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Smoke Signals
Smoke Signals
Japan Maritime Self-Defense Force aviators light night-time smoke signals as part of their mandatory, semi-annual Life-Saving Survival Training aboard Marine Corps Air Station Iwakuni, Japan, Jan. 28, 2014. Night-time smoke signals use grey smoke with a flashing red light, while day-time smoke signals are bright red in color. The signals burn for approximately 70 seconds.
(U.S. Marine Corps photo by Lance Cpl. D. A. Walters/Released). Original public domain image from Flickr
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