The U.S. Army is having an interesting competition with the U.S. Navy over which is the best way to teach troops to parachute out of an aircraft. For over half a century, the army has run its "jump school" as a 21 day course. The navy set up its own school recently, and does it in five days. Why the big difference? The army treated Jump School as a physical conditioning course, as well as parachute training. The navy just teaches the parachute stuff. Another difference is that most of the soldiers going to jump school had been in the army for less than a year, and were still getting in shape. The navy was sending SEALs, marines and other experienced operators to their "Parachute and Free-Fall School." The army is not amused, but the navy approach appears to work.