A suitcase measuring 22 inches high by 14 inches wide by 9 inches deep -- or smaller -- meets several domestic carriers' carry-on allowances, including American, Delta, United, and JetBlue. Some are more liberal. Virgin America says 24 inches by 16 inches by 10 inches is OK. Some airlines measure bag size in linear inches, and 45 linear inches (22 + 14 + 9 = 45) is a frequent acceptable allowance.
International carry-on restrictions are often tighter. For example, Air France's allowance is 21 inches by 13 inches by 9 inches. Regional jets are even stricter, and some have been known to disallow all wheeled bags, regardless of size. However, though you may have to check a bag on a regional flight, it's usually free, and the bag is typically waiting for you when you deplane.
Scott Applebee, vice president of marketing for luggage maker Travelpro, offered these tips for people researching a new bag purchase:
1. Many bag dimensions apply to only the main compartment. To estimate a bag's complete measurements, it's a good idea to add about an inch in height for two-wheelers and 2 to 3 inches for four-wheel "spinners." The wheels on two-wheel bags are often more recessed than those on four-wheel spinners. As a result, some spinners offer less packing space than comparable two-wheelers.
2. Look for rollaboards with flexible top carry handles that can be flattened down, and keep in mind that firm, arched handles add height.
3. You might want to err on the safe side and only consider rollaboards advertised as 19 inches or 20 inches tall. You'll get less packing capacity, but they're more likely to fit on board planes.
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