Titanic's hull

[Noel F. Jones]

According to The Shipbuilder (reprint), page 19:

The keel of each vessel is formed by a single thickness of plating 1-1/2 inch thick and a flat bar 19-1/2 inches wide by 3 inches thick

Fig.15 looking down-slip (apparently) shows a hydraulic riveter working on a fabricated I-beam periodically reinforced with angle beam. There are no lightening holes in evidence.

Fig.23 in contrast is a more distant view, looking up-slip (apparently), of (apparently) the same member and in which vertically aspected oval lightening holes are very evident.

I find it unclear as to where these views were in relation to the vessel's length but these disparities suggest the I-beam was lightened over some considerable portion of its length, probably towards the extremities of the vessel - or would this be inconsistent with the fulfilment of the 'equivalent girder'?

Furthermore, the engine elevations show an augment of height in way of the engine beds.

Noel

 

[Scott R. Andrews]

Noel,

Fig. 15 is taken looking aft along the keel on the port side. The camera is positioned approximately beneath where the forward LP cylinder will stand. Regarding your observation about the change in depth of the bottom structure beneath the reciprocating engine room, you will note the dropping off of the top flange as the keel progresses aft into the area to be occupied by the turbine engine room. The same thing would be visible going forward just behind where the camera is stationed. The angles being riveted to the vertical plate are the flanges to which will be attached the "floors", the transverse web frames which join the bottom shell with the tank top. Open rivet holes may be seen in the flanges just aft of where the riveter is being used.

Fig. 23 is taken looking forward from the after starboard side towards forward port. The curved line of the blocks indicates the place where the stern frame will rest once set in place. The portion of the vertical keel plate you see is aft of frame 125 Aft, the aftermost end of the double bottom structure. The portion forward of this right on through frame 112 Forward has no lightening holes and is caulked watertight to divide the bottom within the margin plates into port and starboard tanks, which are further subdivided transversely by numerous watertight floors. Sam Halpern's excellent article "Titanic's Hidden Deck" will help to clarify the subdivision of the tanks within the double bottom:
https://www.encyclopedia-titanica.org/articles/halpern_deck.pdf

Regards,

Scott Andrews

 

[Scott R. Andrews]

Noel,

Looking at Sam's article, I have to correct myself on one point. Tank No.15, the farthest aft within the bottom structure, is not divided into port and starboard halves, so it is likely that the presence of lightening holes in the after end of the vertical keel plate continues on up to WTB "O" at frame 111 Aft.

Regards,
Scott Andrews