Set in the afterbody of the torpedo is a socket in which is a spindle with a square male shank for setting the depth mechanism. This spindle in the torpedo is engaged by a spindle which has a squared socket wrench at its lower end, this socket being suspended flexibly, in pendulum fashion, and passing down into the tube from the depth setting mechanism attached on the outer side of the barrel. The socket is moved down into the tube to engage the spindle in the torpedo, and raised or retracted, by means of the engaging lever. When the socket has engaged the spindle in the torpedo, the depth mechanism is set by means of the depth setting crank which can be turned only when the spindle is engaged in the socket. One revolution of the depth setting crank equals two feet of depth setting.

The position of the depth setting mechanism in relation to the other operating mechanisms is shown in Figure 147, a view of the inboard breech end of the torpedo tube. A close up view of the engaging lever and the hand crank for operating the depth setting mechanism as attached on the tube is shown in Figure 148. In this view, the depth setting

Figure 150 shows the engaging lever moved to spindle out position, releasing the interlocking bolt and also the lug on the collar of the interlocking sleeve.

The closely interrelated operation of the interlocking mechanism described in Chapter 4 is emphasized here when it is understood that the depth setting mechanism has its own individual connection with the interlocking mechanism, as has every other unit of the operating mechanism, to prevent improper or unintentional firing of the tube. That is the function of this interlock bolt shown in the three illustrations, Figures 148, 149, and 150. The interlocking bolt is also shown in the other views which follow.

The depth setting mechanism, assembled, but detached from the barrel, is shown in Figure 151. Here the interlock bolt is shown in locked position, the engaging lever is in spindle out position, and the hand crank is locked by the detent plunger which passes through the extension of the housing between the setting lever and the hand crank, and is engaged by a lug on the setting lever when the lever is in spindle out position. When the setting lever is moved to spindle in position, the lug on the lever disengages the detent plunger so it is released from the slot in the detent wheel on the hand crank, as

Figure 151 Depth setting mechanism assembled, but detached from barrel. (A) Index dial; (B) Interlock bolt; (C) Decent plunger engaging decent wheel to lock hand crank; (D) Engaging and disengaging lever; (E) Hand crank for rotating spindle to set depth.

shown in Figure 152, thereby unlocking the hand crank for operating the depth setting mechanism.

Another view, from the side, showing the setting lever in spindle out position, and the interlock bolt in locked position to prevent moving the setting lever after the spindle has been disengaged from the socket in the torpedo and retracted from the tube, is shown in Figure 153. It will be noticed that the bolt has been moved back so the lug on the setting lever can not enter the opening in the interlock bolt, and the detent plunger is engaging the detent wheel on the hand crank.

Figure 154 shows the interlock bolt moved forward to disengage the setting lever, and Figure 155 shows the setting lever moved to spindle in position, the lug engaging the opening in the interlock bolt,

Figure 152 Turning hand crank after (A) Slot in detent wheel on (B) Hand crank has been released by (C) Detent plunger when (D) Lug on engaging and disengaging lever engages interlock bolt as (E) Lever is moved to "Spindle In" position.

thereby locking the interlocking mechanism until the bolt is released by moving the setting lever back to spindle out position.

Figure 156 gives a worm's eye view of the depth setting mechanism, looking up into the housing from below, to show the engaging socket on the spindle in the down position, as it would be when engaging the spindle in the torpedo to set the depth mechanism.

In Figure 157, also a worm's eye view, the engaging socket is shown up, in the position in which it would be when retracted from the tube after setting the depth mechanism in the torpedo.

Figure 158 is a break-away view showing the interior of the housing, giving a better idea of the action of the mechanism.

Figure 156 Worm's eye view of depth setting mechanism showing spindle with socket down in position to engage socket in torpedo.

The parts of the depth setting mechanism, disassembled, are shown in Figures 159 and 160, Figure 159 showing the parts that are assembled in the housing horizontally, and Figure 160 those parts that are assembled in the housing vertically.

