CONFIDENTIAL

 

TECHNICAL REPORT

_____________
Number

 

WAR DAMAGE REPORT --U.S.S. FRANKLIN (CV 13)

 

 

 

ACTION
OF
OCT.,30, 1944.
DATE

 

 

 

 

 

 

PUGET SOUND NAVY YARD
INDUSTRIAL DEPARTMENT
SCIENTIFIC & TEST GROUP
CODE 274

 

 

 

 


 

CONFIDENTIAL

WAR DAMAGE REPORT -- U.S.S. FRANKLIN (CV13)

Prepared by Puget Sound Navy Yard

 

TABLE OF CONTENTS

Section Page
 
I Introduction  2
 
II Structural, Description and Discussion of Damage  3
 
III Hull Fittings, Description and Discussion of Damage  5
 
IV Piping, Description and Discussion of Damage  6
 
V Ordnance, Description and Discussion of Damage  8
 
VI Radio and Radar, Description and Discussion of Damage  9
 
VII Electrical & Machinery, Description and Discussion of Damage 10
 
VIII Ventilation, Description and Discussion of Damage 14
 
IX Effect of Flooding from Fire Fighting Water on Stability 16

Appendix "A" U.S.S. FRANKLIN (CV13) Photographs, Puget Sound Nos. 3979-44 to 3988-44 Incl., 3991-44 to 3996-44 Incl. 4010-44 to 4016-44 Incl., 4018-44 to 4021-44 Incl., 4026-44 to 4051-44 Incl., 4054-44 to 4065-44 Incl.

Puget Sound Navy Yard Photographs--3989-44, 3997-44 to 4002-44 Incl., 4005-44 to 4009-44 incl, 4017-44, 4022-44 to 4025-44 Incl., 4052-44 to 4053-44 Incl., 4066-44, 4526-44 to 4528-44 Incl.

 
Appendix "B" Puget Sound Navy Yard Sketch of Structural Damage
 
Reference (a) U.S.S. FRANKLIN (CV13) - War Damage Report for the Action with Enemy Aircraft on 30 October 1944. CV13/Al6-3/L11-1(50-Jd) Serial 0046

 

 

 

 

 

 

 

 


 

WAR DAMAGE REPORT -- U.S.S. FRANKLIN (CV13)

Section I  Introduction

1.     The U.S.S. Franklin was steaming at 18 knots in an area about 100 miles East of Samar Island, P.I. on 30 October 1944. At 1426 the ship was attacked by Japanese planes. Shortly afterward the ship was struck on the Flight Deck by a plane and its bomb load. The plane hit at frame 127 about 20 feet starboard of centerline as nearly as can be determined, and penetratod the Flight Deck. It is not known whether one or two bombs were carried by the plane; however, the force of the explosion was estimatod to be equivalent to that produced by a 500 lb. G.P. bomb. It is believed that the bomb load exploded at the Gallery Deck level. The condition of the ship at the time of the attack and the measures taken to maintain military efficiency and seaworthiness are described in the ships report, reference (a). The damage due to the explosion and fire, as determined by the Yard from an inspection of the vessel and discussion with the ship's personnel, is described in this report.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 2 -


1.     The Japanese plane, carrying one or two instantaneously fuzed bombs, penetrated the Flight Deck to the Gallery Deck level and exploded, causing severe structural damage in the immediate vicinity and starting gasoline fires among the planes parked on the Hangar Deck.

2.     The Flight Deck plating was holed by the impact of the plane, and dished upward and buckled by the blast been frames 125 and 128, port, and frames 121 and 130 starboard. Structural bulkheads 125 and 128, although severely damaged, confined the explosion and reduced the fore and aft extant of the blast damage to the area between frames 121 and 131. Longitudinal Gallery Deck structural bulkheads between frame 121 and 131 were demolished or buckled (see Appendix "B"). The blast ruptured the starboard Hangar side plating at frame 127 just below the Flight Deck. The Gallery Deck plating in way of the explosion was demolished and buckled between frames 121 to 142 (Port) from the intense heat generated by gasoline fires on tha Hangar Deck. Transverse Flight Deck supporting girders at frames 113, 117 and 121 were warped slightly by the fire. (See Photos #3980-44 to 3995-44 incl., 4003-44 to 4007-44 incl., 4012-44 and 4016-44.)

