What happened

Shares of American Airlines Group (NASDAQ:AAL) leapt as much as 5% higher in Tuesday trading, before settling down to book a 4.8% gain by market close.

So what

American Airlines reported its April and year-to-date traffic results earlier today. Total revenue passenger miles (RPMs) hit a record 18.6 billion in April, up 3.1% versus April 2016. Although the airline increased capacity (total seats flying) by 0.8% year over year, it increased the pace at which it put passengers in those seats even faster. The airline's passenger load factor -- the percentage of seats flying that were occupied by paying passengers -- increased to 82.2%, up 180 basis points over last April.

This marked a bit of a turnaround from results earlier this year. To date, 2017 RPMs have been down 0.3% year over year, while capacity has been down 0.6%, and the load factor is up only 0.2%.

American Airlines plane in flight

American Airlines stock just took off. Image source: American Airlines.

Now what

In other words, while some investors might be concerned to see American Airlines adding capacity (given that more capacity increases the chance that some will go unutilized, hurting profits), so far things seem to be working out well. American is putting more planes into service and it's still filling those planes more efficiently.

This quarter, American Airlines says it could conceivably grow revenues as much as 3.5% to 5.5%, and expects to earn operating profit margins of between 12% and 14% on those revenues. This good news has the potential to inspire a rash of analyst upgrades before earnings come out.

Little wonder investors are positioning themselves to benefit if and when those upgrades materialize.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.