As the engaging lever is moved to spindle out or to spindle in position, the shaft attached to the

Figure 157 Same as Figure 156, but showing spindle up, or in retracted position.

setting lever operates a fork (see Figures 156 and 157) which raises or lowers the sleeve in which the engaging socket is secured by means of a rivet pin. The socket lies in a vertical plane through the tube axis within a tolerance of 0.015 of an inch to permit self-alignment with the depth setting spindle in the torpedo. Engagement of the socket with the spindle

Rotation of the depth setting socket is accomplished by means of the hand crank attached to the shaft, which turns the sleeve by means of the bevel gears keyed to the sleeve and the bevel pinion attached to the shaft. This is shown in Figure 158.

An index dial (see Figure 151) graduated in feet from 0 to 50, is driven from the depth setting shaft, operated by the hand crank. Two forms of index dials are used, one, as shown in Figure 151, having the graduations on the flat top surface so as to be read from above looking down. This form of dial is used for middle and lower bow tubes and for lower stern tubes. The other form of dial, used for upper bow and stern tubes, has the graduations on the outer circumference of the dial so as to be read from the side instead of from the top of the dial.

When the engaging and disengaging lever is in the out position, the lug on the setting lever blocks the detent plunger, preventing it from moving out of the slot in the detent wheel on the hand crank, thereby locking the hand crank.

Before loading a torpedo into the tube, the depth index dials, on both the torpedo and the depth setting mechanism on the tube, should be set at the 10-foot setting.

When the engaging and disengaging lever is in the spindle out position, the lug on the lever is clear of the sliding bolt, thereby releasing the lug on the collar of the interlocking sleeve, and permitting the firing interlocking lever to be moved to "Tube Ready to Fire" position. In this position, the body of the sliding interlock bolt is in the way of the lug on the engaging and disengaging lever, preventing it from being moved to the spindle in position.

It is easily seen that it would be an impossibility to turn the submarine so the tubes would be aimed directly at the target each time a torpedo was to

The gyro mechanism in the torpedo, in combination with the vertical steering engine through the vertical rudders, will bring the torpedo around to whatever angle has been determined it should take

Figure 162 Operating engaging lever and release button.

The gyro mechanism in the torpedo must be set for each shot, and the setting must be done in the last moments before firing. For that purpose, the gyro setting mechanism is included as one of the operating units on the outside of the barrel, with a spindle projecting through into the barrel and engaging a socket connected with the gyro mechanism in the afterbody of the torpedo.

The gyro setting mechanism, as installed in

Figure 163 Gyro setting spindle and retracting mechanism, complete assembly, detached from tube. (A) Engaging lever; (B) Release button; (C) Retraction lever; (D) Indicator for showing spindle in or out; (E) Spindle housing; (F) Indicator switch housing; (G) Drive shaft which operates gears to rotate spindle for setting gyro angle.

There are variations in the arrangements of the gyro setting mechanisms in different submarines, The system described here is strictly applicable to the installations in SS198 and up, only. For other installations, refer to O.P. 586 (SS170 and up) or O.P. 281 (SS167-169).

Figure 164 The reverse side of the gyro setting mechanism, showing the flange which attaches to the barrel. (A) Setting lever and latch; (B) Retraction lever, connected by ratchet, chain, and sprocket to the stop rod for retracting the spindle automatically when the firing mechanism is set in action; (C) Spindle, in the in or engaged position.

Figure 162 shows the engaging and disengaging lever, one hand pressing the release button, the other hand moving the lever, having pressed the latch in the upper part of the lever to unlock it.

Figure 163 is a close-up view of the engaging and

Figure 165 Close-up view of the gyro setting spindle housing, reverse side, showing the spindle in the in or engaged position.

disengaging lever and the spindle housing, detached from the barrel. Figure 164 is a view from the other side, the side which attaches to the barrel, showing the spindle which projects into the tube to engage the socket in the torpedo, also the retraction lever which is attached by gearing to the stop rod which raises the stop bolt, so that the gyro setting spindle is automatically retracted at the same time as the stop bolt, after the firing key has been pressed and the firing mechanism is set in operation, as explained in Chapter 5 on the firing mechanism.

