Tenbrook's character died when four Japanese float planes surprised the beached PT-34 in the aftermath of a torpedo run on enemy warships off the Philippine Islands of Cebu. Although I don't know for sure, it's possible that Larsen is the fictionalized name in the film for Chief Commissary Steward Willard J. Reynolds.
During the night action of April 8-9, 1942, Chief Reynolds manned one of the twin 50-cal. machine gun on the real PT-34. He was hit by shrapnel in the neck and shoulder as he fired his guns into a searchlight from the Imperial Japanese Navy cruiser Kuma that had illuminated the motor torpedo boat.
The Navy's official account of the PT boats in World War II, At Close Quarters: PT Boats in the United States Navy by Captain John D. Bulkeley, Jr., USNR (Retired)* continues the account of the death of Chief Reynolds and the sinking of the PT-34:
"WE COULD NO LONGER FIGHT" -- (Boat captain Lieutenant (Junior Grade)) Kelly tried to take the 34 into Cebu City before daylight to get medical aid for Reynolds. But he had only a large-scale chart, useless for navigating the channel. He idled in, and just when his soundings told him that he was in 3 fathoms, his boat ground to a stop on a coral pinnacle. He sent his executive officer, Ens. Iliff D. Richardson, USNR, ashore in a dinghy to find a tug for the 34 and a doctor for Reynolds. By daylight Kelly was able to rock the boat free. His center propeller and strut were damaged, but he was able to proceed into the channel on two engines.Chief Reynolds was the first of 18 food service rates (one chief commissary steward, 15 ship's cooks, one baker and one steward's mate) to die in the service of the World War II U.S. Navy motor torpedo boat squadrons. Like the June 2005 death of Seabee Culinary Specialist First Class Regina R. Clark in Operation Iraqi Freedom, it's a reminder that the cooks and bakers are just as vulnerable to enemy action as other service men and women.
"Under ordinary conditions," he said, "it would have been considered suicidal to have been operating in this area after daylight. However, the Army authorities had assured us of air cover and given us the assigned radio frequencies of the planes. These planes were scheduled to arrive that morning from Australia to form an escort for coastal steamers due to leave Cebu the next day carrying food for Corregidor. The radio of the PT 34 had been rendered inoperable during the previous night's engagement. However, I had every confidence that the planes would be there having seen a copy of the dispatch concerning them the night before.
"Shortly after 0800 a bomb landed close off the PT 34's port bow. We had not heard any planes due to the noise of our engines. Four Jap float planes were seen to be diving on us out of the sun, the first already having dropped its bomb. The PT 34's amidship .50 cal. turrets were already manned and began firing immediately. The port bow .30 cal. Lewis machine-gun was blown off its stand by the first bomb's blast. The starboard bow .30 caliber was manned immediately by the quartermaster and I took the wheel. During the next 15 minutes eight bombs were dropped on the PT 34. All were near misses (under 25 yards). The planes dove from about 500 feet altitude strafing as they came out of the sun. The first run killed the starboard .50 caliber gunner and disabled the gun. The next two runs knocked out the port .50 cal. turret. On the third run the quartermaster, Ross, hit one of the float planes causing it to smoke heavily. It was presumed to have crashed (although it was not seen to hit the water) since it was not seen during any subsequent attack. On the next run Ross was hit and his gun disabled.
"Since the PT 34 was in a narrow channel and only had two engines, maneuvering was extremely difficult. During the succeeding runs the boat was riddled with .30 cal. holes although it received no bomb hits. Chief Torpedoman Martino, who was acting as Executive Officer, rendered first aid to the crew and kept me informed of our damage. When I received word that the engine room was flooded with about 3 feet of water and the engines could not last much longer, it was decided to beach the boat since we could no longer fight."
Kelly beached his boat on Cauit Island and got his crew ashore. David W. Harris, TM2c, who had been in the starboard turret, was dead. Reynolds had been wounded again, this time fatally. Albert P. Ross, QM1c, who had hit the enemy plane; John Martino, CTM, and Velt F. Hunter, CMM, were wounded.
At 1230 the three planes returned while salvage operations were underway and bombed and strafed the 34 again. This time they set the boat afire, and it burned and exploded on the beach at Cauit Island, southern approach to Cebu City.
Chief Reynolds was posthumously awarded the Silver Star for gallantry in action.
*Bulkeley commanded both the squadron and PT-41 during the attack on the IJN Kuma. He was awarded the Congressional Medal of Honor for his service in command of the squadron.