Agree, it's up to the airline. eBags has a chart showing the different "rules" by airline, seems the most common measurement is total linear dimension not to exceed 45 inches, but as mentioned print out policy as its a crap shoot if gate agent knows or not. Based on your dimensions above, you might be in trouble, but I've seen some 9ft 2 piece tubes allowed so give it a shot. Also, take a fabric measuring tape with you to "prove" you are in policy, sometime you can win that argument. Another thing to check is that SeatGuru will have the specific dimensions for the overhead configuration of your flight, 737 should have big enough compartments but check to be sure. Also eastcoast is right, never have issue when sitting in front of the bus, even had them put tubes in closet for me, sometimes is worth the upgrade. I feel your angst, going to WV next week for week of smallmouth fishing, been agonizing over my carry on for days. Good luck