Flying elk meat back is nearly as much an adventure as the hunt itself, particularly if you are by yourself.
Delta charges checked bags (50lbs) of $30 for first bag, $40, $150 and $200 for each after that...I check 150 lbs of meat...I then have put about 35 lbs of frozen meat in a dry bag in back pack as carry-on and another 15 lbs in a smaller drybag I carry onto the plane. I also check in my rifle.
I have simply put wrapped, frozen meat in 40 liter dry bags from Walmart...They are the perfect size for 50 lbs...No issues and no leaking...Meat has stayed frozen from both Missoula and Denver to NY. Have been lucky enough to do this 5x.
It is a pain and even moreso if you are by yourself.
Last fall, my return trip was first class...comes out only slightly more expensive but allows first two checked bags at 70 lbs "free"...plus, you don't have to be one of those guys walking to the back of the plane with 70 lbs in your "carry on."
Check your baggage limits. My flights only allow up to 4 checked bags.
I measure tips of antlers before splitting them and sending them back with my clothes via UPS.
If you tag out late in your hunt, there is the challenge of getting it to the butcher in time to have it cut, wrapped and frozen for your return flight.
Lastly, I suggest you have a minimum of an hour layover for any connecting flight.
Take care. Mike