Airtankers performance is actually determined using the Cup & Grid method.
The Cup&Grid method consists in collecting on cups distributed on a flat field the quantity of product released by an Airtanker. This method is fastidious, expensive and long to implement. 

Nasca Software developed by Pr. Dominique Legendre ( is able to provide in few seconds the main characteristic of the drop pattern of any air tanker system from heli-bucket to hi-pressurized systems.
Nasca has been validated on the data base provided by the USDA Forest Service in California and the CEREN in France. Nasca can be used for the design of new systems (as the KIOS for the Kepplair-Evolution A330) as well as the optimization of existing systems.