Kraków 2012-05-02
History
314c Section 15.04.2005 year.
Boeing 757 in Poland.
Boeing 757.
In early 1978, Boeing Commercial Airplanes presented plans for three new aviation programs, the construction of communication aircraft; Boeing 757, Boeing 767, Boeing 777. (Back then, there was a letter in place of the second digit). Why three new constructions? To understand this, we have to go back to 1973. Then, in the free world, there was a fuel crisis. Its main symptom was the several-fold increase in fuel prices. As a result, ticket prices increased significantly. Many air carriers faced bankruptcy. Added to this was the fight against excessive noise emissions. As an example, we can cite the problems with the Concord plane at US airports. There was little that could be done with the aircraft already in service. New, quieter and more economical planes had to be built. As a result, the design offices started working on new structures. This is what Boeing did, and in Europe, design offices pooled their efforts to create the Airbus family of aircraft.
The first Boeing design was designated 7N7. It was derived from the design of the Boeing 727. The Boeing 727 was an aircraft designed for short and medium distances. He was extremely popular on tours in North America. It was a market hit. The most popular was the 727-200 variant for 189 passengers. Work on the new version of the aircraft began in 1970. It was supposed to be an enlarged (elongated) Boeing 727-300. Interest in this design was expressed by Unaited Airlines, which began to participate in the costs of the program. Project 727-300 was ready for launch in late 1975. Two versions have been developed: for 125 passengers with CFM56 or JT10D engines (thrust 3 x 100 kN) and for 180 passengers with CF6-32 engines (thrust 3 x 139 kN).
The progress in the field of the power unit meant that a set consisting of two engines (instead of three) was enough to drive such a large aircraft. At that time, engines suitable for the aircraft were developed by Rolls Royce (RB211-535 engines with a thrust of 148 kN). So the structure was completely redesigned. The power unit was placed under the wings. Constructions were marked with 7N7. Projects 727-300 and 7N7 coexisted for some time. After the initial development of the 7N7, Unaited Airlines' enthusiasm for the 727-300 subsided and the design was completely scrapped. Unaited Airlines has supported the 7N7 program. Admittedly, there were a few possible other buyers of the 727-300 aircraft, but the quantities were too small to start production.
It should also be remembered that the 7N7 project offered significant technological advances; Turbo-fan motors. New technologies in the crew cabin. Less weight. Improved aerodynamics. Significantly lower operating costs. In parallel, work was undertaken on a wide-hull structure with a transcontinental range 7X7 (later 767), which also made use of these novelties. The third design was to be a trans-Atlantic plane, equipped with three engines (At that time, the regulations required that the plane crossing the Atlantic Ocean had a minimum of 3 engines.).
On August 31, 1978, Boeing received its first 7N7 orders. Eastern Air Lines (USA) and British Airways (UK) ordered 40 7N7-200 machines (21 and 19 respectively). The contracts were concluded in March 1979 and then Boeing gave the structure the designation Boeing 757. Orders for the shorter 757-100 were not received. This capacity gap was filled by the Boeing 737. On March 23, 1979, Boeing announced that preparations for serial production had begun. The first metal cuts for the new aircraft began on December 10, 1979. Final assembly began in September 1981.
The designers predicted a reduction in fuel consumption by approximately 30 percent. (20 percent due to the use of the new powertrain, 10 percent from the aerodynamic improvements). Compared to 727-200. New wings were developed for the aircraft. New materials were used. The maximum take-off weight (MTOW) was set at 99,800 kg (220,000 lb). This translated into 5,000 kg more payload. Rolls-Royce RB211-535C engines were planned for the aircraft, because such a power unit was chosen by Eastern Air Lines and British Airways. It was the first instance of a US-built prototype fitted with engines manufactured outside the US. Rolls-Royce RB211-535C engines have a thrust of 2 x 166 kN. Customers could also choose Pratt & Whitney PW2037 with a thrust of 2 x 170 kN and General Electric CF6-32. The latter engine, however, was not chosen by any customer and was not offered afterwards.
During the work on the 757, he was structurally distant from the 727-200, and used the 767 solutions, which was a program ahead of him by several months. 1/3 of the drawings of the 757 program came from 767. Also, the cockpits of both aircraft were identical. Color monitors (CRTs) appeared on the dashboard, replacing most traditional electromechanical instruments. The position of the deck mechanic was also abolished. Importantly, the pilots of the 767, after a short training, could sit at the controls of the 757 and vice versa. The avionics and flight management system were identical. It was similar with installations. The new wings had less aerodynamic drag and larger internal tanks, and most of all had more lift. They are equipped with more efficient mechanization. Compared to the 727 wings, these had a much larger wingspan.
One of the last similarities to the 727 was the T-shaped tail. It was changed in mid-1979 to the conventional one. A derivative of this change was a larger rear passenger compartment. As a result, it was possible to place 239 seats in the cabin, which is 50 more than in the 727-200.
The construction of the prototype began in Renton. The Boeing 727 and Boeing 737 were produced here, which is why the Boeing 757 production line was also installed here. British Airways and Rolls-Royce lobbied to start the production of complete wings in the UK, but to no avail. Most of the 757's components were made at Boeing plants and other American companies; Rockwell International main fuselage components, Grumman wing flaps, Fairchild made leading wing edge strips. Over time, smaller parts of the planes were built outside the US.