A close-up view of the spindle in the in or engaged position is shown in Figure 165, and one showing the spindle in the out or retracted position is shown in Figure 166.

The parts of the gyro setting mechanism, disassembled, and arranged as nearly as possible in the order and the position in which they would be

The gyro setting mechanism, while directly connected as one unit, in reality consists of two distinct units, one for moving the spindle into or out of the socket (for engaging or disengaging the spindle), the other unit for rotating the spindle to set the mechanism in the torpedo after the spindle has been engaged in the socket on the torpedo.

The spindle is engaged in the socket of the torpedo by means of the engaging lever (D in Figure 161, this being connected to the clutch fork shaft which extends down to the spindle housing. In the spindle housing, attached to the lower end of the

Figure 166 (at right) Close-up view of gyro setting spindle in the out or retracted position.

shaft is a clutch fork the arms of which engage the spindle sleeve, to which the spindle is attached with a certain degree of looseness to allow flexibility for engaging the socket in the torpedo.

As the engaging lever is moved to engage or to retract the spindle, the position in or out is shown by means of an indicator plate attached to the shaft, and an arrow on a pointer plate (see I in Figure 161, also D in Figure 163).

The gyro setting spindle has a square shank at the end which engages the socket in the torpedo for setting the gyro mechanism. This squared shank of the spindle must line up with the socket in the torpedo-that is, the sides of the squares on both the spindle shank and the socket must be parallel. The spindle, as previously stated, is mounted in the sleeve with a slight looseness, and is centered in the sleeve by means of a spring, which facilitates engaging the

When a torpedo is loaded into the tube, both the torpedo gyro and the setting spindle should be set at zero to insure lining up of the spindle and the socket. (This applies except when it is desired to check the actual setting on the torpedo at some other angle than zero, and a torpedo is withdrawn from the tube for that purpose.) At the zero setting on both the spindle and the socket, the sides of the squares on both the spindle and the socket are horizontal and vertical.

If it is found hard to enter a spindle into the socket of the torpedo, the spindle may be rotated slightly in either direction by means of the hand drive of the gyro setting indicator regulator.

The spindle sleeve passes through a stuffing box to enter the tube. The spring pressure on the chevron-type sealing rings in this stuffing box (parts 15, 16 and 17 of Figure 167) is not adjustable, and has been held to the minimum so as not to bind the spindle sleeve. Split sealing rings should not be used. Before new rings are installed, they should be soaked in hot neats-foot oil. After new rings are installed they should be exercised by rotating the setting spindle sleeve for 20 minutes, occasionally also working

A stuffing box drain is provided in the housing base to drain off small quantities of water which may leak past the stuffing box before it can do any damage. This drain must not be obstructed in any way; otherwise any leakage past the stuffing box will back up into the tube unit housing, and will corrode the working parts.

When engaging the spindle, the operating handle is grasped, as shown in Figure 162, and the latch or handle lock release, which is mounted in the top of the handle, is pressed down to unlatch the handle from the handle lever bracket. Pressing the latch or handle lock release acts to pull down the handle lock bolt. The handle is then turned to the in position shown on the indicator plate (D in Figure 163). When the handle has been moved to this position, the shaft bolt release button (G in Figure 161) is pressed to disengage the handle shaft bolt from the handle, and to engage it with the mating toe on the retracting lever (H in Figure 161). Holding the shaft bolt release button in, the operating handle is returned to its latched position, as shown at F in Figure 161.

The foregoing process is reversed to retract or disengage the spindle manually. The operating handle

or lever is unlatched from its latched position and rotated until the handle shaft bolt snaps into engagement with it while releasing itself from the retracting lever. The operating handle is their returned to its latched position, carrying with it the handle shaft, setting spindle, and all connecting parts.

For retracting the spindle automatically, the disengaging or retracting lever is connected, by means of a sprocket and chain, to the stop rod which also retracts the torpedo stop bolt. The stop rod is connected to the piston of the stop cylinder as described in Chapter 5 on the firing mechanism. As the firing key is pressed, admitting air from the ship's service line through the stop cylinder valve to the stop cylinder, the piston of the stop cylinder, to which the stop rod is connected, moves to contact the piston of the pilot valve which releases the air to open the firing valve. As the piston of the stop cylinder moves, it draws the stop rod with it, thus retracting, first, the gyro, setting, spindle and, next, the stop bolt, before venting the fixing valve.

