What more expensive helicopter: chetyrehdvigatelny or twin-engine?
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What more expensive helicopter: chetyrehdvigatelny or twin-engine?

What more expensive helicopter: chetyrehdvigatelny or twin-engine?

 

 

 "B-12 has surpassed everything that was created both before and after"

"... In favor of the transverse scheme, and the argument that it allowed to take as a basis for the project a ready-made propeller group of a heavy Mi-6 helicopter with two D-25V turbo engines and a five-bladed screw with a diameter of 35 m. This greatly accelerated the development. The effectiveness of the chosen solution is also indicated by the fact that as a result of the "doubling" of the power plant, the capacity of the B-12 has increased much more than twice, compared to the Mi-6 with its 12 of maximum load. True, for this I had to use the accelerated versions of the D-25VF engine with the increased 1000 hp. (Up to 6500 hp) power and lightweight composite blades (each blade has become lighter on 300 kg). However, a certain "gain" should also be attributed to the transverse arrangement of the screws.

 

For your information:

Experience of In-12 useful in the development of the Mi-26 - the largest and serial lifting helicopter in the world. Its presence in the production line is rightly proud of holding "Russian Helicopters", which collaborates with businesses VTB Bank ".

It is doubtful that developments in B-12 «useful» for Mi-26, because this helicopter - this is the height of perfection of the classical scheme. Only now pride on this occasion is not particularly: novelty for novelty at the expense of the future profitability of the vessel.

 The trouble is that our huge country with harsh climatic conditions is constantly in need of heavy helicopters, and the Mi-26 in the operation of exorbitantly expensive and today - just ruinous!

But back to the In-12, which is built, so to speak, two Mi-6, and the price of the Mi-6 less than the cost of the Mi-26 in 4raza! Hence the price of the helicopter in-12 twice as expensive as the Mi-6 or two times cheaper than the Mi-26.

What more expensive helicopter: chetyrehdvigatelny or twin-engine?

 

Later expected upgrade in-12 with two engines:

"Initially it was planned to build in-16 for three-screw scheme with six engines D-25VF, but then came the draft dray transverse circuit equipped with two powerful turbine engines with free low-speed turbines and vertical shafts.

 On the basis of this project in 1966, the “Milots” developed the variant B-12 under the designation Mi-12М. It was intended to replace the B-12 with four D-25WF engines with two newest D-30В engines with HP 20.000 power. design OKB P.A. Soloviev and increase the number of blades on each rotor to six. The Mi-12M was supposed to carry cargo of mass 25 t at a distance of 500 km, and mass 40 t - at a distance of 200 km. The proposal received government support, but due to the termination of the B-12 program, the development of the Mi-12M was interrupted at the stage of building a full-scale mock-up. ”

We assume that in-12M by modernizing the cost would be on par with the Mi-26, but at the expense of more powerful engines, and caught up to speed characteristics (difference-in 15k / h). And here it is appropriate to recall one of the routes for the development of the Arctic: a / p Tiksi - about. Boiler (540km) everything for the town.

What more expensive helicopter: chetyrehdvigatelny or twin-3?

 

In the distance 500km. Mi-26 15t transports cargo and in-12M ... 25t, ie on 2 / 3 more cargo for the same money.

Difference is impressive and it is doubtful that even then was the need for technical perfection outdated classical scheme of Mi-26 when the helicopter project in-12M compared to him initially showed a clear economic benefit, and whether it was necessary to spend huge money on the Mi-26 project when much cheaper would cost the modernization of already flying Mi-12.

Today the most advertised helicopter in our country is Mi-8, launched in a series of half a century ago. It seems to rejoice at this longevity, but it is artful and if the designers of the MVZ are patriotic citizens of Russia, few of us today would have ever remembered this "outstanding" helicopter, and its place in aviation from the beginning of 80-ies would have been occupied by a more advanced Mi -38 (20% less drag) with modern at that time engines TV3-117. Today his resource would have come to an end, and in the town on about. Boiler along with super-heavy Mi-12M flights would carry out the rotary-wing rotors of the same Mi-38, taking into account the experience of both Mi-12 and Ka-22, the weight niche of which is free after Mi-6 helicopter today. But the advantages of this rotary wing are not in the niche, but in its cheapness in comparison with the classical scheme: if the record speed Mi-38 = 320k / h, then for the rotorcraft this speed will be private - cruising, and the maximum load of two Mi-38 would be its usual Loading at normal flight weight. The smaller weight of the structure (in favor of a useful load) is due to the fact that the rotorcraft lacks heavy tail with end beams and intermediate gears in them. Hence the cost of the rotorcraft would be much lower than the cost of two Mi-38. In addition, the rotorcraft is convenient for loading and unloading - the tail screw does not interfere!

For safety:

 

What more expensive helicopter: chetyrehdvigatelny or twin-engine?

Even at the time of take-off from the Mi-26 the impression that the tail rotor is about to touch the ground, and then - trouble! At speed braking before landing tail rotor necessarily falls even lower!

 

But the designers of the cost center "teeth" clung to long-outlived classical scheme despite the fact that they have experience in In-12, the profitability of which their founder and teacher Mil proved at the beginning of the second half of the last century.

One of the memories on the Mi-12 pilot - test.

 “The flights showed very good handling and stability of the B-12. Pilot V.P. Koloshenko, who was piloting it, said that the helicopter flew steadily with an abandoned control stick for three to seven minutes. He also remembered the sensations unusual for the helicopter pilot: there were no blades flashing before the eyes of the propeller, vibrations and noise:

 "I seemed to be floating on a huge ship."

With confidence we can say that for passengers comfortable helicopter transverse circuit today NO! Either there is no helicopter airborne turbulence, but there are unpleasant shaking of the rotor and increased noise from the engine and main gearbox, which are located on top of the fuselage. In this cross-scheme helicopter shaking neutralized wings. Motor with gear from the fuselage far, so comfort flight on this machine is incomparably higher than a helicopter with a tail rotor not only the crew, but especially for passengers.

It is known that helicopters such as the passenger transport are not engaged, but they often have to transport so-called "Service" passengers on the rig, and the like, or to carry passengers, where other vehicles can not, for example, Naryan-Mar - about. Kolguev passengers and helicopters also worthy of a comfortable flight! And do not reveal the secret that 4-x motor rotorcraft reliable 2-x motor, and these are the need for operations in the Arctic and the Arctic!

And further.

What more expensive helicopter: chetyrehdvigatelny or twin-engine?

The photo clearly visible: to what are clumsy on the fuselage of the Mi-8 secured one additional tank barrel-shaped.

In rotorcraft main fuel tanks are located in the wings and aerodynamic suspended - on the pylons under the wings.

 

Vitalii Belyaev

A lot of letters, but the author has not revealed why necessarily need to break the forehead in a closed door and use wagon-a-la Chinook.

read the end of the article - stupid

We have a much better project "a la Chinook": Ka-102, but like the rest of Kamov's projects, the road is blocked by the liberal government of D. Medvedev - the project is not funded.

Good article!
but in Russia everything is not as it should be ....
so and we live
V12-worthy device
It shows once again that, in the Soviet Union have been developments
and that nothing good in modern Russia do nemogut
and there is nobody
there is no technical basis
and most importantly staff
a vast country occupied only by the construction of apartments and shopping centers ....

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