Spirit is on the brink of collapse. If it disappears, airfares will almost certainly rise.Scott Olson/Getty ImagesSpirit Airlines is on the brink of collapse and is warning of possible liquidation.If Spirit disappears, travelers are likely to feel the impact quickly.A Business Insider analysis of airline fare data shows a Spirit fold would hike prices roughly 14%.Your cheap fare to Florida could soon be a lot more expensive.After a failed merger…