The real number is somewhere between 2600-2700 ord damage needed to remove a hangar, at least from my testing.
The real number for (almost) any object in any arena can simply be found by looking at the arena settings:
Options->Arena Setup->Objects->Object Settings. The number given is how many 1000lb bombs are necessary to destroy the object. So a VH has the value 2.7815 which translates into 2,781.5 lbs. That means it would take
3 x 1000lbs bombs (damage rating 1000 each) or
5 x 500lbs bombs (à DR 562 each) or
18 x 100lbs bombs (à DR 156 each)