Reports that a Boeing 737 MAX 8 flown by two Southwest pilots had to make an emergency landing yesterday due to an unspecified "engine issue" - a malfunction that, the airline insisted and the media uncritically accepted, had nothing to do with the software issues identified in two recent deadly crashes - hardly inspired confidence in aerospace company. But that didn't dissuade a bevy of bullish Wall Street analysts, who reinstated their 'buy' rating on Boeing's shares on Wednesday.

After reinstating coverage of Boeing, Citigroup analyst Jonathan Raviv sketched out "a path to $500" - which would erase Boeing's entire 12% post-ET302 drop, plus another 5%. The bank's 'base case' involves a multi-month grounding before the MCAS software fix is approved, allowing the 737s to return to the sky.

But if these upgrades seem premature, it's probably because they are: Just look at the balance of this week, which is peppered with event risk.

On Wednesday, FAA officials will appear before the Senate's Subcommittee on Aviation and Space - likely the first of many expected hearings - to explain how they approved the plane and its MCAS anti-stall software without detecting the glitch that forced the noses of two planes lower, forcing them into a deadly tailspin. Then there's the federal investigation into exactly what led to the accidents. Meanwhile, Boeing has been working furiously to revamp MCAS and make sure the proper training materials are available to all pilots, and the final software update is expected before the end of the week, assuming the FAA approves.

Courtesy of Bloomberg

Aviation consultant Robert Mann told Bloomberg that, if all goes well, the update could get the 737 MAX, Boeing's fourth generation installment in its 737 line, back in the sky within a few weeks (presently, the planes can't be flown with passengers aboard, though airlines can still fly them with only pilots. Southwest has been moving its fleet to a storage area in Victorville, Calif.)

But what isn't clear is whether global regulators, who once followed the FAA's lead, will uncritically accept the regulator's assessment this time. Officials in China, Canada and the EU, who grounded the plane before the FAA, have said they would independently verify the plane's safety before giving it the all-clear. That's a break from historical precedent.

Peter Goelz, a former managing director of the NTSB, said this skepticism likely means the reintroduction of the 737 MAX will be staggered.

"It may mean that there's a staggered reintroduction of the aircraft into service," Goelz said. "The FAA is going to have to embark on a mission to restore its credibility" with international regulators who have grounded the plan.

But whether Boeing can convince the public that the planes are safe is another matter entirely. Whatever the aerospace company does, it needs to be "pretty definitive", said Mark Gerchick, a Washington lawyer who previously served as FAA's general counsel.

"People have to say, 'Ah, I get it.' It's a question of public confidence."