Sulfate-reducing microorganisms are responsible for the sulfurous odors of salt marshes and mud flats. Much of the hydrogen sulfide will react with metal ions in the water to produce metal sulfides. These metal sulfides, such as ferrous sulfide (FeS), are insoluble and often black or brown, leading to the dark color of sludge.
The largest aircraft used for a scheduled domestic service in the USA that is a DOMESTIC route only, is the Boeing 777, though the most common is a Boeing 757 and 767. Some airlines use larger aircraft on domestic legs on an international flight throughout the USA, which do include the 747, however some airlines don't have a license to carry domestic passengers on those routes.
The Antonov An-225 Mriya is a cargo aircraft that was designed by the Soviet Unionâs Antonov Design Bureau in the 1980s. It is powered by six turbofan engines and is the longest and heaviest airplane ever built, with a maximum takeoff weight of 640 tonnes. It also has the largest wingspan of any aircraft in operational service. Only one An-225 was ever built and the behemoth transporter is still in service today.