Boeing error uncovered

BOEING knew about problems with its 737 Max jetliners a year before they were involved in two fatal crashes, it has emerged.

Staff discovered an alert system was not activated on some of the single-aisle aircraft in 2017 but decided not to take immediate action, the firm admitted.

Known as the angle-ofattack disagree alert, the software is meant to show if a plane’s sensors are contradicting each other and alert pilots so they can take action. But Boeing said an error meant it only worked if airlines bought it as an optional extra.

All 737 Max planes have been grounded since March after 157 people died when an Ethiopian Airlines plane crashed, five months after 189 died in a Lion Air plane crash.