By Luis Linares / Published February 6, 2015
American Airlines Boeing 727-200 at Washington Reagan National Airport: Photo by Luis Linares / AirwaysNews
February is a significant month in the history of one of the most popular airlines ever built, the Boeing 727. The 727 first flew on February 9, 1963 and entered service on February 1, 1964. Boeing announced the end of the program on February 1, 1983. From 1963 to 1984, Boeing delivered 1,831 examples. Join us on this Flashback Friday as we look back at the 21-year history of this legendary tri-jet.
Development and Design
As it has done with other commercial airliners, Boeing included key customers during the development phase of the 727. In the early 1960s, the dominant commercial jets were the Boeing 707/720 and the Douglas DC-8. American Airlines, Eastern Airlines, and United Airlines needed a jet capable of serving smaller cities, which generally had shorter runways.
American wanted Boeing to develop an efficient twin-jet, while Eastern wanted a tri-jet that could exceed the 60-minute time limited required for two-engine aircraft to fly to the closest airport in case of an engine malfunction for its Caribbean routes. This is better known as ETOPS (Extended-range Twin-engine Operational Performance Standards) today. United, which had one of its hubs in the “mile-high” city of Denver, felt a quad-jet would be necessary to operate in the high-altitude airport. All parties reached a compromise, clearing the way for Boeing to design a tri-jet. The company launched the 727 in 1960 and produced it at its Renton, Washington plant.
The rollout of the 727 prototype and a rare 727 brochure: Images: Courtesy of AirwaysNews
EXTRA: Inside Boeing’s Renton Factory
Boeing briefly considered a joint program with British manufacturer Hawker SIddeley, which was also developing a tri-jet, but eventually decided against it. The company also studied engines under development by Pratt & Whitney and Rolls-Royce. Pratt & Whitney offered the JT8D, which was heavier, but more powerful than the Rolls-Royce’s RB163. Influential airline executives, like Eastern Air Lines CEO Eddie Rickenbacker, pushed for the JT8D, which eventually won sole rights to power the 727.
The new aircraft would also would incorporate new high-light technology that would help it take off from runways as short as 4,500 feet (1,371 meters), which was a key specification desired by the airlines. Another innovation was the S-shaped intake duct for the tail-mounted middle engine. Furthermore, airlines also wanted more independence from ground facilities, which led Boeing to develop an integrated air stair in the rear. This air stair became part of pop culture in the early 1970s. Does the name D.B. Cooper sound familiar?
Other examples of new technology for the 727 include the auxiliary power unit (APU), which allowed air conditioning and electrical systems to operate independent from ground power units with at least one engine running. Boeing also developed a tail skid for the 727 as a safety measure, in case of over-rotation on takeoff. The manufacturer would also offer nose wheel brakes as an option to help reduce stopping distances by up to 490 feet (150 meters).
Entry into Service and Evolution
As it would do with the Boeing 757 almost 20 years later, Eastern became the first airline to fly the 727, on February 1, 1964. The aircraft was an immediate hit, especially because of its versatility that permitted using shorter runways, flying medium-range routes and flying to large population centers that had smaller airports. The original 727 seated up to 131 passengers in a single-class configuration.
Eastern Airlines Boeing 727-100: Image: Courtesy of Mark Trent
EXTRA: Boeing 727 History, Tech Manuals, and Memorabilia
Additional operating characteristics included a maximum takeoff weight (MTOW) of 170,000 pounds (77,000 kilograms). At MTOW, the airplane required 8,300 feet (2,500 meters) of runway. Moreover, the 727 could fly up to 2,300 nautical miles (4,300 kilometers). Boeing also retained a cockpit virtually identical to their first jet, the 707, which required two pilots and a flight engineer.
Boeing’s unprecedented use of Krueger flaps and leading-edge slats on the 727 contributed to its ability to use shorter runways and provided good stability at low speeds. However, some 727 accidents led to the conclusion that the maximum 40-degree flap setting could result in higher sink rates or stalls on final approach. Therefore, new procedures limited the setting to 30 degrees, and airlines installed a plate on the flap selector to avoid the 40 setting.
