Lightning Protection Guidelines For Aerospace Vehicles PDF Download

Alternative approaches in lightning protection of diverting a direct lightning strike to some distance away, or shielding sensitive equipment to withstand a direct stroke can be usefully combined for maximum protection. Lightning strokes to diversionary rods or towers still leave intense transient magnetic fields to contend with, as well as possible large ground currents in control cables. Shielding of all conductors and associated 'black boxes' of equipment is theoretically possible if resistance of cable sheaths and connector joints can be kept low enough. A possible combination approach in a ground installation is to "invite" nearby strokes to a central high point over a 'bird cage' wire assembly surrounding the launching system thus guiding the lightning current symmetrically so that the magnetic fields inside cancel to approach in effectiveness a complete "Faraday cage" with reasonable feasibility as to practicality and cost, for most cases of lightning to ground strokes which are nearly vertical. Slanting strokes or nearby strokes and intense EM waves would require some horizontal interconnecting wires as well. In cases of dry sandy terrain improved additional lightning protection may be necessary even for buried cables as indicated in illustrative test demonstrations.