In January 2019, on a domestic route in Iran operated by Iran Aseman Airlines, the Boeing 727 made its last commercial flight. After nearly 55 years of service, the era of the distinctively designed tri-jet had come to an end. Once the most popular aircraft in the world, how come it fell out of favor with airlines?
Boeing launched the 727 project in December 1960 with 40 orders each from United and Eastern Air Lines. The first one rolled out of the company’s Renton factory in Washington state in November 1962. It then took its maiden flight a few months later in February 1963. It first entered service with Eastern Air almost precisely one year later with a flight between Miami, Washington DC, and Philadelphia.
Greatly exceeded expectations
Boeing’s initial production run was for 250 aircraft, which was 50 more than they had calculated they needed to sell to break even. However, the larger passenger version proved incredibly popular. Boeing ended up selling 1,832 of them. Production ended in 1984, with a 727 freighter model being delivered to Federal Express.
The 727 was one of the first successful short and mid-range passenger jet. Its arrival was essential to shaping commercial aviation into what we know it to be today. So how come airlines moved on to other models?
Engines, engines, engines
First, there is the obvious consideration of fuel-consumption. With the rise of the single-aisle twin-jet, the tri-jet has become as uneconomic an option as the quad-jet when compared to its more modern long-haul two-engined competitors. And while fuel prices may fluctuate, an extra engine also adds a ton of maintenance costs, not to mention the sustainability aspects in an ever-increasingly environmentally conscious market.
The location of the engines also contributed to maintenance expenses. Engines hanging from the wings or located low on the body are much easier to access and maintain. And should one need to be entirely replaced, it is much easier to lift it off, than to have to dig it out of the fuselage.
The 727, like other early four and three-engined jets, also required a flight engineer to come along in the cockpit on each flight. A flight engineer (“air engineer” in the Royal Air Force) monitors the aircraft’s systems while in flight. On early multi-engine commercial planes, they were responsible for engine power during take-off, climb, cruise, go-around, or at specific requests from the pilot.
A three-person flight-deck allows the captain to hand over the flying of the plane to the first officer, and evaluate problems together with the flight engineer in case of any trouble or an emergency. However, having this extra individual on board most certainly contributed to high operating costs for the 727, compared with later models.
Furthermore, the entire rear fuselage of the 727 was designed around the Pratt & Whitney JT8D engines. This type of low bypass engine has nearly disappeared due to its high noise levels. While the early versions of the 737 (-100 and -200) also featured them, the fuselage was much easier to redesign for more modern and fuel-saving high bypass engines.
Outshone by its stablemate
The 727’s stablemate, the 737, eventually came to fill the functions of its predecessor with much less hassle and no extra crewmate on board. The 737, which took its first flight only four years after the 727, was to become the most delivered aircraft to date. Although, the Airbus A320 has since surpassed it in orders.
In the first few years of coexisting on the market, the 727 and the 737 still occupied a slightly different segment. The 727 could fit more passengers than the earlier models of its twinjet competition in most configurations. However, as engines became more efficient, and Boeing began to stretch the fuselage of the 737, by the time the -300 went into production, this was no longer the case.
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Furthermore, the 727 came about as a response for demands for an aircraft that could fly between smaller airports with shorter runways, including those where climate or altitude hindered engine performance. It also catered for traffic at airports without cabin entrance ramps, hence the feature of the rear staircase.
This kind of ramp was made possible due to the fact that the engines were up by the tail, and not under the wings, thus placing the aircraft low enough to the ground. It was deployed when parking at a faraway ramp, or in the absence of a stair car. To begin with, this rear-door could be opened during flight, which led to a hijacker escaping that route in 1971 after a successful ransom demand.
Following the initial event, copycats performed no less than nineteen hijackings according to the exact same method. Clearly, the easy-access rear entrance that could be opened without fighting against the wind had become a liability. Engineers developed something called the Cooper Vane, which was named after the first hijacker to escape through the door. This prevented the door from being opened mid-air. However, most airlines opted to either seal off the stairs or decided to simply phase out the aircraft.
The 727 that became a house in the woods
While understanding the anachronistic elements that forced the 727 out of production in favor of more modern and efficient jets, some fans have found ways of hanging on to the aircraft. Like Bruce Campbell, a Portland-based aeronautics enthusiast who has made one into his home.
He bought the plane in 1999. Since then, he has kept the interior rather true to the aircraft’s flying days. However, he has upcycling parts of it into an innovative place of residence. The plane is propped up on concrete pillars in a serene wooded area. And the entrance? Why, through the rear-staircase, of course.
Did you ever fly on the 727? What was it like, and do you miss the aircraft? Could you imagine living in one? Let us know in the comments.