Boeing 757

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If you ever go on holiday to an exotic place that’s not too far from home (within about four hours flying time), then chances are you’ve probably flown aboard this, the Boeing 757, the weapon of choice for many low-cost carriers to whisk passengers away to their relatively inexpensive vacation!

The origins of the Boeing 757 go back to the early 1970’s, when following the launch of the legendary Boeing 747, the company desired the creation of an aircraft that would operate higher-capacity short to medium routes, essentially an onward development of the Boeing 727. By the time plans were being considered, the 727 had become the best-selling commercial jetliner in the world, and the mainstay of the U.S. domestic airline market. Initial studies focused on improving the 189-seat 727-200, the most successful 727 variant, with two approaches being considered: a stretched 727-300, and an all-new aircraft code-named 7N7. The former was a cheaper derivative using the 727’s existing technology and tail-mounted engine configuration, while the latter was a twin-engine aircraft which made use of new materials and improvements to propulsion technology which had become available in the civil aerospace industry.

Input and incentive for the proposed 727-300 came from United Airlines, and Boeing was considering a launch for the aircraft in late 1975. However, after United was shown the 7N7 concept, it’s interest instead turned towards this design. Although the 727-300 was offered to Braniff International Airways and other carriers, customer interest remained insufficient for further development. Instead, airlines were drawn to the high-bypass-ratio turbofan engines, new flight deck technologies, lower weight, improved

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American Airlines is among the largest operators of the 757, their fleet increased in size following the merger of US Airways.

aerodynamics, and reduced operating cost promised by the 7N7. These features were also included in a parallel development effort for a new mid-size wide-body airliner, code-named 7X7, which became the 767. Work on both proposals accelerated as a result of the airline industry upturn in the late 1970s.

Originally, two variants of the 7N7 were derived; the -100, with seating for 160, and a -200 with room for over 180 seats. New features included a redesigned wing with engines underneath, and lighter materials, while the forward fuselage, cockpit layout, and T-tail configuration were retained from the 727. Boeing planned for the aircraft to offer the lowest fuel burn per passenger-kilometer of any narrow-body airliner. On August 31st, 1978, Eastern Air Lines and British Airways became the first carriers to publicly commit to the 7N7 when they announced launch orders totalling 40 aircraft for the 7N7-200 version. These orders were signed in March 1979, when Boeing officially designated the aircraft as the 757. The shorter 757-100 did not receive any orders and was dropped; 737s later fulfilled its envisioned role.

The main purpose of the 757 was to outperform the earlier 727, but also to be much more efficient in the face of the Energy Crisis. Design targets included a 20% reduction in fuel consumption from new engines, plus an additional 10% from aerodynamic improvements, versus preceding aircraft. The maximum take-off weight (MTOW) was set at 220,000 pounds, which was 10,000 pounds more than the 727. The 757’s higher power-to-weight ratio allowed it to take off from short runways and serve airports in hot and high climates, offering better takeoff performance than that offered by competing aircraft. Competitors needed longer takeoff runs at airports at higher elevations, with higher ambient temperatures and thinner air. Boeing also offered options for higher payload capability.

The twin-engine configuration was chosen for greater fuel efficiency versus three- and

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1985 757-232 N608DA is now preserved by Delta Air Lines at their Heritage Museum in Atlanta.

four-engine designs. Launch customers Eastern Air Lines and British Airways selected the RB211-535C turbofan built by Rolls Royce, which was capable of 37,400 pounds-force of thrust. This marked the first time that a Boeing airliner was launched with engines produced outside the United States. Domestic manufacturer Pratt & Whitney subsequently offered the 38,200 pounds-force thrust PW2037, which Delta Air Lines launched with an order for 60 aircraft in November 1980. General Electric also offered its CF6-32 engine early in the program, but eventually abandoned its involvement due to insufficient demand.

Gradually, as development progressed, the aircraft’s 727 origins were slowly dropped as elements from the 767 were adopted. To reduce risk and cost, Boeing combined design work on both twinjets, resulting in shared features such as interior fittings and handling characteristics. Computer-aided design, first applied on the 767, was used for over one-third of the 757’s design drawings. In early 1979, a common two-crew member glass cockpit was adopted for the two aircraft, including shared instrumentation, avionics, and flight management systems. Cathode-ray tube (CRT) colour displays replaced conventional electromechanical instruments, with increased automation eliminating the flight engineer position common to three-person cockpits. After completing a short conversion course, pilots rated on the 757 could be qualified to fly the 767 and vice versa, owing to their design similarities.