3.     Although blast damage to the adjacent Flight Deck Plating and Gallery Deck bulkheads was severe, the effect on the principal foundation bulkheads supporting 5"/38 mounts nos. 5 and 7 was slight. An examination by this Yard disclosed no misalignment or binding in the mount, that might have directly resu1ted frou distortion of the foundation. (See photos #3981-44, 3983-44s 3984-44s, 4012-44 and 4016-44.)

4.     There was no evidence of damage to the Hangar Deck plating and beams; there were only a few isolated fragment holes in bulkheads in the Hangar space. The bomb elevator trunk was demo1ished from the Flight Deck to Forecastle Deck and severely buckled and distorted from the Forecastle Deck to the Hangar Deck. (See photos #4012-44 and 4016-44.)

5.     Blast from the explosion on the Gallery Deck traveled down the bomb elevator trunk to the 4th Deck, causing the trunk bulkheads to be dished out about 5 inches maximum midway between decks. The only apparent sign of rupture in these bu1kheads was a crack or weld failure at the corners of the trunk in way of the horizontal stiffeners and extending about 3 inches above and below the web of the stiffener. (See photos #4017-44, 4028-44, and 4061-44) Blast escaping through the bomb elevator door on the 3rd Deck damaged a short section of bulkhead 131 and a door in the bulkhead. (See photos #4029-44 and 4054-44.)

6.     The ship reported that after the bomb exploded on the Gallery Deck two separate explosions on the 3rd Deck occured, one in compartment B-319L and the other in compartment B-324L. Investigation of the resulting damage by the Yard also revealed the possibility of an explosion centering in compartment B-313E, undetected by the ship and, therefore, not mentioned in the ship's reports. The explosions presumably originated from the ignition of gasoline

 

 

- 3 -


 

vapors accumulated in these spaoes.

7.     The explosion in compartment B-313E dished the 2nd and 3rd Decks, with a maximum deflection on each deck approximately 2 1/2 inches at frame 115 port. The 2nd and 3rd deck transverses and longitudinal beams sustained a permanent deflection but no pronounced distortion or buckling. (See photos #4045-44, 4052-44, 4052-44, 4063-44, and 4064-44.) The explosion caused a slight buckling of stiffeners on bulkhead 111 (see photos #4022-44, 4041-44, and 4047-44) and dished the inboard longitudinal uptake enclosure bulkheads, frame 111 to 121, and tranverse uptake enclosure bulkhead 114 . (See photos 4033-44, 4035-44, 4036-44, 4044-44, 4046-44, 4048-44, and 4051-44.) It is interesting to note the nature of the tension failure of the connection at the top of the centerline stanchion on frame 117, since this structureal member is usually designed to withstand a compression loading. (See photos 4024-44 and 4042-44.)

8.     The explosion in compartment B-319L dished tho 2nd and 3rd Decks, producing a maximum deflection of about 12 inches in both decks. Transverse 113 and 117 under the 2nd Deck were wrinkled and distorted, showing definite failure due to excessive shearing and bending stresses in the girder. It should be noted that the shearing failure of the welded connection of the girder bracket to the face plate of web 113 under the 2nd Deck indicates either poor welding or insufficient weld metal to develop the full strength of the bracket. It is significant that the only rupture of the deck plating occurred in way of this shear failure of the beam end. (See photos #4030-44, 4031-44, 4037-44, 4038-44, and 4050-44.) Structural failures in the 3rd Deck transverse girders were very similar to those in the 2nd deck transverses. There were vertical shear failures at girder ends and also diagonal wrinkles in the web at the end of each girder, indicating a failure and deflection due to diagonal shear. (See photos #4025-44, 4026-44, 4049-44, 4056-44, 4058-44, and 4065-44.) The inboard longitudinal and transverse bulkheads, bounding compartments B-319L, suffered only slight damage from the explosion. The expanding gases blew off the watertight door on bulkheads 111 and 121, and escaped into compartments B-311L and B-323L.

9.      The explosion in compartment B-324L caused no appreciable structural damage; however, some lockers were smashed and tables thrown about.

