On the back of yesterday's minor gains, stocks opened lower this morning, with the S&P 500 (SNPINDEX:^GSPC) and the narrower, price-weighted Dow Jones Industrial Average (DJINDICES:^DJI) down 0.2% and 0.21%, respectively, as of 10:05 a.m. EDT.

Things are looking up for Boeing
The good news keeps on coming for investors in Dow component Boeing (NYSE:BA). Yesterday, I highlighted a report according to which the company has snagged a massive order for 200 aircraft worth $18 billion from budget airline Ryanair. Right after that, the Federal Aviation Administration approved Boeing's measures to address the overheating problem of the 787 Dreamliner's lithium-ion batteries, which caused the federal regulator to ground the aircraft following a series of incidents in January.

The approval means that test flights can begin, with Boeing targeting a resumption of commercial flights within three to four weeks -- which is consistent with reports that surfaced last month regarding the company's expectations.

If this schedule holds up, I'll end up with egg on my face. In February, I wrote: "An early April reinstatement date looks optimistic. ... Boeing was repeatedly over-optimistic when it came to the delivery date of the 787; investors can expect further delays in the planes' (and the shares') current flight schedule."

Nevertheless, something still doesn't sit right with me. If you look at Boeing's proposed "fix," it consists of:

  • Improving insulation between battery cells in order to prevent a short-circuit in one cell from igniting the entire unit.

  • Putting the battery in a fire-resistant box.

  • Allowing smoke from any overheating to vent outside the aircraft.

Where is the fix? These measures address the effects of the problem, not its cause. Indeed, the latter is, at this stage, impossible to resolve. On Monday, The Wall Street Journal reported that the National Transportation Safety Board has so far been unable to determine the root cause of the lithium-ion battery fire on a parked 787 at Boston's Logan Airport. According to an NTSB report released last week, the battery in that incident was glowing with heat that had melted many of its most resistant components. In that context, I'm not sure that yesterday's FAA decision is consistent with Transportation Secretary Ray LaHood's January pledge that "those planes aren't going to fly until we are 1,000% sure that they are safe to fly."

Fool contributor Alex Dumortier, CFA has no position in any stocks mentioned; you can follow him on LinkedIn. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.