Mammoth is an automotive and aircraft company in the HD Universe.
Mammoth is obviously named after the pre-historical animal species, demonstrating the great size of their SUVs. Coincidentially, the Hummer brand, like the pre-historical animal, is now an extinct giant.
Mammoth also manufactures planes. Mammoth, like Western Company, Jobuilt and Buckingham, has a defense contract with the United States government, manufacturing the Hydra jet for the United States Armed Forces.