BK117B2 Performance Cat A VTOL (as the pad would be),
All figures are for the WA Police BK with EMS fit so might vary slightly:
Basic Weight 2050kg, with kit (Pilot, Doc, medic + patient) = 2510kg
Max Weight 2900kg corrected for DA (Doesn't include medical equipment but does include stretcher)
Elev zero ft
ISA = Max 2830kg, = 320kg fuel
ISA+10, 2760kg, Fuel 250kg
ISA+20, (a stretch for wellington me thinks), 2700kg, 190kg fuel
so it is doable for arrival off a job.
