I've read that the Titanic movie is incredibly accurate *for what we knew in 1997*. What elements of the movie are now out of date based on newer research?

Hi there!

Great question! Let me first begin that Cameron's "Titanic" is remarkably, painstakingly, accurate. It is a massive gift, so much so that I struggle to think of any film based on a historical event that is as well crafted and cared for (I suppose the opening scene to "Saving Private Ryan" would be another). There are slight little inaccuracies, tiny ones (for example, Rose holds up a post 1940s dime) but these are tiny oversights, not deliberate choices. As far as the event goes- what you see is what you would have seen had you been there. For example, there's a great shot of the bow sinking that shows the window to the chart room. If you look, you see the blueprints spread out on a desk. It's quick fly over shot- but Cameron still honors those tiny details. Amazing.

However, since 1997, new research and discoveries have dated Cameron's film- or at least thrown some of it into question. I'll address the two big ones for you.

The first we have definitive evidence for and that is Titanic's central propeller. In Cameron's film, we have this incredible shot of Titanic's props firing up, with the focus being on her four bladed central.

However, within the last ten years we discovered evidence- and within 5 years discovered a corroborating source- that Titanic didn't have a four bladed propeller, she had a three bladed one.

Since construction, and through 1997 and beyond, it was assumed that Titanic and Olympic were both designed mechanically identically (I need to stress mechanically here because while they were similar, they were not identical in construction or design). In 1911, Shipbuilder published an in depth expose on the construction of the first two Olympic class liners with this description-

The centre or turbine propeller, which is illustrated by Fig. 61, has four blades and is built solid of manganese bronze. The diameter in this case is 16 feet 6 inches’.

To add, Finance, Commerce, and Shipping published the same year-

The [Titanic’s] propelling machinery consists of the same combination of reciprocating engines and turbines as is fitted in the Olympic,

It was naturally assumed the first article was describing both sisters, but in reality- was only talking about Olympic. The second article does not mention the propellers specifically but seems to be referring to the entire mechanism. By the time of publication, Titanic was already launched and under construction- obviously there was no way to check, nor should they. The attention, after all, was on the more famous Olympic- biggest ship in the world, about to make her maiden voyage that June.

Evidence for the four bladed prop then grew as pictures of the new liners began to be printed. However, every picture you see of Titanic's propellers isn't Titanic- it's Olympic. There are no pictures of Titanic's propeller system, save this. What you are looking at is Titanic under construction with a propeller (highlighted) laying alongside her. We can't tell how many blades it has, or where it's intended to be. It may not even be for Titanic. It's just a propeller next to her in dry dock.

That was all the evidence we had, an article describing construction, until the mid 80's when we discovered Titanic's wreck. Unfortunately, examination of the stern gave us this- a totally buried central propeller system.

By 1997, based on the Shipbuilder article, the Finance article and the assumption that Olympic and Titanic were identical in their mechanical systems, and no proof from the wreck otherwise- Cameron made the safe and historically accepted choice to show Titanic with a four bladed central propeller.

It wasn't until 2008 that an unpublished notebook from Harland and Wolff was discovered that listed the propeller specifications and pitch for several vessels, including yard numbers 400 and 401- also known as Olympic and Titanic. Next to Titanic, under the "number of blades" heading, there is very clearly a number 3.

Suddenly, over a century of accepted fact was thrown into question- the HW notebook was astounding evidence, but it butted up directly with contemporary articles that stress the identical steering designs of the sisters. It wasn't until 2015 that a notebook belonging to engineer Stephen Pigott was discovered that gave us definitive proof to answer the mystery.

Olympic and Titanic's turbine systems weren't built in Belfast, they were built in Clydebank by John Brown and Co- and overseen by Stephen Pigott. His notebook, discovered about 5 years ago, has a list of the turbine systems for several ships built in 1910-1911- including the two White Star Liners. There, among projections of propeller pitch and resultant horsepower, states Titanic- 3 blades. Clear as day.

Boom! Mystery solved. The Pigott notebook corroborated the Harland and Wolf design and in 2015, we had the evidence that Titanic did indeed sail with a three bladed central propeller, not four as had always been assumed. Cameron's film, therefore, was wrong.

(Taking a quick side track here. This discovery also lead to the realization that White Star was using Olympic and Titanic as an experiment to discover which configuration of blade number + pitch lead to a more economically beneficial design in terms of coal consumption but also... speed. Remember, Titanic and Olympic weren't designed for speed or to speed, but WSL still wanted them to be able to cruise along as comfortably and quickly as they could. Olympic underwent a refit in 1913 for a three bladed propeller. Why? Because Titanic was beating Olympic's crossing time. For years, this was heralded as proof that Titanic was speeding and trying to beat a record. She wasn't, she was sailing normally- she simply had a different propeller system and design that White Star Line was experimenting with. Olympic was refitted with this design because of Titanic.)

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