Texas City Disaster - Explosions

Explosions

The 38% ammonium nitrate, used as fertilizer and in high explosives, was manufactured in Nebraska and Iowa and shipped to Texas City by rail before being loaded on the Grandcamp.

It was manufactured in a patented process, mixed with clay, petrolatum, rosin and paraffin to avoid moisture caking. It was also packaged in paper sacks, then transported and stored at temperatures that increased its chemical activity. Longshoremen reported the bags were warm to the touch prior to loading.

Around 8:00 a.m., smoke was spotted in the cargo hold of the Grandcamp while it was still moored at its dock. Over the next hour, attempts to put out the fire or put it under control failed as a red glow returned after each effort to douse the fire.

Shortly before 9:00 a.m., the captain ordered his men to steam the hold, a firefighting method where steam is piped in to put out fires in the hope of preserving the cargo. Meanwhile, the fire had attracted a crowd of spectators along the shoreline, who believed they were a safe distance away. Spectators noted that the water around the docked ship was already boiling from the heat, and the splashing water touching the hull of the ship was vaporized into steam. The cargo hold and deck began to bulge as the pressure of the steam increased inside.

At 9:12 a.m., the ammonium nitrate reached an explosive threshold and the vessel then detonated, causing great destruction and damage throughout the port. The tremendous blast sent a 15-foot (4.5 m) wave that was detectable nearly 100 miles (160 km) off the Texas shoreline. The blast leveled nearly 1,000 buildings on land. The Grandcamp explosion destroyed the Monsanto Chemical Company plant and resulted in ignition of refineries and chemical tanks on the waterfront. Falling bales of burning twine added to the damage while the Grandcamp's anchor was hurled across the city. Sightseeing airplanes flying nearby had their wings shorn off, forcing them out of the sky. Ten miles away, people in Galveston were forced to their knees; windows were shattered in Houston, Texas, 40 miles (60 km) away. People felt the shock 100 miles away in Louisiana. The explosion blew almost 6,350 tons of the ship's steel into the air, some at supersonic speed. Official casualty estimates came to a total of 567, including all the crewmen that remained onboard the Grandcamp, but many victims were burned to ashes or blown to bits, and the official total is believed to be an undercount. All but one member of the Texas City volunteer fire department were killed in the initial explosion on the docks while fighting the shipboard fire, and with the fires raging, first responders from other areas were initially unable to reach the site of the disaster.

The first explosion ignited ammonium nitrate in the nearby cargo ship High Flyer. The crews spent hours attempting to cut the High Flyer free from its anchor and other obstacles, but without success. After smoke had been pouring out of its hold for over five hours, and about 15 hours after the explosions aboard the Grandcamp, the High Flyer blew up demolishing the nearby SS Wilson B. Keene, killing at least two more people and increasing the damage to the port and other ships with more shrapnel and fire. One of the propellers on the High Flyer was blown off, and found almost a mile inland; it is now part of a memorial park, and sits near the anchor of the Grandcamp. The propeller is cracked in several places, and one of the blades has a large piece missing from it, a mute testament to the destruction that took place that day.