The initial 727 models are known today as the -100s, and Boeing delivered 571 of them. The -100 is a retroactive designation to separate the original 727 from the longer and more popular -200 series. Variants of the -100 included the -100C (passenger to cargo convertible version) and the -100QC (“quick change” version between passenger and cargo configurations). The -100QF (quiet freighter) would be later designed for UPS in order to meet more stringent noise standards. This model was unique since it used Rolls-Royce Tay turbofan engines. Furthermore, the C-22 became the military transport version of the -100.
In 1965, Boeing launched what would become the most common variant (1,245 deliveries) of the 727, the series -200, which had its maiden flight on July 27, 1967 and entered service with Northeast Airlines on December 14 of that year. The length of the -200 is 153 feet, 2 inches (46.69 meters), 20 feet (6.1 meters) longer than the -100. It retains the same 108-foot (33 meter) wingspan and 34-foot (10 meter) height of the -100.
AVENSA Boeing 727-200 at Miami International Airport and Aces Boeing 727-200 at Barranquilla Ernesto Cortissoz International Airport: Photos by Luis Linares / AirwaysNews
The -200 upgraded from the JT-8D-1 to the JT-8D-9 engine, which provided an additional 500 pounds (2 kiloNewtons) of thrust from the original 14,000 pounds (62 kiloNewtons). This eventually allowed for an MTOW of 184,000 pounds 83,800 kilograms). Boeing also built one -200C version to allow passenger to cargo conversion. The -200 could seat 145 people in a two-class configuration and 189 in single-class, and it could fly up to 1,700 nautical miles (3,100 kilometers).
Starting with the 881st 727, Boeing introduced an improved -200 version, known as the -200A (“Advanced”), which was powered by JT-8D-17R engines with 17,400 pounds (77,000 kilograms) of thrust each that permitted an MTOW of 209,500 pounds (95,000 kilograms) with a range of 1,900 nautical miles (3,500 kilometers). In addition, an optional version allowed for a 2,600-nautical mile (4,800-kilometer) range. This version also offered a -200F model exclusively for FedEx cargo operations, and it included a strengthened fuselage structure with no windows, and a main deck freight door. There was also a C-22C military transport offering.
Boeing 727-200A technical summary: Image courtesy of AirwaysNews collection
Flying into the Sunset
In 1978 Boeing launched the twin-engine 757 as a 727 replacement. As twin-engine technology evolved, ETOPS restrictions eased and fuel efficiency improved. Moreover, the newer twins did not require a flight engineer. Boeing announced the end of the 727 program on February 1, 1983, and the last 727 delivery took place in 1984. Since the 757 was larger, the most common 727 replacements eventually became the 737-800 and Airbus A320.
The 727’s use of low bypass turbofans meant it was a very noisy aircraft. Hush kits were offered as noise restrictions increased. Upgrade options resulted in a “Super 27” variant that used the JT8D-217 and -219 engines on the sides. These engines were used by the McDonnell Douglas MD-80 family. The center engine could not be replaced because of the duct’s narrow diameter; hence that engine still required a hush kit. Furthermore, Valsan Partners offered winglets for efficiency and slight noise improvements. Unfortunately, the post-September 11 economic environment sped up the phasing out of the venerable 727.
A private, and currently active Super 27, belonging to Canadian fashion executive Peter Nygård, parked at Fort Lauderdale-Hollywood International Airport: Photo by Luis Linares / Airways News
Today, there are still some 727s in service, mainly for scheduled and charter cargo operations, mainly in Brazil, Canada and Colombia. In addition, Iran Aseman Airlines still uses the 727 for passenger operations. There are also private and government/military operators around the world. The original market forecast for the 727 was 250 aircraft. The 1,831 deliveries and the fact that the 727 was the best-selling airliner during the first 30 years of the commercial jet age turned this great airplane into one of the giants of aviation history.
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Contact the author at luis.linares@airwaysnews.com
Contact the editor at benet.wilson@airwaysnews.com
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