Based on the early 747 series, the Boeing 747-400 was virtually a completely new aircraft. And for a long time held the palm as the most capacious passenger aircraft.
At the Farnborough Airshow in 1984, Boeing demonstrated its new development, the Advanced Boeing 747 Series 300. The aircraft had an increased wingspan (but without vertical tips), reduced due to the active use of composites by 4989 kg weight, and increased flight range to 12955 km. The cabin for the crew of three was saved, and for the power plant, the customer could choose the engine option – General Electric or Pratt & Whitney brands. By May 1985, the new modification received the designation Boeing 747-400, but soon underwent some changes – the cabin was redesigned for a crew of two people.
The final “go-ahead” for launching the Boeing 747-400 in the series was given in October 1985, at the same time a start order for the airliner from Northwest Orient (Northwest Airlines) was received. The customer preferred the Pratt & Whitney PW4256 turbofan engine (then designated as PW4056), and at the same time the famous vertical wingtips appeared on the plane, and another fuel tank was placed in the tail. An alternative was the installation of Rolls-Royce RB.211-524D4D engines (then RB.211-524G) on a new machine, the first customers of which were Cathay Pacific (June 1986) and British Airways (end of 1986). New orders came from Singapore Airlines, KLM (the first customer for a machine with General Electric CF6-80C2 engines), and Lufthansa (the first customer for Combi).
The first 747-400, equipped with PW4056 engines, was pumped out of the Everett workshop on January 26, 1988, and took off on April 29, six weeks after the scheduled due to identified problems in the aircraft’s electrical system. A little later, two more cars joined the flight test and certification program. The first of them, equipped with CF6 engines, took off on June 27, 1988, and set the world record on the same day – the plane took off with a maximum take-off weight of 404815 kg. The third 747-400 was powered by Rolls-Royce engines and made its first flight on August 28, 1988. The Boeing management planned to complete certification in December 1988, but the process dragged on for various reasons. However, the identified shortcomings did not disappoint customers, and by the end of 1988, 168 orders were received from 16 airlines for the aircraft.
The Boeing 747-400 received an FAA type certificate on January 9, 1989, and the following month Northwest Airlines launched its new liner on the Minneapolis – Phoenix line. The first flights on the international flights of the Boeing 747-400 began on June 1, 1989 – on the New York – Tokyo line. The second customer of the new airliners was Singapore Airlines, which, after trial flights on May 30, 1989, put up an airplane named Megatop for daily flights to the London – Singapore line. The first Boeing 747-400, equipped with CF6 engines, entered KLM on May 8, 1989, and a few days later the German Lufthansa received its first car. On June 8, 1989, the first Rolls-Royce powered car entered the Cathay Pacific. The aircraft received a type certificate from the British CAA agency only a few days later.
Along with the passenger, other modifications of the Boeing 747-400 appeared. Thus, the convertible cargo-passenger version “Combi” and the “pure” cargo version were created. The first customer of the Boeing 747-400M Combi was Lufthansa, but then the company re-ordered the standard passenger cars and the real first customer and recipient of this modification were KLM (the first car was received on June 30, 1989). The first ex-plant of the full cargo Boeing 747-400F was Cargolux, which received its first aircraft on November 18, 1993.
The option of increased capacity 747-400D was created specifically for Japanese airlines, the liners were to be operated on regular routes between the largest Japanese cities. The first 747-400D was delivered to Japan Air Lines on October 10, 1991.
After the news about the beginning of the development by Airbus of a new, super-capacious airliner, which was assigned the working designation AZXX, the management of Boeing took steps to create a new modification of the aircraft based on 747-400 that could compete with the European giant. The work was carried out in the direction of increasing the capacity and flight range, as a result of which the passenger aircraft 747-400ER and cargo 747-400ERF appeared, which were more likely a response to the Airbus A340-600 launched on the market. Release 747-400ER / ERF was completed by October 2009 and customers began to “re-sign” on the model 747-8 or 777-300, although some of them still went to the competition, opting for the A380.
