A United Airlines-led roundtrip fare hike of $4 to $50 has survived

, marking the fourth broad domestic price increase in as many weeks, according to FareCompare's Rick Seaney. "It's all about the high cost of jet fuel," according to Seaney's Web site. "Travelers better prepare themselves for more inconvenience and packed planes (if that's even possible) along with higher prices for the foreseeable future."