Real Life Torpedo loading

[Blacklight]

I've often wondered this. When my friend was giving me the tour of the sub he worked on (the San Juan (688i class)). When we were in the torpedo room, it looked like the tubes could be loaded pretty quickly (to my civilian, completely non naval eyes). It looked like it was just a case of openening the hatch, having the boys just shove the torpedo in there, and closing up the hatch.
Why does loading a tube take so long ? What process do they have to go through ? :hmm:
Just curious.

[Bill Nichols]

Of course you have to hook up the cables for connecting the torpedo to the fire control system, and the wire for wire-guidance. After that you do checks to ensure everything is hooked-up correctly and the torpedo is healthy.

[Chock]

I presume there would have to be some coordination with the people controlling the boat's ballast too, since an ADCAP weighs around three and half thousand pounds, so I imagine it would affect the boat's trim when it was shifted into the tube, thus doing it slower would allow the compensation in trim to be more carefully controlled (this is just a guess by the way, but it seems logical).

Chock

[Sea Demon]

Originally Posted by Chock

I presume there would have to be some coordination with the people controlling the boat's ballast too, since an ADCAP weighs around three and half thousand pounds, so I imagine it would affect the boat's trim when it was shifted into the tube, thus doing it slower would allow the compensation in trim to be more carefully controlled (this is just a guess by the way, but it seems logical).

Chock

I hadn't thought of that. And it does bring up an interesting question. But if that is the case, then what happens to trim once the weapon is launched and you're suddenly lighter up front? :hmm:

[Sonoboy]

Originally Posted by Sea Demon

I hadn't thought of that. And it does bring up an interesting question. But if that is the case, then what happens to trim once the weapon is launched and you're suddenly lighter up front? :hmm:

Don't be near periscope depth?


Be careful with big weapons all
In this cramped torpedo room
Should one slip and fall "You killed us all!"
The torpedo says "KABOOM!"
:rotfl:

[Rip]

The weight of the fishmoving from in the rack to tube stowed isn't that big a deal as the distance moved forward isn't that far. Even 3ooo moved from bow to stern only effects trim under 5kts. It is accounted for and compensated by the COW. there is also the moving of water for flooding and draining the tubes. There are numerous weight effect evolutions every day. Each coordinated and compensated for. From pumping the **** tanks to making water.

The loading of weapoms into the tube also rquires hooking and unhooking starps and hydraulic rams the manipulate/secure the weapon not to mention needing to pivot the trays to allow for the slight outward angle of the tubes. A shapr weapons loading team can load one pretty fast though. But they always excersize a good dose of caution as is required by the procedures.

Definately a lot less back breaking than loading them without the hydraulic "rabbits" though.

[TopTorp '92]

Originally Posted by Blacklight

Why does loading a tube take so long ? What process do they have to go through ? :hmm:
Just curious.

We did loads/reloads in 8 min or less. It takes long depending on the number of team members present. Experience plays the decisive role.

Ordinance Document (OD) 44979 spells out the procedure.

During the tube loading procedure the torpedoman must remove the exploder safety screw. That screw is what prevents the warhead from arming while the torpedo sits anywhere outside the tube (like on the rack or somewhere on the pier.) The idea was to prevent the torpedo from arming in a hot-run situation. It sticks out by about 1/2'' or so. Failure to remove the screw will result in a sheered screw virtually impossible to remove by any allowable means AND it turns a mult-million dollar weapon into a dud. I've read and heard stories about a torpedoman using an electric drill on the exploder to remove the carcas. Highly illegal according to the OD 44979 and potentially suicidal for the submarine to do so. Do you REALLY want to create excessive vibrations in the exploder of a warhead? Didn't think so.

Once the torpedo has been tube loaded, the arming rod is kept in check by the inner walls of the tube. So, here too it is impossible for the exploder to arm while inside the tube.

Then the fire control team will test the torpedo communication link by applying power and following an additional OD 44979 procedure. Analog MK-48 took longer while digital ADCAP was/is faster (fewer moving parts.)

Top Torp