Any moons ago when I was a Tech Rep on the Atlas ICBM I had the misfortune of standing beneath two 1000-Pound thrust solid rockets. They were running a test of the flight control RADAR and were painting the launch complex. Although the squibs in the rockets were properly grounded the RFI energy level was sufficient to fire the squibs. It was like a shotgun going off next to my ears.
In a similar case in Vietnam a large cargo aircraft had landed and had not shut down its’ RADAR. The beam painted a Cobra that was going out on a mission. The RFI fired the squibs on the FF rockets and fired the ammunition for the gun. The ammunition was fired electrically and it all went off at the same time. The missiles fired and went down to the end of the airfield and exploded and the helicopter was totally destroyed by the exploding ammunition.
The wires leading to the squibs on the hoist should be a twisted pair and properly shielded to minimize transformer coupling from the electrical field surrounding high-tension wires. I believe that hoists on military aircraft have a more stringent design spec than those developed for civil aircraft unless the hoist is specified for use on a specific helicopter and then the airframe manufacturer applies their specification requirements.
