Russia has decided to ground all its Proton-M rockets for three and a half months because of flaws in the engines.

Progress MS-04 Space Cargo Crash

The announcement followed the crash of the Progress MS-04 space cargo late last year that destroyed one of the rockets just minutes after liftoff.

In December, the unmanned Soyuz-U vehicle with the cargo spacecraft bound to deliver supplies for the International Space Station broke up in the atmosphere over Siberia just six minutes after it launched from the BAIKONUR Space Center. The incident destroyed 2.6 tons of food, fuel, and other supplies.

Components Of Proton-M Rocket May Have Been Switched

Investigators blamed the incident on faulty engine parts. A report indicates that important components in the second and third stages of the Proton-M rocket may have been switched by workers during the construction process at the plant in Voronezh, where Proton-M and Soyuz rocket engines are built.

Workers used materials that are less heat resistant instead of those containing precious metals. Although the replacement parts would cost cheaper in the short term, cutting corners eventually proved to be disastrous for the spacecraft.

Proton-M Space Rockets Grounded For Three And A Half Months

Safety inspections of other Proton-M rockets are under way, but the Proton M, a staple of Russia's rocket fleet, will stay grounded until these are finished. Russia's space agency, however, promised to inspect all its Proton-M rockets to ensure that these are all ready for launch in three and a half months.

"Three Proton-M rockets will be dissembled and their second and third-degree engines replaced," Prime Minister Dmitry Rogozin said.

Rogozin, who visited the Voronezh plant, revealed that the workers at the there were evidently directed to switch technology and documentation. Rogozin said that those who are guilty of switching document and technology will face harsh punishment.

The head of the Voronezh factory already resigned last week, citing unsatisfactory work and product quality.

Concerns Over Rocket Quality Control

This is not the first time that concerns have been raised on Russia's rocket quality control. The Proton-M appears to be particularly prone to mishaps in recent years. Such technical issues led to crashes of unmanned rockets in 2013, 2014, and 2015.

Tampering does not only affect Russia's space program. United States is affected as well since Russia is the only country that is currently capable of launching astronauts to the ISS, which it achieves using the Soyuz rockets manufactured at the Voronezh plant.

NASA Taps Boeing And SpaceX To Ferry Astronauts Starting 2018

NASA currently has a contract with Russia's Roscosmos space agency to ferry U.S. astronauts on six Soyuz journeys this 2017 at a cost of $458 million. NASA will spend another $490 million for another six flights in 2018.

Although it is still dependent on Russia for crewed flight to the ISS, the U.S. space agency is already working with private companies SpaceX and Boeing. It has granted contracts to these companies for crewed flights to the orbiting laboratory in 2018.