I recently took a trip to New Orleans. For a city that is technically 100 miles from the Gulf of Mexico along the Mississippi River, it is a very busy port and has been since the early days of the western exploration. A landmark in New Orleans today is the tourist steamboat Natchez. This steam powered paddle wheel ship cruises up and down the Mississippi with decks full of tourists to show how people traveled back in the early 1800s. Interestingly enough, this type of ship was the setting of one of the biggest disasters in U.S. history, and the cause was a boiler explosion.  

Roughly 1,800 passengers died when the Sultana’s boilers blew apart in 1865. For reference, 1,500 people died when the Titanic sunk. The reason this event isn’t better known in American history is likely because it happened shortly after the Civil War ended. Around 600,000 soldiers died in the Civil War, so tragedy didn’t have the same headline value it would have had in peacetime.  

The other major headline that overshadowed the Sultana disaster is that President Lincoln was murdered 12 days before. His assassin John Wilkes Booth was executed the day before the boat sunk. We also didn’t have the lightning-fast media response we do now. 

According to a PBS episode of “History Detectives,” the Sultana was commissioned to take former prisoners of the Confederate army back to the North. Before the Sultana arrived in Vicksburg, Miss., one of the boilers sprang a leak, and it barely limped in to port. Upon arrival, R.G. Taylor, the ship’s boilermaker, diagnosed a fix that would take three days. This would mean they would miss their awaiting Union army passengers. Captain J. Cass Mason told Taylor to just patch the boiler up so they could keep going. This wasn’t the best time to fix the boilers (does this conversation sound familiar to you?).
The Sultana started to load passengers in Vicksburg on April 24, 1865. The boat was certified for less than 400 travelers. An estimated 2,400 people were in line to board. This was brought to the attention of Reuben Hatch, the quartermaster of Vicksburg and port authority; he was by most accounts a very corrupt man. 

Hatch knew that the ship was dangerously over capacity with passengers. It is alleged that Hatch was taking a kickback from Captain Mason per head loaded on the Sultana. The U.S. government was giving five dollars per enlisted man to transport back north. 

The last known photo of the Sultana looked as if passengers had been poured out of a hose on the top of the ship. They had to use additional supports to keep the top deck from collapsing. The passengers, many of whom had survived war camps in the south, were more than willing to crowd on to get home.  
It would be interesting to see a parallel universe where Lincoln wasn’t assassinated. Many accounts, including the PBS special, detail a complex web of political favoritism that kept Quartermaster Reuben Hatch in his position. Hatch had a military career full of graft. He was also very well connected. His brother, Ozias Hatch, was the Illinois secretary of state. Ozias effectively lobbied President Lincoln and other influential politicians to keep Reuben not only out of court, but to get a promotion before the Sultana event. At one point, Lincoln and General Ulysses Grant both wrote letters to Reuben Hatch’s direct superiors to keep him appointed.  

The four boilers on the Sultana were coal fired steam vessels. They were a horizontal fire tube design. Under normal conditions, the round chambers would be completely full of water. A theory for the boiler explosion is that the vessels were leaking, and the top heavy ship was swaying left and right enough to create dry fired hot spots on the high side of the exchangers. Since one of the boilers was already in a weakened state, these conditions would be very stressful on the exchangers. A sudden drop in pressure could cause the rest of the water in the boilers to flash to steam. Water expands by a factor of 1,600 when it turns to steam. Boiler explosions also threw burning coal in all directions, which is why Sultana burned after the boilers ruptured.  

In my travels as a manufacturer’s rep, I occasionally run into finicky boiler safeties and red tape with inspectors. The reason that ASME vessel ratings, pressure switches, relief valves, low water cut off switches and manual reset high limits exist isn’t to overburden contractors with additional components. Any of the safeties listed above could have prevented the Sultana disaster. While I sometimes have to argue that you don’t really need a low water cut off and a flow switch on the same boiler, overall safeties aren’t the problem. Modern safeties are the reason boiler explosions aren’t commonplace like they were in the 1800s and 1900s.  

Another lesson learned from the Sultana is that boiler mechanics know more than boiler owners. There are cases where building owners are under a lot of pressure to get boilers up and running against their best interests. As a contractor, you can walk away from those jobs. If you are faced with the choice of putting a boiler back in service when doing so would be potentially dangerous or losing a customer, that is an account that isn’t worth keeping. How would you feel if you had been the last boiler guy in the Sultana before it exploded?  

The Sultana explosion threw roughly 2,400 people, mostly former Union soldiers, into the cold Mississippi. In a true testament to southern hospitality, the very people who may have been shot at by the passengers of the Sultana in the years prior risked their lives to pull survivors to safety.  The southerners near the Sultana could have just watched the Union soldiers drown or burn. Instead they helped, according to an NPR article published in April, "The Shipwreck That Led Confederate Veterans To Risk All For Union Lives."   

The Sultana isn’t widely remembered, but it is actually one of the biggest disasters in American history, and possibly the single most deadly boiler explosion. Boiler safeties were developed because of events like this. Jumping a boiler safety to get it back in service could end up being a jump back to 1865. 

Max Rohr has worked in the hydronics and solar industry for 10 years in the installation, sales and marketing sectors. Rohr is a LEED Green Associate and is Radiant Professional Alliance’s (RPA) Education Committee chairman. He can be reached at max.rohr@mac.com and @maxjrohr.com.