Super-fast helicopters - projects and realities

Many readers must have watched the sci-fi movie 6 Days, where, after taking off from the ground, Wishpercraft helicopters fly through the sky like jet planes. It is precisely this idea that Russian aircraft designers from the Kamov Design Bureau want to implement. Ka-90 (in some sources, Ka-100) is a vertical take-off aircraft capable of gaining 450 km/h first, and then folding its blades into a "case" and turning on the "afterburner" to take off at a speed of 800 km/h.

Concept

The film is a film, but the design bureau team was inspired by something else, and not just Hollywood fantasies: in 2008, at the HeliRush exhibition, the first mock-up of the prototype was presented by representatives of the design bureau. Kamov was demonstrated to the general public. The concept is completely new and involves lifting off the ground with the help of short propeller blades, which then accelerate the device to 450 km / h. Then they "turn" into a swept wing. Next, a bypass turbojet engine is turned on, through which the device picks up speed of 700-800 km / h. In this case, the screws are completely removed into the case at the top of the helicopter. When landing, the sustainer engine is turned off, the blades are “pulled out” and the machine descends to the ground like a conventional helicopter. No one else in the world, including the United States, has such a concept yet.

It is assumed that in the future the new machine will replace the Mi-8 and will be able to take on board up to 24 people. The weight of the device, which is controlled by two pilots, will be from 10,5 to 11,5 tons. The main rotor diameter is 8 m. First, the army will receive the helicopter, then a civilian version will be created.





There are other questions, such as "What is such an aircraft for?". It is possible that the answer will have to be sought in the relatively recent American developments of such machines. Below is an overview of one of the most promising.

Sikorsky S-97 Raider

This is also a high-speed rotorcraft, though with much more modest limit values, when compared with the Russian project. However, while in the Russian Federation this is only a plan so far, the Americans have already tested a real helicopter. Its assembly began in 2012. Initially, it was clear that the car was being made for the army, as evidenced by its name, translated as "scout". The novelty is designed to replace the Bell OH-58 Kiowa Warrio model, which was used in the Vietnam War.



The helicopter was developed on the basis of the Sikorsky X2, a concept shown to the public earlier. This machine took to the air 23 times and reached a speed of 460 km / h. In 2011, the program was closed, and the results obtained were decided to be used in the development of the S-97.



By creating a new car, the Americans essentially tried to design a "flying infantry fighting vehicle" with high maneuverability and speed. The helicopter is armed and can transport up to 6 reconnaissance paratroopers. Some technical characteristics of the machine, which was tested on 25.06.2019/2015/2017 in Florida at the West Palm Beach airfield (the first flight took place in XNUMX, in XNUMX it was unsuccessful - there was a hard landing):

✅ engines and their power - General Electric YT706, 2600 "horses"
✅ screw diameters - 10 m (carrying), 2,1 m (pushing)
✅ takeoff weight - 4,057 tons (normal) and 9,99 tons (largest)
✅ speed - up to 444 km / h, with full armament 407 km / h
✅ ceiling - 3048 m
✅ range - 1140 km

To date, nothing is known about the high-speed helicopter, there is information that it was supposed to take part in the US Armed Forces tender for the creation of an attack and reconnaissance helicopter. But, obviously, something did not satisfy the military. What can Russia say about this?

Ka-92

It uses the same technical solution as that of the Sikorsky company. The Ka-92 has short and stiffer hingeless blades equipped with specially shaped tips. The aircraft is propelled forward by a pusher propeller located at the rear of the machine. It is rotated by a reduction system powered by a single engine.



The chassis was made retractable. The designers assume that the following technical parameters have been achieved:

✅ engine - VK-3000 turbocharged units with a capacity of 3200 "horses" (VK-2500 will be supplied at the initial stage):
✅ speed - up to 430 km / h
✅ maximum takeoff weight - 16 thousand kg
✅ range - 1400 km
✅ number of passengers - up to 30 people

The helicopter is supposed to be produced in several versions - military, rescue, passenger and medical. A total of about 92 billion rubles was allocated for the development of the Ka-7,5. But something is not seen and nothing is heard about the fate of the helicopter, or at least progress in creating a flying prototype.

Other projects

Of the Russian options, this is an attempt by the Design Bureau. Mile in the form of the creation of the Mi-X1 concept, developed according to a single-axis scheme. However, today there are no real results on the new helicopter. Instead, they demonstrated a "modernized" Mi-24 with a new cabin and other blades (later they were put on the Mi-28). As for the latter, we can say for sure - they turned out. Thanks to them, a decent speed of 380 km / h was achieved. But on this, things went smoothly and died out: the new blades turned out to be expensive! By the way, the Americans are doing no better. The X-49A Speedhawk, assembled according to the single-axle scheme, unlike the Mi-X1, managed to fly back in 2007.



Attempts to improve it only convinced that for helicopters with this type of blades 400 km / h is the physical speed limit. The installation of a main rotor and even small wings did not help to overcome this maximum.

"Civilian" conclusions

The question involuntarily arises: is a high-speed helicopter for “peaceful” aviation needed? Alexander Braverman, who works in the Design Bureau. Mile made calculations that showed that the best economic parameters for rotorcraft correspond to a speed of 300-310 km / h. its increase will cause unnecessary fuel costs, increased noise, vibration.



Any real plane, the same An-24, flying at a speed of 550 km/h unattainable today for helicopters, will land on a dirt strip without any problems and take off. But it costs, as well as its operation, several times less than a super-fast helicopter.

What about the military?

It seems that such a machine is in demand by them, at least the US Department of Defense (and ours too) was interested in such projects. But here it has its own “hook”: for an aircraft, its invisibility is of key importance: the lower, the better and more reliably you can bypass the enemy’s air defense. But this is a height of 5-15 m, suggesting a speed of 80-100 km / h. Flying at such a distance from the ground when the “speedometer” is 400-500 km / h is pure suicide. In conclusion, it is worth recalling the conclusions of the aforementioned academician Braverman about attempts to build an ultra-fast helicopter - “increasing speed will require increasing the mass” of a rotorcraft. What convinces: it is unlikely that in the near future we will hear something about new ultra-high-speed helicopters.