WO1998030444A1 - Supersonic aircraft - Google Patents

Abstract

The invention relates essentially to long-haul business aircraft, designed to be used for business trips by heads of state, municipal bodies, large companies, business people and so on, as well as for the urgent delivery of light cargo, with the intent to save substantial amounts of time, in all circumstances, compared with other forms of transport. The essence of the invention consists in a supersonic business aircraft whose aerodynamic design results in a lighter aircraft structure, and the attainment of high performance levels during cruising; the aircraft can also employ the same aerodromes used by subsonic craft. The fuselage is integrated with the wing system, and the middle frame section is substantially round. The engines are disposed in a single engine nacelle, which is integrated with the tail section of the fuselage; the fuselage does not extend beyond the engine nozzle. The vents are located under the wing section, and their forward edges disposed at a distance of 0.6...0.8 of the length of the fuselage commencing from its nose. The lower surface of the nacelle is more or less equidistant from the lower surface of the wing, and the transverse surfaces are disposed parallel to the aircraft's plane of symmetry. Each half-wing comprises three portions; the relative spans of the root and intervening wing portions are fractions of half the wing span, and have values of 0.2...0.35 respectively at the points of fracture. The sweep angles at the forward edge, commencing with the leading edge of the wing, are 70°-82° for the root portion, 55°-65° for the intervening portion, and 35°-55° for the end portion. The sweep of the rear edge of the end and root portions is nearly nil, and the value of the root wing span is 0.8...1.0 of the length of the fuselage. The flying time of the aircraft over a distance of 6000 km does not exceed 4 hours, and operating costs are comparable to those of subsonic craft. The aircraft can take off and land from the same aerodromes as subsonic models.

Description

\УΟ 98/30444 ΡСΤ/ΙШ97/00001

SΒΕΡΧZΒUΚΟΒΟY SΑΜΟLΕΤ.

ΟBLΑSΤΕΧΗIΚI. The invention relates primarily to long-range administrative (business) aircraft intended for business trips by heads of state, municipal authorities, large enterprises, businessmen, etc., as well as for emergency delivery of small cargo in order to save time in all cases, compared to the use of other means of transport.

THE PREVENTING URGE OF TECHNIQUE. All existing administrative aircraft have subsonic flight speeds. When flying a distance of 6000...7500 km, long-range subsonic aircraft such as the Falcon, Challenger, Holstein, etc., spend almost 10 flight hours. to reduce the physiological and psychological stress on passengers during a long flight, these aircraft are equipped with comfortable cabins, the dimensions of the cabins provide the ability to move around the cabin in full-time. Considering that the entire business trip is long-distance

6000...7500 km, taking into account the time required for rest. takes 2..3 days, it seems very important to provide the opportunity to make one-day business trips, when leaving home in the morning, in the afternoon you can hold a meeting at the place of flight and return home in the evening. This mode of travel will facilitate the passenger's physiological tolerance to the flight, will not disrupt the usual rhythm of life and will not require unnecessary time expenditures to adapt to the local time at the points of arrival and return. The solution to this problem is possible by creating supersonic business aircraft with a cruising speed of 1900...2100 km/h. The project of the supersonic administrative aircraft S-21, developed by the OKB im. P.O. Sukhoi together with the American company "Gol'strim" (see "Moscow International Aerospace Salon", Moscow, "Afrus" publishing house, IPTK "Logos", 1995). As indicated in the source, the S-21 has a takeoff weight of about 52 tons. and is designed for passenger transport of 8...10 passengers at a range of up to 7400 km. The aircraft has aerodynamic \УΟ 98/30444 ΡСΤ/ΙШ97/00001

2

assembly containing a fuselage with a significantly protruding rear fan, with a double skewer κροοκκκκικκκα, whole-body gonorrhea, unilateral veticular οπορρτρν and ττρi engine gondolas, two of One of the vents is located under the wing, and the third is in the tail section of the fuselage. The maximum dimensions of the passenger cabin of the S-21 aircraft in cross-section are 1.86 m in height and 1.6 m in width.

