| Convoy ON 166 | |||||||
|---|---|---|---|---|---|---|---|
| Part of Battle of the Atlantic | |||||||
 A depth charge being loaded onto a depth-charge thrower aboard the corvette HMS Dianthus | |||||||
| |||||||
| Belligerents | |||||||
 United Kingdom United States Canada Poland |
 Germany | ||||||
| Commanders and leaders | |||||||
|
CAPT W E B Magee RN CAPT P.R. Heineman USN | Admiral Karl Dönitz | ||||||
| Strength | |||||||
|
63 freighters 1 destroyer 2 cutters 5 corvettes | 18 submarines | ||||||
| Casualties and losses | |||||||
|
14 freighters sunk (87,994 GRT) 262 killed/drowned |
3 submarines sunk 128 killed/drowned 11 captured | ||||||
Convoy ON 166 was the 166th of the numbered ON series of merchant ship convoys Outbound from the British Isles to North America. Sixty-three ships departed Liverpool 11 February 1943 and were met the following day by Mid-Ocean Escort Force Group A-3 consisting of the Treasury-class cutters Campbell and Spencer and the Flower-class corvettes Dianthus, Chilliwack, Rosthern, Trillium and Dauphin.