6th of May, 1980, 5:32pm if i remember correctly.
The SAS made a raid on the Iranian Embassy in Princess Gate, London.
The US had nothing to do with it, you might be thinking of Operation: Eagle Claw in Iran, where 1SFOD-Delta attempted their first real rescue, a Sea Stallion flew into a grounded C-130 spilling fuel into the props, sending it everywhere, everything caught fire, and a bunch of blokes kicked the bucket to put it bluntly.
Do your research mate