Boeing Co. is targeting late June for a recertification flight on the grounded 737 Max and is notifying airlines of a key fix to the jetliner’s wiring in signs that the troubled jetliner is nearing a return to service.

A draft of revised pilot training for the plane, which has been parked around the world since March 2019 as a result of two fatal crashes that killed 346 people, is also being shared with airlines, said two people familiar with the planning who asked not to be named discussing sensitive matters.

Boeing pared a decline on the news, falling 5.3 per cent to US$205.20 at 12:11 p.m. in New York after dropping as much as 8.9 per cent amid a broader market slump. The company’s shares were down 37 per cent this year through Tuesday, while the S&P 500 slipped 1.1 per cent.

The moves were strong indications that after more than a year of the company’s best-selling jet being grounded and controversy surrounding its two fatal crashes, it is nearing the final stages necessary for a resumption of service.

The date for a flight by Federal Aviation Administration pilots to certify that the plane meets safety regulations hasn’t been finalized and one person cautioned that the company still has items to complete before it can occur.

Boeing’s goal has been to return the 737 Max, a critical source of revenue, to commercial service in the third quarter. The Chicago-based company restarted manufacturing the single-aisle jet late last month, ending a five-month halt to work in its 737 factory in the Seattle suburb of Renton, Washington.

The company is revising a software system implicated in the two crashes that repeatedly drove down the noses of the jets due to a malfunction. Reviews of the plane’s safety following its March 13, 2019, grounding also discovered additional flaws that needed upgrading, including its flight-control computer, how electrical wires were bundled and software issues.

The FAA is also broadly reviewing how it assesses pilot performance during malfunctions as a result of the crashes.

If all goes as planned, the jet will return to a market far different from that of March 2019, when regulators halted Max flying. A global pandemic has plunged the travel industry into its sharpest downturn on record, and many customers who were clamoring for Max just months ago are now fighting for survival.