The Boeing 747-400 is a four-engine rocket-propelled low-wing with a classic tail. In its construction, mainly aluminum alloys were used, as well as titanium, composites, and high-strength steel. The fuselage is a semi-monocoque type, with frames (their pitch is 50.8 cm), stringers, and a working skin. The round fuselage with a maximum diameter of 6.5 m, its sections are connected by forked connectors and steel bolts. The windows of the passenger compartment are arranged in increments of 50.8 cm, like with frames, which makes it possible to flexibly layout the compartment. In the cockpit, glazing is formed by two curved front panels and four flat side panels. All ten doors of the main deck have a proprietary Boeing design. Doors open forward-outward with a 180-degree turn. The emergency ladder is attached directly to the door and in the closed position it is placed on the “combat platoon”, and under normal conditions is held by a safety device. In an emergency, the doors urgently open with the help of hydraulic cylinders, the ramps are automatically inflated, and when forced to land on water, they become liferafts.
Wing – swept – 37.5 degrees., Transverse V – 7 degrees., Installation angle – 2 degrees. The relative thickness of the profile is 13.44% in the root part – 7.8% in the middle and 8% at the ends of the wing. It has a three-spar design with ribs, stringers, and working skin, which is divided into a center section attached to the fuselage, and two half-wings. When assembling the wing box, special taper lock-type titanium bolts with a conical head were used to increase the fatigue strength of the structure. The wing is equipped with powerful mechanization. Between the fuselage and the internal engines, three-section Kruger shields are installed on the leading edge of the wing, and ten-section on the outer parts of the leading edge. It is interesting that the shields have a flexible skin and, when removed, are like a flat sheet, forming the lower surface of the wing. With the help of a complex system of pushers and rods when releasing the flaps, the skin is bent and, together with the nose of the leading edge of the wing, acquires a slat profile. Release and cleaning of the shields are carried out using a pneumatic actuator. When the thrust reverse turns on after landing, all flaps are automatically removed to avoid damage by a jet stream.
The Boeing 747-400 is equipped with three-slotted flaps with deflection angles of up to 33 degrees. In case of damage to the hydraulic system, the flaps can be released using an electric actuator. The tail is free-bearing. The keel of a two-spar design with honeycomb skin. The tips are made of fiberglass. The stabilizer is two-spar, with removable leading edges. Depending on the modification of the aircraft, it has different installation angles.
The Boeing 747 has all fuel options in seven tanks in the wing and fuselage. Their total volume is from 183380 to 210423 liters. Refueling is done through the necks located under the leading edge of each wing, between the external and internal engines. Each tank has three fuel pumps that supply fuel to the engine.
The control system is entirely booster, triple duplicated. To control the rolls are multi-section ailerons and interceptors. External sections operate only at low speed, to avoid large torque on the wing. The inner sections of the ailerons operate at cruising speed. On each wing, there are six sections of spoilers, their maximum deflection angle of 45 degrees. Two-section steering wheel with fiberglass honeycomb skin. The elevators are also two-section with fiberglass lining.
The Boeing 747 navigation equipment is largely determined by the customer, and above all, various radar systems. The standard equipment for all modifications of the aircraft includes VHF communication systems, HF communications, three instrument approach sets, two radio compasses, two radio range finders, and a flight data recording unit (black box). Unlike its counterparts, the Boeing 747-400 is equipped with a “glass” cabin with a complex of aeronautical equipment with color multifunction displays. This complex includes six screens measuring 20×20 cm. Two screens replace all conventional air navigation devices. The other two perform the functions of a range finder, a radar, and control the flight route. The remaining two displays display information about the operation of the engines and the status of all aircraft systems.
- Modification: Boeing 747-400
- Wingspan, m: 64.40
- Aircraft Length, m: 70.60
- The height of the aircraft, m: 19.40
- Wing Area, m2: 560.00
- Weight kg: empty loaded aircraft 175600; maximum take-off 396890
- Engine type: 4 turbofan General Electric CF6-80C2B5F (Pratt Whitney PW4062)
- Draft, kgf: 4 x 27945 (28710)
- Maximum speed, km / h: 965
- Cruising speed, km / h: 910
- Practical range, km: 13570
- Crew: 2
- Payload: 416 passengers in a 3-class configuration or 524 in a 2-class configuration.