The airline goes belly-up.

What happened: The airline from which you bought your ticket stops flying.

What the airline should do for you: Other airlines flying the exact route for which you hold a ticket are required by federal law to give you a standby seat for no more than an additional $50 each way.

Next time: “Protect yourself by flying only those carriers in sound financial shape,” advises consumer-travel expert Ed Perkins. (An online news search can often reveal whether a particular airline has been struggling.) And pay with a credit card: According to federal law, if you buy an airline ticket (or anything, for that matter) and don’t get what you paid for, you can contest the charge and the credit-card company must delete it from your bill. However, you must contact your card issuer in writing within 60 days of seeing the charge on your bill — so if your ticket was purchased far in advance, it may be too late to complain when the carrier goes out of business.

Your luggage is lost.

What happened: You flew to Hawaii for your honeymoon, but everything you packed for the beach went off on a vacation of its own.

What the airline should do for you: U.S. law sets the maximum lost-luggage payment at $2,800 per passenger on a depreciated basis (meaning the airline will value your items below their purchase price because they’re considered used). There’s no federally mandated compensation for luggage that is only delayed, even if the delay is significant.

Next time: Pack as lightly as possible to avoid checking bags in the first place. If that’s not possible, carry on medicines, any valuable items, and a change of clothes. If you’ve acquired a valuable or breakable souvenir that you must bring on board, ship home any less fragile items you won’t need right away, such as beach reads and guidebooks. Also, put your name, home address, and phone numbers both outside and inside your bags, along with a note indicating where you’ll be staying, advises Todd Burke, vice president of corporate communications for JetBlue, in Forest Hills, New York. And “make sure you have a list of everything you packed,” suggests Bill McGee, a travel writer with Consumer Reports WebWatch. “Or take a photo of everything laid out on the bed before leaving.” Present this documentation at the airport when you file your claim.