10.     Fires in compartments below the Hangar Deck caused very little if any structural damage. Open hatches on the Hangar Deck that could not be closed due to the fire in the Hangar Space, permitted water and gasoline to flood the lower decks.

11.     In general, the structural damage had a minor effect on the ship's strength.

 

 

 

 

 

- 4 -


1.     As a result of the attack, two important items under the classification of hull fittings were damaged. The midship plane elevator was bulged upward by the bomb explosion (see photos nos. 3988-44, 3998-44, 3999-44, 4001-44 and 4002-44), and the bomb elevator trunk severely distorted by explosion of gasoline vapor, which was admitted to the bomb elevator through open doors on the Hangar Deck.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 5 -


1.     Damage to piping systems was not extensive; however, a brief description of the systems affected and pertinent comments follows.

2.     In the immediate vicinity of the hit, compressed sir system, steam heating system, fresh water system, aviation lub. oil system, and plumbing drains were damaged by explosion and fire. The ruptured portions of these systems were readily isolated by cut-out valves.

3.     A gasoline station on the Flight Deck was damaged by fire, and a gasoline hose burned on the Hangar Deck. No evidence of explosion was observed around the gasoline stations or piping. No design changes are recommended that offered in the "P.S.N.Y. War Damage Report on CVE27" in which it was suggested that the gasoline hose be stored inside the fume tight box with the filters and the defueling pump.

4.     (a) Damage to a firemain riser caused the loss of use of six fireplugs, sprinkling for compartments B-0219M and B-0315M, and one foam generator. The presence of dense smoke and fire on the damage control deck prevented use of cut out valves through which three additional fire plugs could have been returned to service. The part of the system affected by this damage was designed to permit isolation of the damaged portions, and is considered satisfactory as installed.
       (b) The segregation of the firemain as recommended in paragraph 16 of reference (a) was accomplished at Puget Sound Navy Yard during the recent overahaul. A similar provision for segregation of the firemain is shown on Bu. Ships Plan No. CV9-S4803-195760 "Firemain and Sprinkling System - Diamagrammatic Arrangement - Ultimate."

5.     Refernce (a) states that about 2000 tons of water from Hangar sprinklers and hoses collected on the Hangar Deck and decks below. A large part of the water came from the Hangar sprinkling system. The sprinkling and water curtain system cools the area in which it operates but does not extinguish gasoline fires. The FRANKLIN had standard commercial heads for sprinklers and S-1 and S-2 type sprinkler heads for water curtains. It is understood that for cooling, water in the form of fog is most effective. With this in mind, the Yard suggests that a more efficient Hangar Deck sprinkler system may be obtained by the use of L-11 fog heads in lieu of the comercial sprinkling heads, and high velocity fog heads properly spaced and directed downward in lieu of the S-1 and S-2 heads now installed in the water curtains. It is believed that equal or greater cooling may be obtained in this manner with a substantially reduced quantity of water. This would relieve the firemain system of excessive load and alleviate, to some extent, the problem of disposal of the large quantities of water now released in the Hangar Deck space by the sprinkling system (see section IX). It is believed that the high velocity fog heads would form an effective water curtain. If the L-11 heads are not considered suitable for mounting 18 feet above the deck, it is believed that fog heads could be developed for this service.

6.     The hydraulic valve control system showed exceptional resistance to damage. None of the installations was put out of order, although the panel in B-331E just

 

 

- 6 -


outboard ot the general workshop, frames 111 to 114, port, was tipped outboard about 30° by one of the explosions.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 7 -


1.     Damage to ordinance was slight. Sights on the 5"/38 Cal. Twin Gun Mounts Nos. 5 and 7 were overheated by fire and required a general cleanup and overhaul.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 8 -


1.     Radar equipment on the Gallery Deck between frames 79 to 96 suffered damage due to fire, and to salt water from fire fighting activities. A number of units were also put out of comission by shock from the bomb explosion.

2.     The SM spare console, OZ tube tester and two LW frequency meters on the Gallery Deck were damaged by fire and salt water. The BO and HM radars on the Gallery Deck, between frames 79 and 90, and the BL Radar in the Search Radar Room Gallery Deck between frames 93 and 96 were damaged by shock. Coaxial transmission lines for BL Radar and SK Radar were puntured by shrapnel near the SK Antennae platform.

