Aggressive,
strategically mis-placed, expansion. Other airlines, e.g. Spirit, are expanding profitably on their ultra low-cost carrier (ULCC) model.
The airline industry is being commoditised - Virgin America is trying to move against that trend [1]. What is happening is more fundamental than ill-timed expansion; it's a rejection of Virgin America's core hypothesis (U.S. air travellers will trade low prices and a bit of convenience for a delightful experience). An analogy could be Verizon trying to swim against the global trend towards carriers becoming dumb pipes.
The new routes Virgin America is opening are losing money; Virgin America is presently rolling back select routes [2]. This lends is more consistent with a bad strategy versus 'unlucky exposure to unforseeable systemic factors' hypothesis.
Further evaluating the specific factors to Virgin America versus expansion-related woes hypothesis, one notes that Spirit Airlines (NASDAQ:SAVE) spent 3.6% (44.2%) of revenues (operating cash flow) on capital expenditures in 2011. Delta spent 0.1% (8.2%). Average CAPEX/Revenues spread between Spirit and Delta from 2008 to 2011 was 3.5% (Delta has been out-spending Spirit in 2012). Spirit is generally profitable.
Virgin is betting on a strong consumer or business travel spending recovery in the U.S. If that happens , temporarily depressing costs will work out fine if it can stay solvent long enough to be proven right. If the recent shifts are structural changes, however, they're out of luck.
[1] http://www.economist.com/blogs/gulliver/2012/10/virgin-ameri...
[2] http://www.businessweek.com/news/2012-10-17/virgin-america-t...
[3] http://www.sec.gov/Archives/edgar/data/1498710/0001498710120... Spirit Airlines Q3 10-Q Filing