Overview of FTR escape trunk.

Escape I.

a-See that overhead hatch is securely dogged. Check blow valve in For'd. Torp. Room & vent valve in escape trunk which are normally closed.

b- Men enter escape trunk with escape appliances adjusted to body (first group to enter take ascending line, buoy and suitable metal object to signal evacuation of trunk).

c- Close lower hatch.

d- Flood trunk as rapidly as possible through flood valve without excessive discomfort to occupants.

e- See II(a) for adjustment of air bubble.

f- If there is any physical evidence of excess CO2 during flooding, adjust mouthpiece & nose clip of escape appliance, charge it every four or five minutes with oxygen & breath through appliance

Escape II.

a- Flood trunk until water reaches top of door equalize inside and outside pressures by admitting air through escape trunk blow valve (divers connections), or, by cracking door, depending on depth.

b- Adjust mouthpieces and nose clips.

c- Charge escape appliances. If they were used for breathing purposes during flooding, recharge them.

d- Crack door.

Escape III.

a- Open door

b- Stream the escape buoy

c- When buoy is waterborne, make ascending line fast to padeye on outside of escape trunk. Cut the inboard end short so that it will be entirely clear of the door.

d- Stow reel and all remaining line well outside escape trunk to prevent fouling watertight door.

Escape IV.

a- Men leave trunk one at a time; Last man to leave trunk raps on door frame with object to signal that escape trunk is cleared.

*b- Last man to leave trunk close & dog door if practicable.

c- If door was not closed by last man, close trunk door with inboard closing device in torpedo room.

*d- Blow water overboard thru flood valve if possible. Close valve, open drain valve to blow remaining water to bilge.

e- If impracticable to blow trunk overboard thru flood valve, drain all water to bilge by closing flood valve & opening drain valve in torpedo room. Open inboard vent only if water flow slows down, indicating trunk pressure is lost.

f- Close drain valve & vent & blow valves in torpedo room.

*NOTE: Trunk cannot be blown outboard unless door has been dogged-operation "D".

Escape V.


(a) See that upper hatch of For'd. Escape Trunk is dogged tightly.

(b) Strike down any floatable material that might foul door closing.

(c) Set oxygen regulator to 60 pounds above sea pressure as registered on gauges (in For'd. Torp. Room and Control Room) before flooding trunk.

(d) When buoy has been streamed and secured, be sure that neither the streamed line nor the inboard cut end can in any way foul the door gear or knife edge.


Escape Aft Torpedo Room.

1- Close watertight door on torpedo room bulkhead see that overhead escape hatch & torp. trunk hatch are securely dogged; fit hatch skirt.

2- Turn off all except pressure proof electric light fixture. If ships current is dead, light emergency light overhead near trunk.

3- Pass out lung to each man.

4- Flood compartment as quickly as possible, remove bonnets from trim & W.R.T. tank drain valves. Remove manhole cover from W.R.T. tank, equalize pressure in torpedo tubes; open torpedo tube muzzle doors; break interlocks on Torp. Tube Drain Valves; open Torp. Tube Drain Valves; Open torpedo tube inboard vents.

5- When pressure has risen to that corresponding to depth of submergence, as indicated by caisson gauge and by cessation of upward movement of water level in compartment, open hatch.

6- Stream ascending line until buoy watches and then secure line inside the compartment.

7- Men escape one at a time up the ascending line, proceeding upward at a steady hand over hand pace.

In flooding the compartment it should be noted that the height of the water in the compartment upon equalization will depend upon the depth of submergence. At shallow depth the water will cease to rise when it is still clear of the trunk, and this excess "Bubble" will vent out and be replaced by water when the hatch is opened. At deep depths, maintain bubble, if practicable, buy bleeding air into compartment.


Before proceeding with escape instructions for flooding outlined above, stow all false target shells into a torpedo tube and secure breech door.


Escape Conning Tower.

Conning Tower to be used for escape purposes only in emergency when Control Room compartment or compartments both For'd and Aft of the Control Room compartment are flooded.

To accomplish escape from Conning Tower proceed as follows:

(A) In event Control Room compartment is flooded, men shall adjust escape appliances and charge from oxygen manifold, then release pressure of dogs on lower hatch to crack seal of hatch and permit flooding of Conning Tower.
(1) When pressure in Conning Tower is equalized to sea pressure open upper hatch. Stream escape buoy and ascending line, and escape leaving one at a time following each other as soon as practical.

(B) In event compartments both For'd. and Aft of Control Room compartment are flooded, Control Room compartment shall be flooded by means of sea chests or an alternate means of equalizing pressure can be accomplished by bleeding air into compartment from air pressure valve in control room. Then proceed with escape similar to that outlined in paragraph (A)(1).

(C) CAUTION:- Upper hatch should not be opened for escape purposes until hatch dogs have been eased off slightly and hatch cracked, with dogs still in such position as to prevent hatch from opening fully, permitting venting of air and completely flooding Conning Tower; or bolts securing periscope stuffing tubes may be eased off to accomplish venting and flooding as an alternate method in lieu of cracking upper hatch.


Submarine Rescue Chamber

For detailed description and method of operation see booklet entitled the "Submarine Rescue Chamber", issued to the Submarine Force, U.S. Fleet.

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