3.     A number of radio remote control cables between Radio I and III, and Radio II and III on the Gallery Deck frames 95 to 150 (stbd.) were severed and burned. Cables at frame 60 Gallery Deck about 30 feet off centerline were broken, and two gas filled coaxial transmission lines were severed in the immediate vicitinity of the bomb hit.

4.     No unusual or serious condltions involving Radar or Radio equipment developed as a result of the explosion and fire. It is considered that the effect on this equipment was minor compared to total ship damage.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 9 -


WAR DAMAGE REPORT -- U.S.S. FRANKLIN (CV13)

Section VII Electrical and Machinery

1.     The major portion of damage to electrical equipment was due to fire, secondary explosions from gasoline vapor, and salt water from fire-fighting activities, rather than the direct result of the bomb explosion. The following discussion includes non-vital equipment and cables to indicate the overall extent of damage more clearly. Although certain of this damaged equipment is not vital to the military efficiency of the vessel, it does affect the comfort and morale of personnel.

2.     Detail of the damage to to power driven auxiliaries, distribution circuits, and appurtenances are briefly described below:

   (a)   Airplane Elevator No. 3 - Traveling cables and control wiring to limit switches damaged by exlposion and fire. Stanchion motors and controllers 6, 7, and 8 and power supply cables damaged by fire and salt water. Motor and controller 6 were not repairable.
   (b)   Upper Stage Bomb Elevator No. 3 - Controller demolished (see Photos Nos. 4060-44 and 4062-44) by gasoline vapor explosion on 3rd Deck. Control cables to limit switches and push buttons and power supply cables burned. Although the motor was in the blast vicinity it was only affected by salt water. Motor could be repaired.
   (c)   Torpedo Elevator frame 135 (Stbd.) - Power supply cables destroyed by fire.
   (d)   Hangar Sprinkling Control - All motor driven valves for sprinklers and water curtains in bays 3, 4 and 5 opened satisfactorily from remote control. However, subsequent fire damage to control cables prevented the closing of valves by remote control from any station. Water later entered ruptured controller cabinets, damaging controllers. Hand operation of valves was necessary after the fire.
Note: this system has not been modified as authorised by Ship Alt. CV510A.
   (e)   Ventilation system - Discussion with ship's officers revealed that at first indication of fire, the hangar conflagration station reported to the main distribution switchboards, at which time the major portion of ventilation power feeders were disconnected. Power was restored as conditions permitted and vent sets capable of further operation restarted. The non-watertight ventilation service load center panel number 2-93-2 and power panel number 2-93-4 were grounded and short circuited, probably due to condensation of steam from adjacent damaged areas. As a consequence, about twenty-eight sets which provided ventilation to spaces between 60 and 100 from the hold through the Island Structure (exclusive of the machinery spaces) were inoperative during this period. The panels were dried, and restored to service after approximately eighteen hours. The duct work around axial fan number 3-103-02 for number one engine room exhaust was submerged in salt water. As a result, water entered the motor through the cable terminal box which, on the day following action, caused a short circuit of sufficient intensity to trip the

 

 

- 10 -


         distribution panel AQB type circuit breaker. The motor was dried and restored to service by ship's force. Number one engine room axial type fan number 3-103-1 was similarly submerged. Although water was later found in the terminal box, the operation of the fan was not interrupted. The terminal boxes for the later two vent sets have elliptical shaped, gasketed covers with major and minor diameters of approximately nine inches and six inches, respectively, which are secured by only two machine screws at opposite ends of the shorter diameter. While this method of securing may meet standard water proof requirements, it is believed that more securing screws should be used to prevent leakage in the event of submergence. Vent fans and controllers numbers 3-101 and 3-102, located in blower room B-308-E, were submerged for about three days. The motors and controllers were reconditioned by repair forces afloat and reinstalled. Although the controllers were severly damaged by salt water and sufficient spare parts for complete repair were not available, they were repaired so that single speed operation of the two-speed motors was possible.
 
