... So, back in 2010, it became clear that a few poorly designed plane. Required operating overload withstand could not cut the rivets on the air intakes, air-to-air heat exchangers for cracked welds, and the fuel in the tank №3 categorically refused consumed completely. To the first safety car came the assigned resource to 300 hours, in August 2011, it delivered on completion (the rest of the gain made in the factory), and started to design the machine of the 2nd stage (by the way, incidentally removed from the keel 50-1 left there wrench key). At the 2nd stage significantly increased the proportion of composites (virtually the entire lining of the RMB has become), but the weight of the airframe due to increased KCC still excessively increased. Then they decided to replace many nodes B95 duralumin and AK-5 on the aluminum-lithium alloy 1461T with a specific weight of almost 20% less. In October 2012, the final decision on the launch of the 2nd stage of production. It was planned 2 cars - T-50-7 and T-50-8. At that time, at different stages of production are 3 cars 1st stage - 4, 5, 6. But just woke up and decided to make a 50-7 statics. And in February, the 13th decided to make the transition model and assign the T-50-6. To avoid confusion, the T-50-6 of the first phase became known as T-6.1.50, and the second phase of the machine - T 2.6.50.
But among the imported parts to the T-50 were American cellular structure of carbon fiber, widely used in the wing and tail. Our military leadership decided that this is unacceptable and has decided to "importozamestit" and instructed CVTs "Technology" from Obninsk develop domestic cellular materials. By the way, all the other composites for the T-50 is also made in Obninsk. Expectedly, obnintsev provaflili all time. As a result, grief Sagittarius (he is now GK Pak, not Davydenko) in May even suggested removal of plumage from T-50-4 and put on 6-2, modified fairing and drive spindles, but a month ago finally came honeycomb.
Another problematic issue was the alloy 1461. Desperate crackled when mechanical working, then there must be said that the assembly we still conducted on technologies 70s, that is, the assembly units in unit kuvaldometr still very popular. A similar treatment alloy does not bore. As a result, it went reconversion of the parts of the 1461 B-95, and sometimes back again in 1461.Chto, of course, led to the indescribable delight everyone, especially prochnistov.
Thus passed in 2013, 2014 and in February 2015 of the fuselage was docked 6-2 ...