S42

S42 may refer to:

Aviation

• Blériot-SPAD S.42, a French biplane trainer aircraft
• Sikorsky S-42, an American flying boat
• Springer Municipal Airport, in Colfax County, New Mexico, United States

Rail and transit

• S42 (Berlin), a line of the Berlin S-Bah
• S42 (Long Island bus)
• S42 (New York City bus), serving Staten Island

Science

• S-42 (geodetic datum), used in Eastern Europe
• S42: During fumigation/spraying wear suitable respiratory equipment (appropriate wording to be specified by the manufacturer), a safety phrase
• Sulfur-42, an isotope of sulfur

Submarines

• ARA San Juan (S-42), of the Argentine Navy
• HMS Ursula (S42), of the Royal Navy
• INS Vagli (S42), of the Indian Navy
• USS S-42 (SS-153), a submarine of the United States Navy

Other uses

• IBM NetVista S42, a personal computer
• Siemens S42, a mobile phone
• Zulu language
• S42, a postcode district in Chesterfield, England