However, the high level of sonic boom (more than 45 Pa) does not allow flights over land at supersonic speed. In this regard, the area of use of the S-21 as a supersonic aircraft is limited to flights across the ocean. In addition, the operating costs for the S-21 are more than twice those of its subsonic analogues due to its significantly higher cost (40-50 million dollars instead of 18-25 million dollars) and approximately twice as high fuel consumption. The closest thing to this invention is a light-sound plane with a fan of greater shape (see US Patent Νο4828204, 1989), containing the fuselage, the front section of which is located behind the fuselage, the central section constructively is united with the wing, the rear section of the fuselage projects beyond the rear edge of the wing. The front section of the fuselage and part of its central section have inwardly inclined side walls that form a surface with a uniform curvature in the longitudinal direction. The central section has a lower surface articulated with the lower surface of the wing in such a way that the fuselage does not protrude below the wing anywhere. Two engine nacelles, mounted on the lower surface of the wing on both sides of the fuselage, have air intakes located behind the front wing section. The aircraft contains two vertical keels, each of which is mounted near the corresponding wing tip, above and below the wing plane. At each end there is additional information that can be discussed further The axle is controlled, ensuring aircraft control in terms of airfoil and pitch.

Obviously, the aerodynamic configuration is optimized for the supersonic cruiser flight mode, due to which the aircraft wing has a low aspect ratio and area. As a consequence, takeoff performance is reduced. \УΟ 98/30444 ΡСΤ/ΙШ97/00001

landing characteristics of the aircraft, compared with subsonic analogues. Since the number of runways suitable for aircraft operation decreases with the required runway length, and the travel time to the airport increases, the total time costs for the trip, even at supersonic flight speed, are reduced insignificantly.

In order to accommodate a relatively large amount of fuel, the fuselage has a greater length. As a result, its wetted surface and, consequently, its aerodynamic resistance and the weight of the structure increase. The trapezoid shape of the fuselage cross-section is uneven from the point of view of the structure’s operation on excess pressure inside the fuselage, which also increases the weight of its structure. This cross-section shape is also not optimal for providing high passenger comfort, since the maximum cabin width should be at elbow level, and not at floor level, as in the trunk type. The engine nacelles, spaced apart along the wing span, partially unload the wing, but increase the wave resistance by approximately 20% and the friction resistance of the engine nacelles by approximately 40%, which is associated with the shape of the nacelles themselves (the area of the midsection Mοτοndolla προροο by 1.5 times increases the area of inlet into the air intake) and the wetted Information about comparison with a combination of new engines in a single integrated engine nacelle. In addition, the use of spaced engine nacelles complicates the task of ensuring aircraft balancing in the event of failure of one of the engines.

POSSIBILITY OF IZOBΡΕΤΕΗIYA. The objective of this invention is to develop a supersonic command aircraft with an aerodynamic configuration that ensures a reduction in the weight of the aircraft structure, achieving high performance both in a cruiser plane and the possibility operation from airfields used for basing subsonic analogues. The technical result consists in reducing the wetted surface of the aircraft, reducing the wave resistance of the aircraft, and reducing the relative weight of the airframe.

The technical result is achieved by the fact that in a light-sound aircraft containing a fuselage, a wing with mechanization, a power \νθ 98/30444 ΡСΤЛШ97/00001

4

an installation consisting of two or more engines, chassis, vertical stabilizer, aerodynamic controls, control system, the fuselage of the aircraft is integrated with the wing, the shape of its midsection is close to circular, the engines are placed in a single engine nacelle integrated with the tail section of the fuselage, while the fuselage does not protrude beyond the engine nozzles, the air intakes are located under the wing and their front edges are located at a distance of 0.6...0.8 of the fuselage length, counting from its nose, the lower surface of the engine nacelle is made as close as possible to an equidistant surface in relation to the lower surface of the wing, and the lateral surfaces are practically parallel to the plane of symmetry of the aircraft, each half of the wing is made of three sections, and the values The relative vibrations of the central and intermediate sections of the fan at the fracture points are 0.2...0.35 and 0.6...0.75 Accordingly, the bend angles at the last joint, starting from the tip of the tail, are 70°-82° for the rear sections, 55°-65° for intermediate section and 35°-55° for the end section, the swept angles of the rear edges of the end and intermediate sections are close to zero (± 10°C), and the value of the wing root length is equal to 0.8...1.0 of the fuselage length.

