An electrical fault that grounded dozens of Boeing (BA) 737 Max jets last week has caused fresh concern after engineers found similar issues elsewhere in the cockpit.
Just days ago the aviation company told 16 of its operators that its most-sold model should not be flown until the “production issue” is addressed.
It said at the time that it was working alongside the Federal Aviation Administration (FAA) on the issue, which does not affect its entire fleet.
Boeing said it was not related to the flight-control system that suspended its planes previously.
However, suspected grounding problems have since been found in two other places on the flight deck, Reuters reported citing sources close to the matter.
These include the storage rack where the affected control unit is kept and the instrument panel facing the pilots.
Airlines including Southwest, American and United said they had taken more than 60 planes out of service following the notice from Boeing last week. The issue is believed to have affected about 90 planes globally.
A Boeing spokeswoman said at the time that it was unclear how long it would take to solve the problem.
The global fleet of in-service 737 Max is currently a total of 176 aircraft, according to Cirium fleets data. Those jets are operated by 22 airlines, most based in North and South America, but with some based in Europe, Cirium shows.
The new issues are not related to the design problems that contributed to a 20-month worldwide suspension following two fatal crashes in Indonesia and Ethiopia that killed 346 people.
Lion Air flight JT610 crashed off Indonesia in October 2018. Five months later, Ethiopian Airlines flight ET302 crashed minutes after take-off from Addis Ababa.
Investigators believe the accidents were triggered by the failure of a single sensor, specifically the MCAS software, as well as the regulatory oversight failures of the FAA, and the lack of training provided to pilots.
Boeing is expected to draw up bulletins advising airlines how to fix the problems with the latest grounding, or the electrical paths designed to maintain safety in the event of a surge of voltage, Reuters said.
The bulletins must first be approved by US regulators.
It comes as Boeing’s total aircraft orders fell by around 800 jets in the last 12 months as the coronavirus pandemic wreaked havoc on the industry.
According to the World Travel and Tourism Council (WTTC), income across the travel sector fell by almost $4.5tn (£3.2tn) last year, putting more than 62 million people out of work.
It is pressing for international travel to resume in June to stem further job losses.
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