A light unit has a strobe operated flash tube and a non-strobe peripheral lamp immediately beneath the flash tube; a switch can turn the unit off, operate either light or enable the pilot of an aircraft to signal the light unit to operate the flash tube or to turn off the flash tube and operate the non-strobe...http://www.google.ca/patents/US5559510?utm_source=gb-gplus-sharePatent US5559510 - Aircraft landing site indication and light
