The larger airlines seem to agree on how to accommodate musical instruments. Most allow you to walk aboard with a smaller case at no extra charge.
But it’s always best to be armed with the knowledge of your airline’s policies and here they are!
Carry-On Dimensions: 10 x 16 x 24 inches
Personal Item Dimensions: 8.5 x 13.5 x 18.5 inches
If your musical instrument (including case or covering) exceeds carry-on restrictions, it CAN be carried onboard.
The instrument must fit in an overhead bin or under a seat onboard the aircraft.
Space in overheard compartments is NOT guaranteed. Seats may be bought for larger instruments that do not fit in the overhead compartment at a price “no greater than the Child’s Fare.”
Southwest assumes no liability for any damage sustained to the item during transport.
American Airlines will only be liable for damages to musical instruments if your instrument is in a hard-sided case and the outside of the case is visibly damaged.