Tanker work over California
The 747 Supertanker is one of several aerial firefighting air tankers derived from various Boeing 747 models. The aircraft are rated to carry up to 19,600 US gallons (74,000 L) of fire retardant or water. They are the largest aerial firefighting aircraft in the world.
Initially developed by Evergreen International Aviation, the first Supertanker was based on a 747-200 (N470EV, tanker/tail number 947), and never entered service. The second Supertanker (N479EV, tanker/tail number 979) was based on a 747-100 originally manufactured by Boeing in 1971 for Delta Air Lines.
It entered service for the first time in 2009, fighting a fire in Cuenca, Spain, and made its first American operation on August 31, 2009 at the Oak Glen Fire in California. It is no longer in service.
The third 747 Supertanker was developed by Global Supertanker Services which acquired most of Evergreen’s assets. The Global Supertanker (N744ST, tanker/tail number 944) is a Boeing 747-400 dubbed the Spirit of John Muir. It was certified for firefighting flights by the Federal Aviation Administration in September 2016 and fought fires in Chile and Israel before being contracted by U.S. officials to fight California wildfires in 2017. It also took part in firefighting in Bolivia in August 2019.