Instead of the F-35B: is it too early for the sixth generation
Yes, no matter how strange it may seem, a revised concept of the VTOL aircraft has been approved as part of the X-Plane special operations program.
It would seem: the F-35B has just entered production, and not everyone who wants it has received it. And now - a new concept, new plans. And the plans are quite aggressive: for starters, a high-speed special-purpose transport aircraft capable of operating outside equipped runways... without a crew!
And then... anything can happen.
A very unique and interesting company, Aurora Flight Sciences, got involved.
Well, Aurora Flight Sciences recently unveiled an updated design of an aircraft with a propeller in the wing and a vertical take-off and landing capability, which it is developing in conjunction with the US Defense Advanced Research Projects Agency (DARPA).
The key target of the new concept is the Aurora unmanned demonstrator, which was developed under DARPA Speed and Runway Independent Technologies (SPRINT). The company was one of four selected to participate in the initial development phase of the SPRINT concept, the others being Bell, Northrop Grumman and Piasecki Aircraft.
Aurora Flight Sciences has already moved into the second phase of the project, which will include preliminary theoretical testing of the project's developments. It is unclear whether any other companies involved in the project have moved forward.
Rendering of Aurora Flight Sciences' revised SPRINT design concept
DARPA says the primary goal of SPRINT is to demonstrate a "transformational combination of aircraft speed and runway independence," which includes "the ability to cruise at 700 to 800 km/h at appropriate altitudes and take off from unprepared surfaces." The program is directly related to the US Special Operations Command (SOCOM) High Speed Vertical Takeoff and Landing (HSVTOL) project.
In addition to vertical takeoff and landing, the aircraft is capable of short takeoff and vertical landing (STOVL), ultra-short takeoff and landing (SSTOL), and conventional takeoff and landing.
The company's press release also highlights the presence of three elevator propellers, extensive use of composite materials and a "uncrewed cockpit."
The design that Aurora revealed last year had four propellers and a traditional cockpit area with two air intakes just behind it on the top of the fuselage.
Rendering of the original Aurora SPRINT concept
The revised design features three lift rotors arranged in a triangular pattern, one at the nose and two on either side of the center section. There are also two large, angular air intakes under the nose rather than at the top of the fuselage, as well as what appears to be a central exhaust located at the rear between the aircraft's v-tail.
An animated render released by Aurora shows a flat panel sliding across the top of the front lift fan and round hatch covers covering the propellers for level flight. There also appears to be compartments in the lower fuselage. At the top of the central fuselage compartment are two additional auxiliary planes that can vent air away from the main propulsion system while the structure is in VTOL mode.
Aurora Flight Sciences created a demo video showing the prototype systems in action. For certain reasons we can't show it here, but the four main positions look like this:
It has already been noted that there are very close similarities between the Aurora's propeller-in-wing configuration and Ryan Vertifan's design from the 1960s. This comparison highlights that propeller-in-wing design concepts, as well as those that use lift fans elsewhere on the aircraft, are not new at all.
Two Ryan XV-5A Vertifan prototypes. On airplanes, the lift fan covers in the nose are open, while the covers over the lift propellers in the wings are closed. Ryan Aeronautical from the SDASM archives
XV-5A Vertifan in vertical takeoff and landing mode. Note the split round covers in the open position above the wing-mounted lift screws, similar to those seen in the new Aurora SPRINT renderings.
The projected size of the current Aurora SPRINT design concept and how much payload it could carry if the vehicle reaches flight status are not yet clear. But the concept of using all systems that provide takeoff and landing in unmanned mode is clear. Including vertical ones.
“FIW technology can be scaled to four or more lift rotors to meet future aircraft requirements, and this could open up opportunities for a future family of systems. Likewise, while an unmanned demonstrator offers benefits in testing and risk reduction, FIW technology can be fully transferred to traditional crewed aircraft."
– noted in the Aurora press release.
In general, the company demonstrates its focus on results, which will be the first successful flight of the prototype.
Whether this will happen remains to be seen. DARPA programs like the X-plane do not always achieve their goal of creating a flying demonstrator. Aurora has known this since developing the XV-24 LightningStrike for the agency in the 2010s. Despite successful flight testing and plans to launch a full-scale XV-24, DARPA canceled the program in 2018, citing, in part, a lack of a service partner within the U.S. military.
Video from Aurora
However, there is very clear interest in DARPA's SPRINT concept from SOCOM and by extension the Air Force Special Operations Command (AFSOC). A high-speed, runway-independent transport aircraft could provide additional operational flexibility and reduced vulnerability, especially in a potential future high-level conflict such as the one in the Pacific against China, specifically for special operations units.
The capabilities provided by SPRINT or another program based on technology developed within the program can be used not only within US special operations forces. The US military is increasingly concerned about the vulnerability of large bases, especially in the context of major combat operations in the Pacific region.
The U.S. Marine Corps is retooling its entire force structure to better conduct expeditionary and special operations, with a focus on rapidly establishing forward bases in remote and rugged areas. The Marine Corps is also the only branch troop in the US military, which operates a variant of the F-35B stealth fighter that is capable of short takeoff and vertical landing, thanks to a lifting rotor in the front of the fuselage and a steerable exhaust nozzle.
F-35
With all this in mind, recent years have seen a steadily growing interest among the US military branches in new and more adaptable to modern runway independent, crewed and uncrewed aircraft concepts, as well as related tactics, techniques and procedures for support a wide range of missions.
Overall, it will be very interesting to see how Aurora's rotor-in-wing concept for SPRINT continues to evolve in anticipation of future flight testing. The Americans generally paid a lot of attention to the capabilities of their MTRs, which gave rise to many very original devices. More than 142 years have passed from the XC-40 to the new creation Aurora. There is a certain continuity.
But there is an interesting point here: it was not for nothing that the F-35B flashed in the text, not at all in vain. Besides the Osprey, today it is the second VTOL aircraft in the American armies and navy. And such large-scale work on the new project suggests that the V-22 Osprey tiltrotor no longer meets the requirements of today.
An unmanned transporter with the ability to land and take off not where it can, but where it needs to – this is powerful. But here it is worth remembering that appetite usually comes with eating. In principle, it is not so far from a transport drone to an unmanned bomber. The only difference is in the method of delivery of the goods. So what is next…
And then we can expect prototypes of that sixth generation fighter. Unmanned, hypersonic in afterburner, capable of maneuvering at overloads exceeding the capabilities of the human body.
Everything is beautiful, we have already seen a lot of semi-fantastic stories on this topic. However, developments on the transport aircraft and bomber will provide a lot of important information that will ultimately help create a platform such as a sixth-generation fighter.
But for now, let's see how Aurora creates its miracle device. And then we will draw conclusions.
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