning it the title of the most common airliner in the world.

However, while not so common, there is still one country where you can find airlines today flying the 1967 Boeing 737-200 variant.

The number of 737-200s operating with Canadian registrations in 2022 is not small; a total of 19 units of the 55-year-old, fuel-inefficient airplane fly regularly for airlines within Canada.

Air Canada (AC) and WestJet (WS), which operate modern airliners like the Airbus A220 or the Boeing 787, share the domestic market with plenty of the oldest 737 aircraft flying today.

What are the reasons that encourage Canadian airlines like Air Inuit (3H), Chrono Aviation (MB), or Nolinor Aviation (N5) to still operate almost half of the total Boeing 737-200 worldwide airplanes in 2022?

The Boeing 737-200

The Boeing 737 saw its preliminary design works begin in 1964 when Boeing started looking for another short-haul aircraft to complement the recently introduced Boeing 727. The North American company was looking for a small airplane able to operate short routes with thin demand.

Because of that, Boeing needed to develop an aircraft that could be adapted to the circumstances of small airports with poorer ground services. As a result, they decided to add two engines to the aircraft, which would be mounted directly beneath and across all of the wing chords.

This enabled the 737 to operate with a very low landing gear, which allowed the ground crew to have easier access to the passenger and baggage compartments of the cabin without a complex system of ground vehicles.

The Boeing 737-100, the first variant of the product, only came with 31 units built. For context, the last -100 in commercial service was retired in 2003, the Mexican Air Force retired one in 2004. The first one built, which was operated by NASA its whole life, was preserved in 2004 and is the only 737–100 still in existence.

The -100 entered service with Lufthansa (LH) in February 1968, followed by its bigger brother, the Boeing 737-200, just two months later with United Airlines (UA). These two variants make up the Boeing 737 “Original” family.

The Boeing 737-200 proved its success by delivering 1,000 units to regional customers worldwide. The last unit entered service with Xiamen Airlines (MF) in August 1988. Since then, the “Baby Boeing” has been improved in terms of its aerodynamics, fuel efficiency, and passenger comfort.

However, Boeing always maintained almost the exact flying systems and procedures, enabling most pilots to operate all variants of the type with only one certification, reducing the costs of crew training.

The first Boeing 737-200 entered service with United Airlines in 1968. Photo: Aero Icarus, Creative Commons BY 2.0

The Bypass Ratio

The engines chosen to power the Boeing 737-200 were the Pratt & Whitney JT8D-1 turbofans, and they played a vital role in influencing the evolution of the aircraft throughout history. These engines, which can provide the airplane with a force of up to 17.400 pounds, have the specific characteristic of being built with a 0.96:1 bypass ratio.

The bypass ratio (BPR) of a turbofan engine is the proportion of the air that flows through the combustion chamber to the total air mass that enters the engine core. For example, if a specific engine has an air bypass ratio of 5:1, it means that there is 5 times more air flowing around the compressor than inside the combustion chamber.