The LORAN-C transmitter Jan Mayen was a LORAN-C transmission facility on the island of Jan Mayen at 70°54′51″N 8°43′57″W / 70.91417°N 8.73250°W. The LORAN-C transmitter Jan Mayen used as an antenna had a 190-metre tall (625 ft) guyed mast. This mast was built as a replacement of a 190.5 metre tall mast, which collapsed in a storm on 8 October, 1980 as the result of low tension on the guy-wires. The guy-wires were adjusted by personnel from the USCG who mixed up pounds and kilograms. The transmitter was demolished in 2017.