   (f)   Several non-vital power distribution panels and two load, center panels sustained damage. Since certain of these panels were in the area of fire, feeder and main cables were likewise damaged.
1.   Panel 02-117-1 and cables were destroyed. This panel supplies the optical workshop equipment which was also destroyed.
2.   Panel 02-117-2 and cables were destroyed. This panel supplies the entire airplane electric service system forward of frame 132. The three 25 KVA transformers located adjacent to the power panel which supply power to the circuit were also damaged by fire.
3.   Panel 02-124-1, connecting feeder and main cables, and the three 7.5KVA transformers supplying power to the circuit were destroyed by fire. This panel furnishes power to the instrument flight room equipment which was also destroyed.
4.   Load center panel 3-411-4 from which power is distributed to the electric workshop, laundry, aviation instrument shop, pipe and copper shop, print shop, and cobbler shop was damaged by salt water. This panel was restored to service by replacement of damaged circuit breakers.
5.   Load center Panel 3-126-2 was damaged from the explosion on the 3rd Deck. Although it is a watertight panel the door was bulged outward by the explosion, permitting entry of salt water. Circuit breakers in the panel which were damaged by the water were replaced by ship's force and power was restored. Power for the crew's galley equipment is obtained from this panel.
6.   Power panel 3-121-4, a watertight panel supplying galley equipment was not damaged except that the door was likewise bulged outward, thus destroying watertightness.
 
  (g)   Degaussing Coils - Coils FI-QI and PP-QP were destroyed by fragments and fire, or damaged by salt water between frames 104 and 145 Gallery Deck (Port).
 
  (h)   Machine Shop Equipment - Motors and controllers mounted within approximately three feet of the deck were submerged. Machine shop power distribution pane1 3-111-2 and all main cables supplying shop equipment were subjected to salt water and became unserviceable.

 

- 11 -


  (i)  
Crew's Galley - The secondary explosion on the 3rd Deck forced the tops of the four roasting ovens downward onto the wire round, ceramic-supported heating elements breaking the supports and short-circuiting the top section elements. The ship reported that sufficent equipment was restored for crew's mess within about three hours after securing general quarters.
 
  (j)  
Laundry - Flooding of the laundry with salt water caused motors and controllers for extractors 1, 2, and 3, and motors for the dryers and mangle to become inoperative.
 
  (k)  
Shore Connection Box - Box located an 2nd Deck frame 111 damaged by- fire.
 
  (l)  
Air Conditivning Unit - Motor and controller for Unit No. 5 located on Gallery Deck frame 131 (Port) were damaged by fire and saIt water. Repair of this equipment at the Yard was found practicable.
 
  (m)  
Print Shop - All electrical motors damaged by salt water.
 
  (m)  
Casualty Power Generator - The exciter of the 6OKW casualty power diesel generator number two located on thw Hangar Deck at frame 101 was a sprayed wth salt water which would have caused this machine to be unavailable for services had it been required.

3.      Damage to lighting circuits by explosion, fire, and salt water caused loss of lighting on the Gallery Deck between frame 112 to 169, Hangar Space frames 81 to 169, and Forcastle Deck between frames 107 to 149 (Stbd.). Lighting on the second deck between frames 79 to 121 was lost, it is presumed, due to short circuit to in associated networks which casued the three 15KVA transformers at frame 130 to become overheated thus damaging windings. Tempoary 115 Volt supply was obtained by using casualty power connections to the 115 Volt bus on No. 3 main switchboard, directly to lighting distribution panel 2-130-1. Lighting circuits from the 15KVA transformer tank at frame 111 (Stbd.) were temporarily interrupted when the circuit breaker on No. 2 main switchboard was tripped, presumably by overloads from short circuits in the lighting network. The breaker was closed after damaged circuits were isolated. The transformers, although subjected to salt water, were tested, and found satisfactory. 3rd Deck lighting between frames 123 and 131 was also lost through submergence of three 15KVA transformers at frame 110 and resulting grounds and short circuiting. Lighting was temporarily restored by using casualty power connections from the 115 Volt bus on the No. 2 main switchboard to lighting distribution panel 3-107-1.

4.      Within five hours after the attack sufficient lighting for immediate needs was restored. However, cables which had absorbed water subsequently became grounded, neccesitating additional temporary remedial circuits.