Production of the 757 took place at the Renton factory alongside the 707, 727 and 737, with a new assembly line being constructed at the plant. The prototype 757 rolled out of the factory on January 13th, 1982, the aircraft equipped with with RB211-535C engines. This plane completed its maiden flight one week ahead of schedule on February 19th the same year, but the flight was affected by an engine stall, following indications of low oil pressure. After checking system diagnostics, company test pilot John Armstrong and co-pilot Lew Wallick were able to restart the affected engine, and the flight proceeded normally thereafter. Following the maiden flight, an intensive test period carried out seven days a week was adopted. By the time the 757 made its first leap into the air, the aircraft had received 136 orders from seven carriers, namely Air Florida, American Airlines, British Airways, Delta Air Lines, Eastern Air Lines, Monarch Airlines, and Transbrasil.

After 1,380 flight test hours, the RB211-powered 757 received U.S. Federal Aviation Administration (FAA) certification on December 21st, 1982, followed by UK Civil Aviation Authority (CAA) certification on January 14th, 1983. The first delivery to launch customer Eastern Air Lines occurred on December 22nd, 1982, about four months after the first 767 deliveries. The first 757 with PW2037 engines rolled out about one year later, and was delivered to Delta Air Lines on November 5th, 1984.

The Boeing 757 was an immediate success both in the USA and abroad, with a majority of mainline carriers taking on at least 10 examples. In the UK, British Airways used the 757 to replace the ageing Hawker Siddeley Trident 3B trijets, while charter carriers Monarch Airlines and Air Europe also began 757 operations later that year. In America itself, American Airlines, United Airlines, Continental Airlines, Delta Air Lines, Northwest Airlines and many more were, and are, the proud owners of these highly reliable jet airliners, which very quickly garnered a reputation for their ability to clock up hundreds of hours of flight time between major maintenance periods. Airlines also appreciated the aircraft’s two-crew member flight deck, removing the need for the Flight Engineer and reducing the complexity of the flying experience.

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An early production 757-300 in Boeing house colours during its initial testing.

However, these proud owners weren’t exactly climbing over themselves initially to buy up 757’s. In fact, during the 1980’s, the 757 didn’t actually garner that many sales, which made it something of a rarity in its early years. A consequence of declining fuel prices and a shift to smaller aircraft in the post-deregulation U.S. market made it noncompetitive against smaller, cheaper aircraft such as the 150-seat narrow-bodied McDonnell Douglas MD-80. Hope for the aircraft came in November 1983 when Northwest Airlines placed orders for 20 aircraft, which averted a costly production rate decrease.

In December 1985, a freighter model, the 757-200PF, was announced following a launch order for 20 aircraft from UPS Airlines, and in February 1986, a freighter-passenger combi
model, the 757-200M, was launched with an order for one aircraft from Royal Nepal Airlines. The freighter model included a main deck cargo hold and entered service with UPS in September 1987. The combi model could carry both cargo and passengers on its main deck and entered service with Royal Nepal Airlines in September 1988.

The 757’s time to shine came in around 1989, when noise regulations and increasing hub congestion due to the use of smaller aircraft meant that airliners such as early Boeing 727’s and 737’s were becoming undesirable. From 1988 to 1989, airlines placed 322 orders, including a combined 160 orders from American Airlines and United Airlines. By this time, the 757 had become commonplace on short-haul domestic flights and transcontinental services in the U.S., and had replaced ageing 707s, 727s, Douglas DC-8s, and McDonnell Douglas DC-9s. The 757 found a niche flying out of airports with stringent noise regulations, such as John Wayne Airport in Orange County, California, and airports with aircraft size restrictions, such as Washington National (now Ronald Reagan) Airport near downtown Washington, D.C. The largest U.S. operators, Delta Air Lines and American Airlines, would ultimately operate fleets of over 100 aircraft each.

