Kraków 2016-09-23
An outline of the history of air navigation 1980-1990.
Supersonic passenger airplanes.
Part 3.
Constructions after 1972.
In the USA in 1972, an era came to an end. The 1966 contest winner, the Boeing 2707-200 had to significantly redesign its design to create the Boeing 2707-300 that closely resembled the Lockheed L-2000 competitor. Ten years of work have not been completed successfully. This does not mean, however, that American companies have completely abandoned supersonic commercial aircraft. A new stage has come.
McDonnell Douglas. Projekt AST.
Despite the collapse of the SST program, other US aviation companies returned to the concept of a supersonic passenger plane in the 1970s. The most promising was the project by McDonnell Douglas labeled AST (Advanced Supersonic Transport). The plane was to take 237 passengers on board, had a range of 4 400 NM (8 148.8 km) and a cruising speed of Ma 2.2.The project was more conservative than its predecessors. The classic layout was used. Wings with a double delta contour, equipped with rich mechanics. Flaps or gills on the leading edge. On the trailing edge; rudder ailerons and flaps. Breakers on the upper surface of the airfoil. Floating horizontal tail with division into rudders and fins. The concept of the field rule was still used. Therefore, the aircraft fuselage acquired a constriction. In addition, the fuselage axis was to be bent in the shape of a flattened S (sloped front and raised rear). This arrangement made it possible to reduce the airframe drag, and thus to use less powerful engines.
Interestingly, the cruising speed of the order of Ma 2.5-3.0 was abandoned. This was dictated by the limitation of the increase in the outside temperature of the aircraft skin, and thus the desire to use cheaper materials (aluminum alloys) instead of expensive titanium.
The program ended before he got off the drawing board.
Aerospatiale. 1985.
Initially, French designers focused on developing a new variant of the Concorde plane, which was designated Concorde B. The plane was to receive mechanization on the leading edge. The plane was supposed to use 10% less fuel, thanks to which the range could be 7,230 km, or 930 km more. A raised tail was considered to be able to increase the angle of attack during take-off and landing. Noise reduced by 10-12 dB.
Aerospatiale and British Aerospace. 1985.
ATSF project (Avion de Transport Supersonique Futur).
The design of the French company Aerospatiale, designated ATSF (Avion de Transport Supersonique Futur), was based on the experience gained over 15 years since the flight of Concorde. The British company British Aerospace also joined the program and the project was described as a second generation supersonic aircraft. However, this time, the overriding goal was to see if taking any possible risk would be profitable? Will unexpected difficulties from environmentalists again be encountered. (We remind you that ecology is not the same as environmental protection). The designers, knowing the difficulties associated with the construction of the Concorde structure, decided to stay within the cruising speed limits of Ma 2.0 – Ma 2.2. Additionally, the limits of the cruising speed of the subsonic range were set at Ma 0.95. The focus was on increasing the number of passengers on board. Their number was to be 200-300 people. Range extension to around 8,000 km, of which around 1,000 km will be covered at subsonic speed. In the construction, already known, new materials, such as carbon composites and plastic forming of titanium, were to be used as widely as possible. Already at the programming stage, the plane was supposed to be 12-16% quieter than the Concorde, depending on the flight phase. The ATSF was to be 50% more technologically advanced than Concorde. The plane was to be electronically controlled via fly-by-wrie systems. Hyper-bearing devices, that is, the rich mechanization of the lobe, were to be used extensively. The wandering of the center of pressure was also supposed to be compensated by tilted pearlings. Screens with selective presentation of information in the flight deck. The aircraft crew is limited to two pilots (there are three in Concorde). The novelty is the new drive idea; at subsonic speed, the motors work as two-flow, and after crossing the sound barrier, they operate as single-flow.
The range of the new aircraft program ran until 2000. Three capacitive categories have been created; 210-300 seats, 350-400 seats and 500-600 seats. The ATSF project fell into the first category.
By 1985, the ATSF was in the pre-design phase. His figures were estimates at the time; Max weight 220,000 kg. The area of the patch is 500 square meters. The four engines are placed under the wings in individual nacelles. This will ensure better access when servicing and replacing them. Fuel consumption per passenger per kilometer was to decrease by 50%. Of course, the ATSF plane was to use classic airports and their runways, as well as the airport equipment used at that time.
The flight of the ATSF aircraft was to take place at the turn of the 1980s and 1990s. It all depended on the interest of possible users. However, the interest was minimal. The program was mainly implemented by the French company Aerospatiale. Here, laboratory tests were carried out, the first drawings were drawn and the models were tested. The British were ready to go to work on the same terms as with the Concorde program. Despite this, the French looked across the Great Water, looking for companies willing to cooperate. No one was found.
Lockheed.
Lockheed also returned to work on a commercial supersonic aircraft in the mid-1980s. She conducted research and pre-design work on an aircraft for 230 passengers, with a range of 4 800 NM (7 724 km) and a cruising speed of Ma 2.7. Two variants were considered; drive with classic aviation fuel or liquid hydrogen. In the first case, the fuel mass would be 53% of the total weight of the aircraft, the payload would be 6% of the total weight of the aircraft, or 340,000 kg. In the second case, the total weight of the plane would be only 173,000 kg. In this case, the weight of the fuel is also 53% of the total, and 12% is the payload.
Sub-orbital airplanes. 80-years of the 20th century.
Sub-orbital planes, otherwise known as hypersonic, are a group of commercial machines that have not even had a single prototype. Despite the fact that there are some promising projects, the expected time of their entry into service is the beginning of the 21st century. Nay. In the aviation world, the catchy name – Orient Ekspres – quickly stuck to these planes.
The success of the American Space Shuttle drew the constructors’ attention to the possibility of building communication aircraft with a cruising speed of Ma 5.0 – Ma 7.0, which would fly at an altitude of 30,000 m (and possibly even 100,000 m), and within 90- 120 minutes would reach any airport on Earth. Importantly, there were technical possibilities to implement such projects.
Aerodynamically, these constructions have already been worked out. In-flight aerodynamic heating has also been mastered; by using heat-resistant alloys (metal, ceramic, carbon, etc.) or active cooling systems. The power units were also dealt with; There were designs that combined a classic turbojet engine, a jet engine and a rocket engine in one power unit. Fuel issues (upgraded aviation kerosene or liquid hydrogen) have been resolved.
Despite many paper projects, no commercial orbital plane was created. The reason was the lack of interest in these air carrier projects. Eventually, the programs were closed at the end of the 20th century.
Written by Karol Placha Hetman