An earlier version of MCAS has additional safeguards, WSJ reports

New York City, U.S. - The Wall Street Journal reports that Boeing disregarded some safeguards for the 737 MAXs, which were already used for MCAS system on a military air-to-air refueling aircraft.

According to the WSJ, the Maneuvering Characteristics Augmentation System (MCAS) designed for a tanker aircraft relies on inputs from multiple sensors and limits the system's ability to change the aircraft's Angle of Attack (AOA) in order to prevent the pilots to lose control, if the system acts erroneously.

But the 737 MAX version of the MCAS relied on input from just one of two sensors to intervene and change the AOA (Angle of Attack) of the aircraft. In addition, the system does not allow pilots to regain control even if it acts erroneously.

Also read: How the Boeing MCAS System Really Works

Boeing has been working on an updated version of the MCAS to return the grounded aircraft into the service. The fixes on the system are expected to be more like the one used on the Boeing's tanker aircraft, Wall Street Journal reports.

Boeing 737 MAX MCAS system was found to be the cause of two fatal crashes in Indonesia and Ethiopia, which killed 346 people.

The 737 MAX series jets have been grounded after the second crash in Ethiopia on March 10.