Piasecki X-49A Speedhawk Helicopter Military Specifications – this is an experimental American machine, which is considered a helicopter, but it contains elements of a helicopter, and an already seemingly forgotten flying machine – gyroplane.
Piasecki X-49A Speedhawk Helicopter Military Specifications
|Development Status||Phase 1 complete|
|Manufacturer||Sikorsky, Piasecki Aircraft|
|Engine||Two General Electric T700-GE-401C turboshaft engines (1,620 hp (1,210 kW) each) (1,210 kW) each. (1,210 kW) each|
MilitaryEzyInfo.com – It is worth noting that this type of aircraft has already been practically written off in serious aviation. However, if the project X-49A Speedhawk still ends in mass production, this kind of aircraft will be able to get a new breath, and with the success of the model can count on taking its place under the sun. The same place that was once secured by traditional helicopters.
First of all, it is worth reminding the reader what a gyroplane is. These aircraft have a propeller (HP) to create lift, but their propeller rotates in autorotation mode under the influence of aerodynamic forces.
The gyroplane propeller has a simplified design, it has no automatic tilt, and during the flight, it tilts back, against the airflow – similar to an airplane wing with a positive angle of attack. At the same time, helicopters tilt their main rotor in the direction of movement.
In addition, a gyroplane is usually also equipped with a pushing or pulling propeller, just like traditional airplanes, which belong to piston aviation. It is with this propeller that the gyroplane achieves its horizontal speed.
In addition, gyroplanes differ from rotorcraft, which have a permanent propeller drive from the engine, which allows them to apply both the helicopter flight mode and the autorotation mode.
At high flight speeds, their rotor system functions similarly to gyroplanes (autorotation pitch mode is used), providing the aircraft only with lifting power, but not thrust. It can be said that rotorcrafts have taken an intermediate position, combining the qualities of helicopters and gyroplanes.
But back to our “Speed Hawk”. In Russian, the name of the company that developed this experimental vehicle sounds like Pyasetski. The predecessor of the modern X-49A Speedhawk was the Pathfinder, which Piasecki began to design in 1960.
It was this machine that first brought the designers back to the forgotten gyroplane. The Pathfinder made its first flight on February 21, 1961, less than a year later the helicopter was equipped with a wing as originally planned, and the tail rotor was replaced with a three-bladed push-pull cowl with control surfaces at the exit.
The latter condition provided the machine with track control and parried torque. During flight tests of the built specimen, it was possible to achieve a cruising speed of 273 km/h. After this success, the U.S. Defense Department became involved in financing the project, setting a condition for achieving a speed of 370 km/h.
Following military requests some modifications were made to the Pathfinder helicopter design, particularly increasing payload, lengthening fuselage, increasing re-motorization, replacing thrust and main rotor.
After that, the helicopter was designated as 16H-1A or Pathfinder II. Significant acceleration of the air vehicle was achieved by redistribution of input power from the main rotor to the pusher propeller.
In this mode, the main lifting force of the Pathfinder II was created by means of the wing. The results of these tests were more than encouraging – the helicopter could reach a speed of 361 km/h, the vehicle was distinguished by good maneuverability and controllability both at low and high flight speeds.
Flight tests of Pathfinder II started on September 21, 1967, and in early 1968, the US Army placed an order for 375 such machines. The built aircraft could reach a speed of 407 km/h and carry a considerable payload.
However, due to numerous technical problems and after a series of accidents that occurred with prototypes of the machine, plans for series production of Pathfinder II attack helicopter were curtailed, and work on the project was completely stopped in 1972. Piasecki conducted theoretical work on the helicopter of this scheme until 1978, after which it stopped them due to lack of funding.
However, Piasecki’s achievements were not completely forgotten, in the 1990s the military remembered them again. It was at this time that the U.S. Army showed interest in improving the performance of combat helicopters AH-1W SuperCobra and AH-64 Apache.
As a result, a serious amount of work was done, which included a cycle of ground tests and full-scale simulations. The military needed new control systems, changes to the powertrain, etc.
As a result, the U.S. Defense Department made an order to modify the medium multi-role helicopter UH-60 Black Hawk. After about 3 years of work on the project, he received a new name and index – X-49A Speedhawk.
The fundamental difference between this project from the old 16H-1 was a different design used to deflect the propeller airflow – was used more efficiently, a composite hemisphere, which can rotate 90 degrees at low speeds and hovering, and at high-speed horizontal flight, it fit into the contour of the shell. Thanks to this it was possible to get rid of the source of vibration in the tail boom and reduce loads. Its first flight X-49A performed on June 29, 2007.
As a result of a series of tests, the new X-49A SpeedHawk has shown a 47 percent increase in speed with the same performance as the basic SH-60F helicopter, in addition, the machine has demonstrated a twofold reduction in the level of vibration.
The SpeedHawk’s performance has been improved with a Vectored Thrust Ducted Propeller (VTDP) located in the tail rotor tube, and the use of wings to reduce rotor loading and increase lift. Piasecki’s immediate plans include installing retractable landing gear and a cowling on the main rotor hub to further reduce vibration levels, as well as installing the third engine on the X-49A.
The manufacturer plans to bring the cruising speed of the serial machine to 383 km/h and the maximum flight speed to 415 km/h. At the same time, the production multipurpose SH-60F helicopter can reach a maximum speed of 256 km/h.
The unladen weight of X-49A will increase by 700 kg, primarily due to the installation of a third engine. At the same time, the range of the helicopter should grow almost 3 times, and the payload will increase by 230 kg.
After finishing the first stage of tests, Piasecki Aircraft received funds to carry out the finalization and the second stage of flight tests of its experimental helicopter. According to Aviation Week, so far the Pentagon and U.S. Congress have agreed to fund the program at $7.8 million.
Separately, we should note the fact that after the end of Phase 1 flight tests X-49A SpeedHawk its further prospects remain unclear. According to Piasecki Aircraft representatives, the financing isn’t enough for full implementation of the project and should be increased. At the same time, the company stated about the positive signals it receives from the U.S. military.