The Underwater Archaeology Search for Franklin's Lost Vessels: HMS Erebus and HMS Terror National Historic Site

The Vessels

HMS Erebus (Hecla Class)

Constructed: Pembroke Dockyards, Wales, as a bomb vessel
First Launched: 7 June 1826
Dimensions: 105 feet (32 m) long; 28.5 feet (8.7 m) wide; 13.8 feet (4.2m) draught
Displacement: 372 long tons
Original Armaments: 2 mortars; 10 cannons
Original Propulsion: Three-masted sailing ship

Notable Actions: Participated in James Clark Ross' Antarctic Expedition 1839-1843

HMS Terror (Vesuvius Class)

Constructed: Davy Shipyard, Topsham, England, as a bomb vessel
First Launched: 29 June 1813
Dimensions: 102 feet (31 m) long; 27 feet (8.2 m) wide; 22.5 feet (6.86 m) draught
Displacement: 325 long tons
Original Armaments: 2 mortars; 10 cannons
Original Propulsion: Three-masted sailing ship

Notable Actions: Served in the War of 1812 as a bomb vessel; participated in Sir George Back's Arctic Expedition 1836-1837; participated in James Clark Ross' Antarctic Expedition 1839-1843


Both HMS Erebus and HMS Terror were built as Royal Navy bomb vessels and carried mortars mounted on a rotating platform at the ship's centreline, near the bow. The high angle of these mortars allowed them to fire explosive shells over long distances. Bomb vessels were designed for bombarding fixed positions on land, such as artillery formations, harbour installations and forts.

In order to support the strong recoil from the mortars, the rotating platform had to be supported by a strong internal wooden framework. Many bomb vessels were converted for peacetime exploration in the Arctic and Antarctic because this robust construction provided them with a greater chance of withstanding the constant menace of pack ice and icebergs.

The Royal Navy had used both ships for many years before they were assigned to Franklin and Crozier. HMS Terror, as the older vessel, saw action during the War of 1812. Notably, it was one of the ships involved in the bombardment of Fort McHenry, one of the war's last battles. The bombardment provided the inspiration for Francis Scott Key to write the American national anthem 'Star Spangled Banner.' After being retrofitted for polar exploration, HMS Erebus went to the Arctic with Sir George Back [National Historic Person] in 1836-37 and both ships participated in James Clark Ross' Antarctic Expedition 1839-1843.