After what has seemed like an eternity, Boeing (NYSE: BA) confirmed in yesterday's first-quarter results what analysts have been anxiously waiting to hear for years: The company will begin delivering 787s in the third quarter.

It's no secret that Boeing has put a substantial amount of capital into developing the 787, and it remains the biggest drag on the company's profit potential. Despite this drag, the company reported earnings results which easily surpassed Wall Street estimates. Boeing reported a $0.78 quarterly profit, handily beating the $0.70 consensus, but it fell short on revenue, reporting $14.91 billion versus the $15.27 billion consensus.

Learning to fly
Overall, the results were mixed. On the upside the company's backlog rose yet again, and its effective tax rate dropped significantly. Probably the most surprising (and encouraging) aspect of the company's report was the strength in its defense, space and security segment. Specifically, the company's military segment turned a 5% increase in revenue into a 37% jump in earnings.

Learning to fall
On the flip side, Boeing reported an increased pension charge and delivered four fewer commercial airplanes than it did in the year-ago quarter. These lower deliveries led to a 5% drop in revenue and a 25% drop in operational earnings from the commercial airplanes segment. More concerning might be the 100-basis-point fall in operating margin, as research and development costs continue to rise, but results (i.e. the 787) continue to be put off for future quarters. Full-year guidance also came in within the current guidance range of $3.80 to $4.00, but fell short of the $4.08 consensus.

Spreading its wings
By the end of the third quarter, we should have our first genuine look at Boeing's true profit potential. Currently trading at a three-year high, the company has some high expectations already baked into its valuation. I'm not quite sure that Wall Street could deal with another potential setback in the 787, and I highly doubt shareholders would be so kind.

The company also needs to keep a close eye on its expenses, which have crept up moderately compared to this time last year. Effective tax rates and pension charges will change quarter to quarter, but the company can do a better job of regulating research and development expenses and make an attempt to deliver more planes on time.

Rivals Northrop Grumman (NYSE: NOC) and General Dynamics (NYSE: GD) both beat earnings expectations as well, but concerns remain about whether the government will reduce defense spending. It's important for Boeing to produce solid results in the second half of this year from its commercial airline segment, just in case competition in defense spending heightens.

I'd call this report cautiously optimistic. But it appears Boeing will once again need a push in the right direction before it begins to fly on its own.

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Fool contributor Sean Williams has no material interest in any companies mentioned in this article. He would like to remind you not to forget about our friends in Japan who could still use a helping hand. You can follow him on CAPS under the screen name TMFUltraLong. The Fool owns shares of Northrop Grumman and General Dynamics. 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 that never gets motion sickness.