On 28 January 2017, the Russian government announced as a result of the investigation into Progress MS-04 the recall of all Proton-M 2nd and 3rd stage engines produced by the Voronezh Mechanical Plant (common to the failed Progress flight) including the disassembly of three completed Proton rockets and a three and a half month suspension of flights. An investigation had found that engine parts that were supposed to use precious metals had been substituted for cheaper alternatives that were unable to resist high temperatures as well as finding that production and certification documentation were falsified.
