The 727 is one of the most successful commercial aircraft in aviation history. Well over 1700 were produced between 1963 and 1984. As of November 1995, the majority of those produced are still used in regular commercial service.
Boeing also wanted to take a larger share of the short-haul aircraft orders that in the mid-to-late 1950's appeared to be going only to turboprop aircraft such as the Lockheed Electra, Vickers Vanguard (a larger version of the smaller but better-known Viscount), and the Fokker F-27 Friendship.
Also of concern to Boeing was an effort by Convair (General Dynamics of San Diego) to market a four-engine jet aircraft called the Convair 22 (later called the Convair 880), quite similar in configuration to the 707 but with a smaller capacity and shorter range. Naturally, Boeing's archrival Douglas was also toying with varous short-haul jet designs of its own, as was Hawker Siddeley of Great Britain, which had announced plans for its short-haul ``Trident'' jet.
Before the 727 design was finalized, in order to meet the threats posed by its competitors, Boeing created a smaller derivative of the 707 called the 720. (The 720 is discussed in another section.) Strategically speaking, the 720 was produced as a preemptive strike against Convair and others until the 727 was ready for production. As things turned out, however, the 720 developed its own market niche distinct from that of the 727.
By 1960 Boeing had firmed up the basic design characteristics of the 727. It would be a three-engine jet, with two engines mounted on each side of the fuselage and a center engine buried in a ``T Tail'' stabilizer, which some say was ``borrowed'' (or stolen) from the British Trident design. The idea of rear-mounted engines also was not unique to Boeing, as the French-built Caravelle twin jet had already employed this concept, albeit with a different tail design. In fact, the Caravelle had already been in scheduled service for one year before the 727's design was finalized. Particularly alarming to Boeing was that United Airlines had ordered 20 Caravelles for delivery starting in 1961.
A highly advanced wing was designed to enable the 727 to operate at airports with short runways that previously could only be served by either propeller or turbo-prop aircraft. New were full length ``leading edge'' and triple slotted flaps. Also new (for Boeing) was a rear ``ventral'' stairway located below the tail, also similar to that of the Caravelle. Powerplants would be a variation of Pratt & Whitney's new JT8D fan jets, which were just being offered on its latest 707 models. The front landing gear configuration was very similar to the 707's. The main gear was a twin tire set-up on each wing.
From a plane spotter's perspective, the other unique attribute of the 727 was its sharing of cockpit and cabin width dimensions with the 707. Most turboprop aircraft at the time had either five- or four-abreast seating. Boeing believed that if it could ``graft'' the basic six-abreast 707 cabin dimensions on to the 727, many 707 operators would be attracted to the commonality and higher passenger and cargo capacity.
The 727 represented Boeing's first attempt to produce a ``family'' of jet aircraft after the 707/720 series: an aircraft with a distinct mission yet with many features that were common from an operational perspective. Earlier Boeing designs for the 727 were more Caravelle-sized (70-90 passengers) but matured into configurations of from 94 to 130 passengers, depending on the class mix. Aircraft range also increased to 2200 miles, just short of transcontinental capability.
Eastern Airlines was first to order the 727 in 1960, followed shortly by United, TWA, Lufthansa, and American. The great success of its 707 series aircraft resulted in many 707 carriers ordering 727's,and between 1960 and 1962 Boeing received orders from over 50 carriers, all before the prototype had flown.
As it had done on its 707 aircraft (in 1962), Boeing offered ``combination'' passenger/cargo versions of the the 727. While the combination model 707's were generally identified as ``C'' models, Boeing decided to call the 727's combination version QC, or ``Quick Change.'' Like the 707, a QC model was fitted with a large cargo door just aft of the main passenger entry door. (No pure freighter version was offered initially.) Unlike the 707, however, the 727 QC also came with specially designed floors which permitted rapid removal of seats for cargo loading. United was the first U.S. carrier to order QC models and they were delivered between 1965 and 1966.
Aside from the increase in fuselage length, no other dimensions were changed. Also unchanged from initial version was engine thrust, despite the heavier weight. Since Boeing had equipped the -100 series with somewhat overpowered 14,000-lb. P & W JT8D fan jets, it was thought that the same engines would be adequate for the -200 model. Early operators of the -200 soon found that this was not the case. Pilots complained that power was ``marginal'' in certain conditions and generally sluggish most of the time. As a result, more powerful engines were offered shortly thereafter.
From a ``head on'' view, one physical attribute that allows spotters to quickly distinguish a 727-100 from a 727-200 is the shape of the number 2 (center tail mounted) engine inlet opening. On the 727-100, the opening of the engine has a slight oval shape (with a vertical bias), while on the 727-200 series the opening is a round symetrical shape and is about 6 inches higher (from the fuselage) than in the -100.
First flight of the -200 was in 1966, and revenue service began in late 1967 with Northeast. Other early operators of the -200 series included American, TWA, Eastern, and United. The -200 was also offered in the QC configuration, but still not as a pure freighter model.
By 1970 almost all 727 orders were for the -200 model, so Boeing decided to stop production of the shorter -100 series and focus on improving the -200.
In 1982, Boeing responded to a request from Federal Express for a pure freighter model of the 727. In fact, the 727-200F model was the last 727 version built of the 727 by Boeing between 1982 and 1984, when production ceased. Externally, the 727-200F is identical to the 200QC, except that there are no passenger windows, overwing emergency exits, or rear service doors. Federal Express was the only carrier to order the -200F, although by the mid 1990's, several had been sold to other express and freight organizations.
Many 727-100 aircraft are being scrapped, although a significant number wind up with third-world carriers as either freight or passengers models. Except for the earliest -200's, most -200's are finding homes as freighters and passenger carriers, both in the U.S. and abroad. Few -200's have been scrapped thus far.
Also on some early version -200's, an additional ``mid-sized'' exit door appears on the port side, located halfway between the main passenger entry door and the overwing emergency exits. Apparently this extra door was installed because of some Federal exit requirement for aircraft with high capacity all-coach seating, but for some reason it was not required later because almost all carriers that had 727-200's with this extra door sealed and plugged them within several years of the original service date.
A rare sighting is 727-100 with additional rear service doors installed in a position similar to that of a -200, that is, just forward of the rear engines. At least two Central American airlines which received second-hand -100's had these doors installed after delivery. I recall seeing these aircraft at Miami International in the late 1980's, and I must say they looked strange: it is akin to installing two extra doors on a Volkswagen Beetle without lengthening it. One can only guess why they were installed, but perhaps it was necessitated by the very high density all-coach seating that they reconfigured the aircraft with.