He served as mate aboard HMS Erebus during the 1845 Franklin Expedition which sought to chart the Canadian Arctic, including the Northwest Passage, and make scientific observations.

[1] His great-grandfather Anthony Vinchon de Bacquencourt moved from France to Ireland after renouncing his Catholic faith in favour of Reformed Christianity, and changed the family name to Des Voeux.

[9] During the preparations for the expedition, James Fitzjames selected Des Voeux as mate due their time together on HMS Cornwallis during the First Opium War.

On 24 May 1847, Des Voeux, Graham Gore, and six seamen set out to travel along the west coast of the island in order to ascertain and chart the geographical positions of all the land forms they came across.

In April 1848, Fitzjames and Francis Crozier added an addendum to the record explaining they had deserted the ships and were heading south to Back River on the Canadian mainland.

[3] David C. Woodman has argued there is evidence that the main group knew of a shortcut across what is now called Graham Gore Peninsula, which separates Erebus Bay from Terror Bay and saved time from travelling along the coast, but that the 1847 Gore and Des Voeux sledge party did not, suggesting that a skeleton found there could belong to Des Voeux.

[15] Inuit from Repulse Bay found various Franklin Expedition artefacts at a camp near the mouth of Back River where many Europeans had starved to death.