In World War II, Operation Quicksilver (Allies, 1944) was a sub-plan of Operation Fortitude, the 1944 deception plan. Quicksilver created a fictional "First United States Army Group" commanded by General Patton that supposedly would invade France at the Pas-de-Calais. American troops used false signals and decoy installations and phony equipment to deceive German observation aircraft and radio intercept operators. See Operation Bodyguard.
Operation Quicksilver (United States, 1978 - 1979) was a nuclear test series of eighteen blasts conducted at the Nevada Test Site in 1978 and 1979. This preceded Tinderbox, and followed Crescent. The individual tests were:
| Name | Date | Size |
|---|---|---|
| Emmenthal | 2 November 1978 | <20 kilotons |
| Quargel | 18 November | 20-150 kilotons |
| (Unknown) | 1 December | (Unknown) |
| Farm | 16 December | 20-150 kilotons |
| Baccarat | 24 January 1979 | <20 kilotons |
| Quinella | 8 February | 20-150 kilotons |
| Kloster | 15 February | 20-150 kilotons |
| Memory | 14 March | <20 kilotons |
| (Unknown) | 11 May | (Unknown) |
| Pepato | 11 June | 20-150 kilotons |
| Chess | 20 June | <20 kilotons |
| Fajy | 28 June | 20-150 kilotons |
| Burzet | 3 August | 20-150 kilotons |
| Offshore | 8 August | 20-150 kilotons |
| Nessel | 29 August | 20-150 kilotons |
| Hearts | 6 September | 20-150 kilotons |
| Pera | 8 September | <20 kilotons |
| Sheepshead | 26 September | 20-150 kilotons |
3. Operation Quicksilver (United States, 1990s) was a plan to reduce the size of the United States Army in the early 1990s as a result of the end of the Cold War. A number of incentives such as early retirement were used to reduce the number of soldiers on active duty by a third.