Antonov An 990 !link! Page
6,000 tonnes (13.2 million lbs), which is roughly 120 times heavier than a classic Boeing 737-100.
: An Ultra-Heavy Air Tanker / Water Bomber . The aircraft is theoretically designed to suppress megafires across California, Canada, and Australia by dumping millions of liters of fire retardant in a single pass. Digital Flight Performance and Challenges antonov an 990