The caption reads 'Billowing smoke marks the end of the ammunition ship SS Mary Luckenbach, seen from the deck of the escort carrier HMS Avenger (D14), during convoy PQ 18 to Russia, 13 September 1942. The ship was attacked by several German aircraft, and was hit by an aerial torpedo. The impact of the torpedo struck the ship's cargo of 1,000 tons of TNT. The explosion was so violent the ship was basically vaporized along with the entire crew. The last known location of the ship was 75 degrees north, 10 degrees east.'

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