Carson nosed his plane down, his machine-gunner firing on the submarine. As it came into bombing position, he dropped a bomb which hit the vessel, and as it exploded two of the gun crew fell, apparently badly wounded. The U-boat cleared its decks and dived. Just as it plunged beneath the surface, another seaplane came into position and dropped two bombs. One exploded in the splash where the submarine plunged, and the second slightly forward of that point in the curving line of the descending boat. Four minutes later the submarine again came to the surface. But before Carson could get his plane in position for bombing, it again submerged, sliding beneath the waves stern foremost. Carson unloaded his bombs on the moving wake, and put back to the station for more ammunition. When he returned oil covered the water and a lone life preserver floated near the spot where the submarine went down. The value of coöperation between aircraft and vessels was strikingly demonstrated in the sinking of the U-boat called "Penmarch Pete," which was, according to reports received, destroyed by American seaplanes from the Ile Tudy Station and the U. S. destroyer _Stewart_, on April 28, 1918. Two planes left Ile Tudy that morning, one piloted by Ensign K. R. Smith, the other by Ensign R. H. Harrell, on convoy duty. Zigzagging along the coast nearly due west, at 11:30 o'clock they picked up a convoy of twenty ships heading south, six miles northeast of the Pointe de Penmarch. Heavy fog kept the planes at a low altitude and in the course of maneuvers about the convoy, a stream of air bubbles, denoting the wake of a submarine, was sighted by both planes. Smith descended close enough to the surface to distinguish a large oil patch. He dropped two bombs, the first being apparently a direct hit, and the second within ten feet of it. Dropping a phosphorus buoy to mark the location, Harrell sent down a correspondence buoy in the vicinity of the _Stewart_, then off the flank of the convoy. The _Stewart_ speeded to the spot, sighted a dark object in the water, and dropped a succession of depth-bombs. "These bombs were dropped so close to the submarine, one on each side and within fifty feet of it, and the force of the explosion was so great," reported Lieutenant Commander Haislip, her commanding officer, "that it seems impossible that the submarine could have survived." For days there rose to the surface quantities of oil, which spread for miles down the coast. The U-boat was later identified as "Penmarch Pete," which had operated off the Pointe for months, and had destroyed over 100,000 tons of shipping. Working with the British in the early stages of participation, our aviators made numerous flights over the North Sea, flying as far as the German coast. One of the first lost in action, Ensign Albert D. Sturtevant, of Washington, a Yale man, was second pilot of a machine that was attacked by ten German planes. Fighting against overwhelming odds, he went down in flames.