The commencement of production of the 757 coincided with the construction of the last 727s ordered. This allowed the Renton plant to maintain production efficiency. The final assembly of the first 757 began in January 1981. The aircraft was designated Model 757 with registration N757A. The roll-out of the Boeing 757 took place on January 13, 1982. The first flight was made on February 19, 1982, a week before the scheduled date. The crew consisted of test pilot John Armstrong and test pilot Lew Wallick.
A copy of the N757A was later used in various tests. It had a rebuilt bow and an additional horizontal front tail.
At that time (February 1982), the company already had 136 orders from seven carriers.
The first 5 machines were included in the test program. The data obtained from testing the 767 aircraft accelerated the test program of the 757. The 757 was found to be 1,630 kg (3,600 lb) lighter than the design data. Fuel consumption was 3 percent lower than the estimated fuel consumption, extending the range by 370 km (200 nautical miles). The collected data confirmed that the 757 is the most fuel-efficient aircraft in the 1,000 nautical miles (+1,850 km) range. After collecting data from 1,250 hours of testing (with the Rolls-Royce RB211 engine), the aircraft was certified by the Federal Aviation Administration (FAA) on December 21, 1982, and on January 14, 1983, by the British CAA. The first user picked up the plane on December 22, 1982, about 4 months after the first 767 was delivered. The first 757 with Pratt & Whitney PW2037 engines, the first customer, Delta Air Lines, picked up on 5.11.1984.
Already the first weeks of operation, the Boeing 757 showed its advantage over the Boeing 727 and similar machines. It burned 42% less fuel than the 707 and 40% less than the 727. It was quieter. He was taking more payloads. Among the pilots, the revolt against the two-man crews was dying out quickly. The glass cockpit received positive feedback.
Despite a good debut, not many orders for the B.757 were received. There were several reasons. First of all, fuel prices have fallen. The second reason was the de-regulation of the US internal market. As a result, planes such as the MD-80 gained popularity. That's why Boeing has invested in other versions of the 757; 757-200 PF - for the transport of goods (1985), 757-200 M - passenger and cargo, popularly known as combi (1987).
At the end of the 1980s, the US regulations on noise emissions were tightened. As a result, between 1988 and 1989, airlines ordered 322 B.757 planes, which were much quieter than competitors. The B.757 also had the advantage of a range of 3,900 miles (7,220 km), which was a dream for the DC-9, DC-8 S, MD-80.
The Boeing 757 went to the European market as well as to China. Their carriers ordered 59 aircraft, making Boeing the largest air exporter outside the Middle Kingdom.
Due to the progress in the field of aircraft engines, from the beginning of the 1980s, the USA worked on relaxing the regulations for crossing the North Atlantic. As a result, initially selected versions of twin-engine commercial aircraft were certified, and then all twin-engine versions for ocean crossing. All with the basic regime consisting in the minimum distance to the nearest airport capable of receiving the aircraft. This is included in the ETOPS regulations. These changes caused Boeing to discontinue work on the third three-engine structure, which was to receive the designation B.777 (This designation was given to another aircraft a few years later.). In 1986, the FAA certified the B.757 with RB 211 engines to fly over the North Atlantic. In 1992, such a certificate was obtained by the B.757 model with PW 2000 engines.
On April 26, 1989, the Boeing Company entered into a contract to sell 370 aircraft to United Airlines. It was the largest contract in the history of aviation, valued at $ 15,740,000,000 (over 15 billion). The order included 120 737 and 60 757, with an option for a further 130 B.737 and 60 B.757. To meet these orders, Boeing has hired 670 skilled workers from Lockheed. At the beginning of the 90s, the production of the B.757 reached 100 machines per year, practically in one version. Little was said about the version with an extended hull that could take more passengers and take advantage of the machine's long range. There was also information about the B.757-200 X with extended range and possibly the B.757-300 X. Only the interest of European charter carriers influenced the commencement of further works. In September 1996, an order for 12 elongated machines had already been collected and announced at the Farnborough Showroom. The hull was lengthened 7.13 m (23.5 ft). The aircraft was designated B.757-300. It has not received such radical changes as the B.737 Next Generation, due to the desire to keep costs as low as possible. As a result, the design phase was the shortest in Boeing's history. Only 27 months passed from the first drawings to certification. The construction of the prototype started on May 31, 1998, and the first flight was made on August 2, 1998. The plane entered service with Condor Airlines on March 19, 1999.
However, only 55 B.757-300s were built, as many customers chose the B.767-200, which unexpectedly became its competitor.
The falling number of orders in 2000 threatened the profitability of production. The reason was changes in the market, mainly in Europe, due to the flourishing of low-cost lines. These carriers focused their attention on the Boeing 737 and Airbus A 320 aircraft.
Air 2000 and Continental Airlines have shown interest in the B.757-200 X. Boeing has re-examined the feasibility of building such an aircraft. The undercarriage was strengthened and the fuel tanks were enlarged. The range has increased to 9,260 km (5,000 nautical miles). But the program was suspended.
Further development consisted in converting passenger planes into cargo planes. This is how the 757-200 SF was created. In 2004, Boeing announced the definitive end of production of B.757 aircraft after building 1,050 units. The last plane left the production line on October 28, 2004, and after several months (November 28, 2005) it was handed over to Shanghai Airlines. So, the production of the Boeing 757 continued from 1981 to 2004. In 2002, the B.757-200 aircraft cost $ 65 million, and the B.757-300 aircraft cost $ 80 million.
Written by Karol Placha Hetman