When the tube has, been fired, the stop rod and the gyro spindle retraction slide are returned to their original positions by the stop rod spring, carrying with them the intermediary multiplying lever and the retracting lever. The wide upper slot in the clutch cam permits this to be done without throwing the gyro setting spindle to its in or engaged position,

Figure 171 Operator at gyro setting indicator-regulator.

To reassemble, the foregoing process is reversed. It will be noticed that there are four .04 inch chamfered sections, each .25 inch long, at the horizontal and vertical center lines on the inner circumference or periphery of the threaded collar upon which the cap screws. The spindle sleeve should be entered with its keyways lined up with either pair of these chamfered sections. In this way, the spindle will be squared up so as to enter the setting socket of a torpedo with the gyro set at 0 degrees or any multiple of 1 1/4 degrees, since one turn of the spindle equals 5 degrees of gyro setting.

An indicator switch ("micro" type), D in Figure 168, is mounted in a housing, F in Figure 168, which in turn is bolted to the setting spindle housing. The switch is of the "normally open" type and is closed to light an indicating lamp by the action of a cam on the clutch fork, M in Figure 168, and the lever, L in the same figure, when the setting spindle is thrown to the "In" position.

Basic and spread gyro angles are set by the operation of the gyro setting indicator-regulator. See NAVORD. O.D. 2585.

The tubes described throughout this manual were designed principally for the use of the Mark 14 and Modifications torpedoes. Other types of torpedoes are also used in these tubes, and in some of these it is necessary to use a gyro setting socket adapter in the gyro setting socket in order to permit the setting spindle of the tube unit to engage the socket to

Figure 172 Adapter for gyro setting spindle socket, used when torpedoes other than the Mark 14 and Modifications are used in tubes described in this pamphlet.

set the gyro mechanism in the torpedo.

This is due to the fact that in earlier submarines the gyro setting mechanisms were on the outboard side of the tube, and the stroke of the gyro setting spindle (upon which there was no particular reason for imposing any limitation) was established as about 3.30 inches. For greater convenience of operation, the gyro setting mechanisms were later placed on the inboard side of the tube, and the restricted space between the port and the starboard tubes made it necessary to decrease projections inboard of the tubes. Hence the stroke of the gyro setting spindles was reduced to 2.20 inches.

The adapter (shown in Figure 172) is installed in the gyro setting socket of the torpedo by means of a square locking plate. The sides of this locking plate are in alignment with the sides of the square end of the adapter body when the adapter is inserted in the gyro setting socket of the torpedo, and are held in this position by the engagement of a key on the locking plate with a keyway on the end of the adapter body, the parts being held in engagement by the pressure of a spring under the head of the locking screw, to which the locking plate is rigidly secured.

After the adapter is completely inserted in the gyro setting socket, the engagement between the key

Upon the release of the pressure on the head of the locking screw, the spring pressure will cause the locking plate to become engaged with the adapter body in the new position, and the adapter will be securely held in the gyro setting socket by the engagement of the corners of the locking plate with the undercut in the bottom of the gyro setting socket.

In submarines of latest construction at the date of

(1) Certain gears are made of phenolic com pound.

(2) Parts of similar material are introduced in shaft couplings.

(3) Housings in which noise is apt to originate are mounted on material which does not readily transmit sound.

The materials so used are not as strong as metal, and are apt to wear quicker. They should, therefore, be given particular attention whenever they show signs of weakness or excessive wear.

A torpedo set for low speed, for instance, may travel at a rate of 32 knots, and its range will be approximately 9,000 yards. Set for high speed, the torpedo may make 47 knots, and its range will be about 4,500 yards.

The speed, low or high, is determined in accordance with other factors which pertain at the time of preparing to fire, the same as with the depth setting and the gyro angle. Hence the speed setting mechanism on the torpedo tube is so arranged that the speed can be set up to the time when the firing mechanism interlock lever (A of Figure 68) is thrown from "Muzzle Door Unlocked" to "Tube Ready to Fire," the same as the depth setting mechanism.

