What happened?
Bolstered by a growing fleet of planes, upstart airline Virgin America (VA) has reported several big improvements in its core metrics. The company recently released its February operating figures, which reveal that it flew around 546,000 passengers during the month -- 20% higher than the February 2015 tally.

Image source: Virgin America. 

Other measurements saw roughly the same growth in percentage terms, with available seat miles and revenue passenger miles (the number of passengers times distance traveled) also increasing, to just over 1 billion and 804 million, respectively.

However, passenger load (i.e., the collective occupancy of its planes) was essentially flat on a year-over-year basis, dropping roughly 30 basis points to 78.9%.

Does it matter?
A 20% rise in those base passenger figures is an encouraging bump for any airline, and investors should find it heartening. As of the end of last year, Virgin America's fleet had 60 aircraft, up from 53 at the end of 2014 -- a 13% improvement, so it's no surprise that capacity rose like it did. To some degree, then, the reported growth was expected, and it shouldn't add too much lift to the stock price.

Regardless, it'll enhance sentiment for Virgin America. The company's done a good job carving out a niche in its business, offering a relatively more pleasant and roomier flying experience than its rivals while staying competitive on price, and opening attractive new routes. It could probably do better filling its planes -- United Airlines' domestic load factor was 81.5% for February, while Delta's clocked in at 80.9% for the month. -- but with fuel as cheap as it is these days, load factor isn't such a critical factor. Times are good for the industry, and Virgin America is gliding along.