Just Two Ever Built: Boeing’s Rare 737-700ER

Over the years, the Boeing 737 series has proven to be a popular family of narrowbody twinjets, with almost 12,000 examples across all variants having rolled off the production line since the late 1960s. Several variants have sold thousands of units in their own right, but if we dig a bit deeper, we can soon uncover subvariants that were produced in limited numbers for specific airlines.