When loading a torpedo into the tube, the mechanism on the torpedo is set at low, if a two-speed torpedo, or to intermediate if three-speed. Likewise, the setting mechanism on the tube must be set at low.

Briefly stated, a speed setting mechanism consists of a spindle having a three-lobed head which is specially formed so that it will engage the socket in the torpedo only in one position, with a crank, shafting and gearing for turning the spindle, a handle with associated lever for engaging and withdrawing the spindle, and interlock details which engage the interlock sleeve so that the tube can not be fired with the spindle engaged, so that the spindle can not be engaged when the tube is ready to fire, and so that the spindle can not be turned except when all the way in nor retracted unless fully thrown to either of its two positions.

On starboard bow or port stern tubes, the socket in the torpedo is on the outboard side of the tube, the side farthest away from the center line of the vessel, hence the cross over type of speed setting

Figure 178 Showing lug (A) on collar of interlock sleeve releasing interlock bolt to permit movement of engaging and disengaging lever to spindle in position.

Figure 180 Showing pointer moved to high speed position as hand crank is moved up, interlock bolt still engaging lug on collar of interlock sleeve.

Figure 181 Showing interlock bolt moved to release lug on collar of interlock sleeve as engaging and disengaging lever is moved to spindle out position, torpedo having been set for low speed.

The simple type of speed setting mechanism is shown, detached from the tube, in Figure 175. Here the right hand is holding the lever for engaging and disengaging the spindle, the palm of the hand pressing the latch which locks or unlocks the lever so it can be moved from one position to the other. In this case the lever is in the spindle in or engaged position. The left hand is holding the crank for rotating the spindle to set the speed, the position shown being for low speed, as shown by the pointer on the indicator plate. Note that the index collar (E) in Figure 175, which will be described more fully later, is released from the lug on the base, unlocking the hand crank so it can be rotated.

Figure 176 shows the engaging and disengaging lever in spindle out position, and the speed setting hand crank in high speed position, as shown by the pointer on the indicator plate. Note, also, that the index collar is engaged by the lug, locking the hand crank in the high speed position so it can not be rotated while the spindle is disengaged from the socket in the torpedo.

The cross over type of speed setting mechanism, as already stated, operates on the same basic principle as the simple type, the difference being that the two shafts (the engaging shaft connected with the engaging and disengaging lever, and the worm and shaft connected with the speed setting handle) extend across the tube to an intermediate pedestal on the outboard side, this pedestal carrying the fork and gear which moves and rotates the operating shaft leading to the spindle housing, as shown in Figure 174. This is shown again in Figure 177, which also shows the location of the speed setting controls with relation to the depth setting mechanism.

The speed setting mechanism, like all the other operating mechanisms, is linked up with the tube interlocking system. Referring to Figure 177, (F) shows the lug on the collar of the interlock sleeve

Figure 182 Back view of speed setting mechanism (showing setting wheel now being replaced by hand crank). (A) Index collar and (B) Lug on base which engages index collar to lock speed setting wheel or hand crank; (C) Fork on engaging and disengaging lever which moves operating shaft horizontally to engage or disengage spindle; (D) Interlock bolt connected by lug on fork attached to engaging and disengaging lever; (E) End of interlock bolt engaging lug on interlock sleeve.

Figure 183 Back of speed setting mechanism, showing (A) Index collar engaged by lug on base; (B) Interlock bolt in spindle out position, releasing (C) Lug on interlock sleeve.

Figure 185

Figure 186

In Figure 178, the lug on the collar of the interlock sleeve has moved to release the interlock bolt so the engaging and disengaging lever can be moved to spindle in position, as shown in Figure 179. Here, in Figure 179, the indicator plate has been removed to show the pointer which moves back ward and forward to show low or high speed as the speed setting handle is rotated. Also, this shows the full view of the interlock bolt which is thrown by the rotation of the spindle engaging cross shaft in such a way that the interlock sleeve, when the firing interlock lever is in the "Muzzle Door Unlocked" position, can not be rotated until the spindle is retracted, and conversely, so that, when the spindle is out, it can not be re-engaged so long as the firing interlock lever is in the "Tube Ready to Fire" position.