The 757’s abilities were furthered however by the creation of the 757-300, which was launched in 1996 as a stretched version of the increasingly popular airliner. The new model was a 23.4-foot stretch of the 757-200, resulting in room for 50 more passengers and nearly 50% more cargo. The type’s design phase was intended to be the shortest in its manufacturer’s history, with 27 months from launch to certification. Due to development and cost concerns, radical upgrades such as a Next Generation 737-style advanced cockpit were not implemented. Instead, the stretched derivative received upgraded engines, enhanced avionics, and a redesigned interior. The first 757-300 rolled out on May 31st, 1998, and completed its maiden flight on August 2nd the same year. Following regulatory certification in January 1999, the type entered service with Condor on March 19 that year.

In addition to commercial aviation, the 757 has also found its way into military service.

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A 757-300 under the ownership of Condor, seen on short final.

The most notable military 757 is the C-32A, a selection of four VIP-configured 757-200s used by the USAF for transporting of the Vice President of the United States under the callsign Air Force Two. The C-32As are outfitted with a communication center, conference room, seating area, and private living quarters. The first C-32s were delivered in 1998 and replaced the nearly 40 year old, Boeing 707 based C-137 Stratoliner transports.

Sadly, the Boeing 757, like many airliners, has not had a smooth ride in terms of accidents, and, as of October 2015, has been involved in 29 aviation occurrences, including 8 hull-loss accidents. Seven crashes and 11 hijackings have resulted in 574 occupant fatalities.

The first accident involving the 757 wasn’t technically its fault. On October 2nd, 1990, a China Southern Airlines 757 was struck at the gate by a Xiamen Airlines 737 which had been hijacked. A last minute scuffle in the cockpit caused the 737 to veer off course, smash through the 757 before crashing and exploding itself. The result was the deaths of 46 of the 122 people on board.

One of the more notable incidents was American Airlines Flight 965 on December 20th, 1995. The aircraft crashed into a mountain in Buga, Colombia while attempting to land at Cali after the pilots became disorientated. The result was the deaths of 151 passengers and eight crew members with four survivors.

Another notable incident involved a 757 operating DHL Flight 611 near Überlingen, Baden-Württemberg, Germany, on July 1st, 2002, when due to misinformation by Air Traffic Control, the aircraft collided with a Bashkirian Airlines Tupolev Tu-154, with the loss of two on board plus 69 on the Tupolev.

There have also been two instances of 757’s crashing due to improper avionics readings disorientating the pilots, these being Birgenair Flight 301 on February 6th, 1996, and Aeroperú Flight 603 on October 2nd the same year. Birgenair Flight 301 suffered various control malfunctions followed by a stall after departing Puerto Plata, Dominican Republic, crashing into the Atlantic with the loss of all 189 aboard. Aeroperú Flight 603 crashed off the coast of Pasamayo, Peru, after instrument failures resulted in the aircraft flying too low and hitting the Pacific, with the loss of 70 souls aboard. In the first instance, investigators found that the aircraft had been stored without the necessary covers for its pitot tube sensors, thus allowing insects and debris to collect within, while in the Aeroperú accident, protective tape covering static vent sensors had not been removed.

However, the most notable crashes of the 757 were on September 11th, 2001, when United Airlines Flight 93 and American Airlines Flight 77 were hijacked by Islamic extremists and crashed as part of a massive terrorist attack on the USA. Flight 77 reached its target, slamming into the front wall of the Pentagon, killing all 64 on board and 125 on the ground, while Flight 93 crashed in rural Pennsylvania after the passengers attempted to take back the plane, killing all 44 on board.

Today, Boeing 757’s continue to be the backbone of a majority of major airlines. Production of the entire 757 series ended in November 2005, with the final aircraft, B-2876, being delivered to Shanghai Airlines. Unlike the larger 767, many of the earlier 757-200’s continue to maintain a strong presence in the aviation industry, primarily in the fleets of charter airlines and low-cost carriers. While some larger carriers such as British Airways have retired their fleets, most operators like American Airlines and United Airlines have these comparatively old aircraft still working a pivotal function on both the domestic and international circuit.

I feel that, even though it has been out of production for 12 years, the Boeing 757 is destined to remain in front-line service for many years to come, even with the prospect of the Boeing 787 and larger 737’s on the horizon.