It is possible to use engine air intakes with a fixed compression wedge angle when limiting the cruising flight speed to the number M = 1.8 (1900 km/h).

Thus, the specified result is achieved due to the integration of the main elements of the aircraft, their rational mutual arrangement, the use of a wing of complex shape in a plan with a certain ratio of parameters.

SKETCH WRITING. Fig. 1 shows the general view of the supersonic aircraft in three projections. Fig. 2 shows the diagram of the aircraft wing.

THE BEST VARIET OF EXISTING SELECTION. The aircraft (see Fig. 1) contains a fuselage 1, a wing 2 with mechanization, a nacelle 3 combined for two or more engines, integrated with the tail section of the fuselage, chassis 4, vertical stabilizer 5, aerodynamic controls 6 and a control system. \νθ 98/30444 ΡСΤ/ΙШ97/00001

The fuselage of the aircraft is integrated with the wing, the shape of its midsection is close to circular. The engines are located in a single nacelle, integrated with the tail section of the fuselage, while the fuselage does not protrude beyond the engine nozzles. The air intakes are located under the wing and their front edges (depending on the use of adjustable or non-adjustable air intake compression wedges) are located at a distance of 0.6...0.8 of the fuselage length, counting from its nose. The lower surface of the engine nacelle is practically equidistant from the lower surface of the wing, and the lateral surfaces are parallel to the plane of symmetry of the aircraft. As a result, the fuselage length is reduced by 1.5...2.0 times, the maximum cross-sectional area taking into account the engine nacelles (midsection of the aircraft) is reduced by more than 1.5 times. This allows to reduce the value of frontal resistance and the weight of the structure. Reducing the resistance and weight of the structure, in turn, allows the use of lower-thrust engines with smaller weight and dimensions and lower fuel consumption.

To compensate for the loss of fuselage volume required to accommodate fuel, to maintain high load-bearing properties at both supersonic and subsonic flight speeds, to minimize the washed surface and to reduce the weight of the structure, each half The aircraft wing has three sections: root, intermediate and tip.

The root section (see Fig. 2) is made with a large swept angle along the front section (70°-82°), has a relative span of 0.2...0.35 of the wing half-span, while the length of the wing root section is equal to or several times shorter than the fuselage length along the plane. aircraft symmetry. As a result, the height of the wing increases, which allows for an increase in the volume for fuel placement, the implementation of the "super-sound rule of areas", and a reduction in the weight of the power set. When the sweep angle increases to more than 82° and the relative span decreases to less than 0.2, the root section degenerates. At a wing angle of less than 70° and a relative span of more than 0.35, the effect of increasing the structural height and reducing the wave resistance becomes smaller than the loss from increasing the wing area. The root section ends with a control organ. \νθ 98/30444 ΡСΤ/ΙШ97/00001

6

The intermediate section is made with a forward edge sagittarius angle of 55°-65°, which is optimal for supersonic flight. The rear edge sagittarius angle is close to zero (± 10°C), which ensures effective operation of the controls. The front and rear flanges of the intermediate section are joined to the front and rear flanges of the wing root section without gaps.

The end section of the semi-wing is relatively small in area, the parameters of the cathode have little effect on the weight characteristics of the wing and the aerodynamic characteristics of the flight modes with supersonic speed, but have a significant effect on aerodynamic characteristics at subsonic speeds, including takeoff and landing modes, are made with a sagittal angle at the front edge of 35°-55° and start with a relative span of 0.6...0.75. At a wing angle of less than 35°, the stability and controllability characteristics at high angles of attack (in takeoff and landing modes) are deteriorated. At a span greater than 0.75, the effect from the tip section becomes insignificant. The wing aspect ratio is close to zero (± 10°C). The front and rear wing edges of the end section are joined respectively with the front and rear wing edges of the intermediate section without a break. The wing aspect ratio is 1.4...2.0.