Figure 180 shows the pointer moved over to high speed position as the speed setting hand crank is turned upward, the interlock bolt still engaging the lug on the interlock sleeve.

In Figure 181, the engaging and disengaging

Figure 187

A close up view of the interlock bolt from the rear of the housing is shown in Figure 182 (this showing the hand wheel which was originally fitted but is being replaced by the hand crank for rotating the spindle). Here the engaging and disengaging lever is in the spindle in position, the interlock bolt being moved over to engage the lug on the interlock sleeve.

Figure 183, the same view as Figure 182, shows the interlock bolt moved back as the lever is moved to disengage the spindle, the end of the bolt clearing the lug on the interlock sleeve. Both Figures 182 and 183 illustrate the simple speed setting mechanism.

Note that the interlocking system acts to lock the speed setting mechanism after the speed has been sot and the spindle removed or retracted from the socket in the torpedo. And conversely, the interlock halt on the speed setting mechanism locks the interlocking system and thereby prevents improper operation of other mechanisms while the speed setting spindle is engaged in the socket of the torpedo for setting the speed.

Still referring to the simple mechanism: As the interlock bolt acts to lock or release the engaging and disengaging lever, so also does the index collar on the operating shaft act to lock or release the speed setting hand crank. This index collar is shown in Figures 175 and 176, also in Figures 182 and 183. As shown in Figure 182, the operating shaft is moved horizontally, backward or forward, by the fork attached to the engaging and disengaging lever. When the spindle is disengaged from the socket in the torpedo, one of two slots in the index collar is engaged by a lug on the base of the housing, as shown in Figure 183. In Figure 182 the index collar is shown released from the lug so the operating shaft can be rotated to set the speed.

The speed setting hand crank can not be turned to rotate the operating shaft while the engaging and

In the cross over type of mechanism, the operation is essentially the same as in the simple type. The index collar has two slots, as shown in the close up view in Figure 184. Here one slot in the index collar is engaged by the lug after the mechanism has been set for high speed and the spindle has been retracted. Figure 185 shows the second slot in the index collar engaged by the lug after the mechanism has been set for low speed. The index collar unlocked, and in high speed position, is shown in Figure 186. Figure 187 shows the index collar unlocked and in low speed position, and Figure 188 shows the collar half way between the high and low speed positions.

When studying these views of the index collar it is well to recall that, as previously stated, the operating shaft is moved horizontally by the engaging and disengaging lever to engage or disengage the

Figure 189 shows the cross over type of speed setting mechanism detached from the barrel. The spindle is shown in the in or engaged position, the engaging and disengaging lever being in that position. The hand crank is shown in high speed position, the pointer being at high on the indicator plate.

Figure 191 shows the parts of the cross over attachment, disassembled at the left, and assembled at the right, while Figure 192 shows the parts which assemble into the intermediate pedestal. Tracing the operation of this part of the mechanism from the parts as shown in these illustrations, it will be

Figure 193 shows the operating shaft and connecting parts (disassembled) for the simple type of speed setting mechanism. Figure 194 shows the operating shaft, levers, and connecting parts as assembled in the housing, with the upper part of the housing removed to show the position of the different parts. Figure 195 shows the position of the operating shaft and the speed setting shaft as assembled in the housing. Figure 196 shows the housing and assembled parts from the back, indicating more clearly the action of the gear and fork on the operating shaft.

The end of the socket shaft also connects with a

The socket shaft (F in Figure 198) enters the spindle housing through a stuffing box, as shown at the left in Figure 197, the parts being shown at F, G, H, I, and J in Figure 198. This stuffing box, like all other stuffing boxes on the torpedo tube, should be kept tightened just enough to prevent leakage of water that enters the spindle housing. It should not, however, be tightened to the extent that it interferes with the movement of the socket shaft and prevents proper operation of the speed setting mechanism.