On the Queen Mary (though it was much later than Titanic) the watertight door panel looked like the Titanic '97 one. I'd think that they wouldn't have changed the panel style drastically from 1912-1930
By an electrical switch mounted on the forward bridge wall, between the emergency telegraph and wheel. A door release switch and an indicator panel are two separate items.
<font color="#000066">Senator SMITH. I want my associates to know where this lever is, if a lever is used, or where the electric power is that locks these watertight compartments? Where is that operated from; what deck; what part of the boat?
Mr. PITMAN. The water-tight doors are operated from the bridge by a lever close to the wheel.
Senator SMITH. By whom?
Mr. PITMAN. By a lever close to the wheel.
Senator SMITH. I understand, but by whom?
Mr. PITMAN. Operated by the officer of the watch.
Senator BURTON. Do you know whether the water-tight doors were closed or not?
Mr. OLLIVER. The first officer closed the water-tight doors, sir.
Senator BURTON. When?
Mr. OLLIVER. On the bridge, just after she struck; and reported to the captain that they were closed. I heard that myself.
Senator BURTON. How did you know they were closed?
Mr. OLLIVER. Because Mr. Murdoch reported, and as I entered the bridge I saw him about the lever.
Senator BURTON. Did he have any way of telling whether they were closed or not?
Mr. OLLIVER. There is a lever on the bridge to close the water-tight doors, and he turned the lever over and closed them.
Senator BURTON. Was there an instrument there to show the doors as they closed? Did you ever see one of those instruments?
Mr. OLLIVER. No; I never saw one.
Senator BURTON. With little lights that burn up as each door closes, and then go out?
Mr. OLLIVER. No, sir.
Senator BURTON. There was no instrument like that on the Titanic?
Mr. OLLIVER. I did not see that.
Senator BURTON. Would you have seen it if it had been there?
Mr. OLLIVER. No doubt I would, sir.
Activation of the switch causes the friction clutch at each door to release the door. Gravity pulls the door down, with oil cataracts providing resistance to slow the rate of descent. There was no sensor to detect the door's closure; hence, no indicator panel.
By the way, I had to prove this to Jim Cameron's satisfaction after the movie had come out and that proved to be no easy (or happy) task.
A further consideration is that a rake of w/t doors - that on the tank tops I think - was float-activated and therefore presumably would bave closed anyway upon inundation, independent of the bridge overide switch.
Watertight doors on the ''Old Queens'' were operated naturally by bridge control and locally during ice routine.
All doors throughout sections of the working alleyway (Burma Road) were operated by holding a lever over on the bulkhead at the side of the door until the door was fully open. At this time a plate would rise up from the door track as the door slowly slid open, accompanied by the continuous ringing of a bell situated over the door with a red light flashing.
Safety always with these doors and at no time should anyone attempt to go through the door until fully open. Once your hand comes off of the lever, the door will automatically close.
Catering staff were the worst offenders, carrying trays and linen, taking their hands off of the lever and going through with the door only half open. These people were always in a hurry and despite the warnings, ignored the safety procedures.
It would be easy to trip over on the rising track plate and unless one was quick enough to recover, those doors would cut you in half like butter.
As usual, the deck department would have to clear up the mess.
I thought only the WTDs in the stokeholds were automatically controlled from the bridge on Titanic. As well as being equipped with a float trigger which closed the doors if water began to flood the boiler spaces.
The rest of Titanic's WTDs located in the corridors of the ship were operated by a hand cranked 'key' mechanism on the floor. Is this not correct?
And doors could be opened or closed from the deck above by using a similar 'key' to turn a fitting located on the corridor floor. Right?
I'm not an expert on Titanic or ever intend to be but hopefully some of what I write may be relevant.
The building of the Queen Mary commenced around some 20 years after Titanic and of course many improvements, like all ships, were made and installed.
If I remember rightly, there was at the back of the wheelhouse on the ''Mary'' the entire ships watertight door diagram and all the watertight doors were indicated by lights throughout the vessel when being operated.
At the commencement of fog and ice routine procedures, the bridge, after notification throughout the ship, would close all watertight doors. From here on in, all personnel would operate the doors as explained above, but doors will always end up shut regardless and until re-opened by bridge control.
Watertight doors throughout the vessel can also be cranked open manually if the hydraulics fail so perhaps this may give a little more info on the Titanic set-up.
I hope this helps,