So, being generous, a S-92 with aux tank fitted has 5100 (main fuel) plus 1400 (aux fuel) giving 6500 lbs. Take off 30 mins on scene and 30 mins reserve (don't know what min landing fuel is) and assuming 1300 lbs /hour fuel burn leaves you 5200 lbs useable.
At 1300 lbs/hour that gives 4 hours flying at 137 kts (again being generous) equals 548 nm or 274 nm Radius of action).
Not actually such a capability improvement when all is said and done despite all the trumpeting.
If there is an option of a second 210 gallon aux tank that will add another hour of flying at 137 kts which takes the RoA up to 342 nm yet the Sikorsky/MCA blurb, that 212 mans link takes you to, show RoA's in excess of 370 nm. More fudge factors cherry picking the best possible (rather than realistic everyday) performance figures from the RFM?