5.      Damage to the Interior Communication system was confined to circuits within the severely, damaged areas and did not adversely affect any circuits vital to the operation of the ship. JA sound powered telephone circuits on the Gallery Deck between frames 100 and 150 were lost through explosion and fire. This portion of the circuit was isolated at the main battery telephone switchboard. Other systems affected in the damaged area included 1, 3, and 19MC announcing, ship's service telephone, and telephone call bells. Faults in these circuits were quickly isolated. The character receiver projector units and associated wiring in squadron

 

 

 

 

 

- 12 -


ready rooms numbers 3, 4 and 5 were destroyed.

6.     Damage to the Fire Control system consisted of the loss of 115 Volts, A.C. supply to the Mk 14 lead at sights of 20mm guns number 23, 25 and 27 through 47, inclusive. This was due to the destruction of the lighting circuits on the Gallery Deck which supply power to these units. The multiple conductor cable containing the elevation, train and gun firung circuits between 5"/38 mount number 7 and the Mk. 51 director was severed by the explosion of the bomb. However, the equivilent circuits to the mount from the plotting room remained intact.

7.     The investigation of damage to electrical equipment produced several interesting facts as to the reliability of the equipment. Numerous motors, transformers, fittings, etc., subjected to salt water, although temporarily eliminated from service, were put back into operation after a simple drying process. Many cables, which were burned so that large quantities of outer insulation oozed through the armor braid, continued to carry current and retained a reasonable insulation resistance. Photos Nos. 3995-44, 4027-44, 4032-44, 4033-44, and 4037-44 clearly indicate that electrical equipment, boxes, fittings, cable racks, etc., withstood shock from explosion which was so violent that adjacent and supporting structure were badly distorted. In contrast, however, water was reported in some water-tight connection boxes, presumably due to improperly secured covers.

8.     Deficiencies and General Comments.
       A considerable number of casualties occurred to non-watertight electrical circuits, due to entrance of water during fire fighting activities. Although the circuits were non-vital, they presented a fire hazard from short circuits, and the possibility of adversely affecting the main generating plant. It seems that a greater degree of reliability could be obtained if the major portion of the outlying wiring network, including equipment and fittings, were of the watertight type. However, one disadvantage was noticed; the cover of a sheet steel connection box, and doors on certain watertight panels were bulged outwards through a reduction of pressure in the area from nearby exlosions, while adjacent non-watertight panels were not affected. It may be possible to strengthen the covers of watertight equipment, with only a slight increase in weight, to withstand these pressures better. Certain casualty power terminals were likewise grounded through entrance of water. This shows the need for all casualty power terminals in the outlying deck areas to be protected by watertight covers.
       The three 60KW dripproof casualty power diesel generators located on the Hangar Deck at frames 65, 101 and 180 may become splashed with salt water when accumulation of hangar sprinkling water on the deck due to list or roll of ship. The lack of suitable protection from the hangar sprinkling system for these units is undesirable.

 

 

 

 

 

- 13 -


1.     Damage to ventilation from the hits, fire and salt water, although extensive, was not serious. The damage may be briefly described as follows:

Ventilation systems were demolished in the Gallery Deck area from the concussion of the bomb explosion.
Considerable damage to ventilation ducts, fans, air conditioning equipment and insulation resulted from the intensive fires.
Flooding caused some damage toventilation equipment. This is discussed in paragraph 2 (a) and 2(d).
Several ducts were bent where they passed through bulkheads and structural members which shifted as a result of explosions.
  (a)  
Large Flat sided ducts and watertight valve housings were crushed and broken in the areas of heavy explosions.
 
