The U2 Live at Red Rocks show on kcuvradio.com right now just had an interview with one of the producers for the video Under a Blood Red Sky. He stated that the helicopter pilot was unable to take off from Denver due to the horrible weather. After he said how badly he needed the shot for the introduction to the video, the pilot suggested putting the helicopter on a truck and driving it to another location. This was accomplished, the helicopter got airborne and the shot was in the can as they say. See the image below. I’m a pilot and I wouldn’t have flown in that weather.
In case anyone is wondering, the music from the intro is “Theme From Harry’s Game” by Clannad.