Time travel brings us this week’s Marketplace Money buzzword: Block time.

Block time is the time airlines say it’ll take to get from one place to another. Summer travelers might be a wee bit surprised to learn the Earth is growing. Or at least, that’s what carriers must want you to think, because some routes are taking longer – sometimes 30 minutes longer than 10 years ago.

What’s the real deal? Many airlines are accounting for expected flight delays by changing their block times. Then they can tell regulators a flight that’s 20 minutse late was actually on time. Hey, but at least their food is awesome.