N460UH, operated by Orbic Air, is ex US Army 83-23841 and has been prepared by Pickering Aviation to be certified in the FAA "Restricted" category. As such, it can only be used for limited aerial work of public interest, like e.g. fighting forest fires. Helitak's Fire Tank FT4500 system - seen here mounted under the airframe - can take on 1100 US-Gallons of water in less than a minute, expanding under the belly. After the drop, it automatically retracts to its empty profile of just 12 inches.