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Vezano za M-50 Mjasiščev:
A bit on story of it's development. Compiled this article a while ago, because this machine interested me a big deal.
Soviet air force command did issue a very strict demands for a new bomber - should have been able to stay at supersonic speed for most of its flight, range 15000 km, to carry at least 1 5000 kg bomb, and that on the background, that they stood to death, but refused to lift safety requirements: armoured cockpits, protected self-sealing fuel tanks, at least 3 defensive turrets. There were some studies of partially reusable and partially disposable systems, like in case of american B-58 "Hustler" research. I will not go too much in the details, just mention, that these designs included such systems, where engines were disposable and combined with fuel tanks, a system of two airplanes joined the way, that main body was acting like a giant fuel tank with wings and engines and was wholly disposable in flight, while bomber itself with weapons and fuel was attached to its nose, so that its wings acted as a "canard" horizontal stabilizer and even a system with remotely controlled plane towing bomber with supersonic speed , than when it used all of its fuel, it was disposed of and bomber wont on on its own. In the end, Russians decided, that bomber must remain one whole.
New machine design was optimized for maximum possible efficiency, fuel made up to 70% of its takeoff mass, but calculations (it was a first airplane, to be designed using complex calculation and modelling by computer. That time's computers of course) still, however showed, that by 1958 (as authorities have demanded) to build such a plane with technologies of that time was just impossible, so air force command loosened its requirements, allowing "range not less than 12 000 km with 2 aerial refuels". Planned were to use either four "NK-6" Kuznetsov Turbofans, or or four Dobrynin WD-9 Turbojets. Research showed, that high temperature turbojet would be more efficient, thus Kuznetsov turbofans were excluded from project. However later on, a new engine was viewed as possible powerplkant - Zubets M16-17. These engines promised to offer an excellent performance, however yet only on papers. By 1955, both Dobrynin and Zubets only managed to conclude pre-dev projects and lack of existing engine began to slow down aircraft fuselage design, which went in a good tempo so far.
Until 1955 design went on rapidly, by december wer ready pre-prototype design drafts, but designers and air force command remained in concern - calculations still showed, range was still not enough. Designers wrote in project, that with given technologies of that time it is impossible to get needed requirements fulfilled before CAGI (Central Aerodynamics and Hydrodynamics research Institute) finds a way, how to increase projected construction aerodynamic quality by 0.2, points (would give 400 km range increase) chemists invent a new fuel with better heat emission +350 km) and technologists and experts in durability lighten the construction by using aluminium-beryllium alloys and clarification of needed durability standards by 3-4 tons (+400 km) and new avionics, with increased amount of semiconductor diode and transistor based components instead of lamp-based ones (these technologies were indeed under development in USSR back then). This would have ensured, the required range would be achieved. If not, last argument would have been return to idea of disposable engines, increase amount of fuel and improvement of wing's aerodynamic qualities by controlling the boundary layer (it would give another 900 km range increase,however technically too complicated and expen$ive).
Such document was given to the air industry ministry of USSR on april6th 1956 and given to air force command to review.
Air force command made their own research and concluded, that in present state, project is "unacceptable and must be improved further to meet the requirements from July 19th of 1955". as Air Force Command concluded in its own research, submitted project was able only to achieve 9200-9600 km range without refuelling and 12000-12500 km with two aerial refuelling, thus lacking another 2000 km of range from what claimed the designers. Air force comand also consistently insisted on full implementation of required safety measures (3 turrets, armour, protected tanks), without any compromise. They also claimed, that it would require 6000 m runways (twice as much as requirements stated) without rocket boosters.
Designers pushed as hard as they could, reworked control systems, engine control, landing gear, but their abilities, even perspective ones were literally squeezed out and exhausted with that time's technologies even those, that were under development. Air force again sayed, that in current condition project is "unacceptable". Protocol was signed on September 19th 1956, claiming industry is responsible.
However Minister of aeronautic industry then answered, that Air force command issues a too high requirements, excessive for what they want to do. He did not want to accept rejection of this project, as building a supersonic strategic bomber is a hard and unusual task and parts of it require months and years to work out and develop. As current research has showed, it was simply impossible to give air force what they want in given time.
After heated debates, the decision was revised and compromise was accepted - air force will get what they want later, than they expect, but Myasischev berau will build a first "technology demonstrator prototype" with performance, promised by designers, to begin flight testing of fuselage and main systems. And then later build second prototype, that will indeed fulfill all the requirements.
So what conclusions may be made?
Really existed M-50 was not and could not have been a real strategic bomber. From the beginning this exemplar was built as it would be called these days as "technology demonstrator" or "experimental aircraft". to work on systems and components of future real strategic bomber.
Important evidence to this is its powerplant. As we remember, a bomber must have installed WD-9 or M-16-17, both had 18 000 + kg thrust. But it was clear, that htese engines will not be ready in 1958, thus tests were conducted with WD-7M engines, 14500 kg thrust each, It gave the possibility to test-fly the fuselage on all main work modes. However, when after on March 2nd 1956 began projection works for M-50 with WD-7M engines, it became clear, that these engines as well will not be awailable in time.. Situation was desperate, Myasischev then decides to install a previous model engines, WD-7A, only 11000 kg thrust each, which is 40% less than needed for proper testing and only 60% of what a full version bomber would have had. As calculations showed, WD-7A were even insufficient to break sound barrier, but there was no other way - most essential was to push the machine at least in some way into air and begin testing.
Trying to solve all the eerged issues, flight testing began 1.5 years later than they should have, in summer 1959. From November 27th 1959 to October 5th 1960 M-50A(thiswas designation of tech demonstrator) made 11 test flights, having 8 and a half of hours of flight time. on September 16th 1960 M-50A achieved its highest achieved speed of 1090 km/h, powered still by WD-7A. Myasischev designers claimed, it achieved mach 1.01, Gromov's test flight center claimed it got only mach 0.99, who is right isunknown to these days.
By april 1961, special engine WD-7MA was constructed and supplemented 2 of prototype's engines. Engine differed from base model WD-7M by improved afterburner. With these engines, Myasischev hoped to achieve mach 1.35, but since then only 8 more flights were conducted including that last pass on parade, thus 19 test flights were made in total.
So why was this project discontinued? Clearly not because of poor design, designers squeezed out evry tiny bit of speed and range from technologies of that time, and even not because of engines, sooner or later they would have been ready.
It was a fatal conflux of an amazing industrial might of soviet military industry and its absolute defencelessness before party and governmental system. Huge labs, best scientists and engineers, along with chief designers, precise calculations and justification of economical and military need for such high-tech machines faded when compared to "opinion, that was developed in Central Comitee".
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