Try this for an exercise.
This time last week, we were working a fire SE of Mathoura.
35°51'8.33"S
144°56'50.83"E
For those who don't know the area, it's floodplain occupied by the world's largest forest of River Redgum. It's also got a lot of reed or cane-grass beds that the locals estimate have fine-fuel loads of up to 100t/ha. We were running three ATs off the Deniliquin strip, on about 25-minutes turnaround.
Would anyone care to whistle up an online map and nominate a spot that'd be suitable for scooping?
Double-Wasp makes a very valid point in saying that we need to distinguish between the use of short term retardants (Water and foam, effectiveness limited to 20 minutes on a 40c day) and long-term retardants such as Phoscheck. Short-term retardants are of very limited use if we don't have people on the ground.