Excellent Endurance

What's the minimal distance an aircraft needs to gain the Excellent Endurance special ability? Here's the range (in miles) of some:

G3M "Nell"                            2, 700  
G4M "Betty"                          1, 772 
Ki-21 "Sally"                         1, 700
B-17 "Flying Fortess"             2, 000
B-29 "Super Fortress"            3, 250

Also, what would be the maximum distance, 3, 200? Pretty sure the B-29 could travel the farthest.