To reduce the weight of the engine nacelle, simplify its control system, use lighter and cheaper structural materials, and simplify the air conditioning system, it is possible to use an air intake with a fixed compression wedge angle. The face speed of the flight will be limited by the number Μ = 1.8 (1900 km/h). In this case, sufficiently high coefficients of restoration of full pressure in the air intake are ensured, the temperature of the aircraft skin is reduced to a value of less than 90C, which makes it possible to reduce the length of the air intake with the air duct by almost 20%. In this case, the increase in flight time will not exceed 10%.

To improve the speed of the aircraft and the movement of the aircraft in aerodynamic direction, it is possible to use additional engine air intakes above the fuselage sides. 98/30444 RСΤ/ЙШ97/00001

7

The remaining items, units and systems are made on the basis of known principles and methods of design.

In order to confirm the feasibility of implementation and evaluate the effectiveness of the developed aircraft system according to the proposed invention, tests were carried out on a variant of an administrative aircraft designed to carry 6 passengers with a high level of comfort. distance of 6000 km with a supersonic flight speed corresponding to the number M=1.8, when using airfields with a runway length of no more than 1800 m for takeoff and landing. The results of the work and calculations show that the aircraft has the following geometric Patterns: length - 22 m, body span - 12 m, angles of stellation at the front end are . The relative span of the root and central sections of the wing in fractions of the half-span of the wing at the break point are, respectively, and the aspect ratio of the wing is equal to 1.55. Due to the short flight time - about 4 hours, the cross-sectional dimensions of the passenger cabin are reduced to a maximum height of about 1.5 m and a maximum width of about 1.5 m, which allows to significantly reduce the aerodynamic drag of the aircraft and the weight of its structure. The air intakes of this variant are made with non-adjustable compression wedges, due to which their length and, consequently, the weight of the structure are reduced, and the value of the cruising speed of the flight is limited by a value corresponding to the number M = 1.8.

The specified scheme ensures maximum aerodynamic quality at supersonic speed at a level of , and the relative weight of the glider is at a level of 19...20% of the takeoff weight. As a result, with a crew, six passengers and baggage on board, the aircraft provides a flight range of more than 6,300 km with a takeoff weight of less than 24 tons. The required length of the runway is 1800 m. According to calculations, the cost of operating such an aircraft is at the level of subsonic analogues.

Claims

\νθ 98/30444 ΡСΤ/ΙШ97/00001 8 ΦΟΡΜULΑ IZΟBΡΕΤΕΗIYA. 1. A supersonic aircraft comprising a fuselage, a wing with mechanization, a power plant consisting of two or more engines, chassis, vertical stabilizer, aerodynamic controls, a system 5 control, characterized in that the fuselage of the aircraft is integrated with the wing, the shape of its midsection is close to circular, the engines are located in a single engine nacelle integrated with the tail section of the fuselage, while the fuselage does not protrude beyond the engine nozzles, The air intakes are located under the wing and their front edges are located at a distance of 0.6...0.8 of the fuselage length, counting from its nose, the lower surface of the engine nacelle is practically equidistant from the lower surface of the wing, and the side The surfaces are made parallel to the planes of symmetry of the aircraft, each half of the wing is made of three sections, and the values of the relative dimensions of the root and intermediate sections 15 wing in the lobes of the half-span of the wing at the break point are 0.2...0.35 and 0.6...0.75 respectively, the blade angles along the front edge, starting from the nose of the wing, are 70°-82° for the root section, 55°-65° for the intermediate section and 35°-55° for the end section, the arrowheads of the rear edges of the end and root sections are close to zero, and the value of the root 20 wing length is equal to 0.8...1.0 fuselage length. 2. A supersonic aircraft according to paragraph 1, characterized in that the engine air intakes are made with a fixed compression wedge angle.