The U.S. Department of Transportation keeps tabs on the numbers of lost, damaged, delayed or pilfered baggage, and the statistics can be sobering. In the first nine months of 2012, Delta reported 155,859 mishandled bags (for 73,852,423 passengers) -- and it did better than United, Southwest, American and U.S. Airways.

No one likes it when bags go missing, not even your airline since it may need to pay for lost goods and lose any fees a flier paid to check the bag in the first place.

But mistakes happen. According to the DOT, if your bags aren't on the conveyor belt when you arrive, you should wipe away your tears and get tough: "File a report with the airline before you leave the airport. Insist they fill out a form and give you a copy, even if they say the bag will be on the next flight. Get the name of the person who filled out the form and a phone number for follow-up. Confirm that the airline will deliver the bag to you without charge when it's found."

But there are things you can do to diminish the possibility that your bag will be lost or tampered with. Arrive at the airport on time so the airline can process your bag and get it to the airplane before takeoff. Put your contact info and itinerary in an outer pocket of the bag. Use a TSA-approved lock.

Delta customers have another trick at their disposal. The Fly Delta app, which allows people to download boarding passes, also lets you track your luggage. Just click on the "track my bags" link and input the number from your baggage receipt (iPhone users can scan the receipt) to learn your bag's location and at which carousel it will arrive. The app is free.

Send your questions or tips to travel editor Kerri Westenberg at travel@startribune.com, and follow her on twitter @kerriwestenberg.