  (b)  
 
  (c)  
 
  (d)  
 
  (e)  

2.     Certain systems and equipment suffered damage which may be minimized or prevented through minor design changes. A discussion of the damage and the recommended changes are given below:

Several ventilation valves in the 3rd Deck area along the longitudinal bulkheads, 30 feet to port in the Crew's Galley (8-318L) and the Crew's Messing Space (8-324L) were damaged while open and could not be closed. The watertightness of the longitudinal bulkhead was destroyed; however, no flooding took place through these open valves. If the valve housing was stiffened with a flange or flat bar, minor blast effects would not warp the housing and restrict the operation of the valve.
The large duct at 32 feet to port on the 3rd Deck between frames 101 and 102 was broken open, and water entered the Blower Room (B-308E) through the broken duct, and vent set 3-101 from the passage (B-310L). The water in the Blower Room shorted the two vent set motors, systems 3-101 and 3-102 in that space. If the Port list had been much greater this flooding might have extended into the wind tunnel on the 2nd Deck and from there to numerous other important spaces, throughout the ship. The great amount of fire and smoke which followed the hits might easily have entered the wind tunnel through damaged ventilation
  (a)  
The air intake trunks for boilers 7 and 8 were damaged above the Hangar Deck level, so that water from fire fighting entered Boiler Room No. 4 via the trunks and uptake space B-431-E and via the damaged bomb elevator. Heavy coamings could be installed at the Hangar Deck level to form the sides of the intake trunks up to about 12 inches above the deck. These coamings should be constructed to withstand considerable damage so that, even when the trunks are badly damaged, the coamings will remain intact, and water which accumulates on tbe Hangar Deck from the sprinkling system will not drain into the trunks.
 
  (b)  
 
  (c)  

 

- 14 -


Water entered the motors of the forward engine room exhaust vent sets,3-103-1 and 3-103-2, through the electrical connection boxes on the sides of the vent sets (see section, VII Paragraph 2(e)).
A small amount of water entered No.1 Machinery Room through ventilation supply system 5-109-1. The system was inspected and no damage was apparent; however, water could have entered the system at the intake opening as a result of near miss, and it might have entered the intake trunk at the 3rd Deck level (which was flooded) through the bolted plate gasket in the side of the trunk or through fissures caused by imperfect welding of insulation brackets to the side of the trunk. The trunk should be made watertight.
ducts. It is recommended that the shipalt pertaining to sectionalizing the wind tunnel on this class of carriers be accomplished as soon as praticable.
 
  (d)  
 
  (e)  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 15 -


WAR DAMAGE REPORT -- U.S.S. FRANKLIN (CV13)

Section IX Effect of Flooding from Fire Fighting Water on Stability

1.     Acording to reference (a), the displacement at the time of attack was 35,525 tons, and the corresponding GM was assumed to be 9.3 feet, based on the inclining experiment of 19 December 1942. (More recent inclining experiments of this class show that the GM is probably somewhat less.) The ship also reported, via memo from damage control to the first lieutenant, that the following voids were flooded to heights indicated to correct for list:

A-32V - - - 19 Ft. A-56V - - - 31 Ft.
A-38V - - - 22 Ft. A-64V - - - 33 Ft.
A-40V - - - 25.5 Ft. B-96V - - 28 Ft.
A-46V - - - 24 Ft. C-2V - - - 24 Ft.
A-48V - - - 28 Ft. C-10V - - - 21 Ft.
A-54V - - - 27 Ft.

Flooding of A-32V, A-38V, A-46V, A-48V,and C-10V was not reported in reference (a) apparently because the flooding effect diagram did not show any correction to list for these tanks. It was further stated in reference (a) that the ship listed 3 starboard, as a result of flooding from ship's sprinkling system, and then returned to 2 port after counterflooding had been stopped.

2.     Based on this, the maximum probable loss of stability has been computed to compare with the observed behavior of the vessel.

Estimate of GM (assuming full free surface and added weight of water)
GM prior to damage = 9.3 Ft.
Total loss of GM due to F.S.and added weight = 6.0 Ft.
GM after damage = 3.3 Ft.
The GM calculated from the moment of flooded voids, in correcting list from 3 starboard to 2 port, is 3.2 feet. Thus a close check on GM after damage is obtained. Hoowever, the list angles were estimates only and not accurate measured values. It should also be noted that the calculated loss of GM, due to free surface, is approximately three times as great as that reported by the ship. Since the amount of water on the various decks was changing during fire fighting, the effect of free surface may be considered as having varied from the maximum calculated by the Yard to a much smaller figure.
  (a)  
Large Flat sided ducts and watertight valve housings were crushed and broken in the areas of heavy explosions.
 
  (a)  
 
  (b)  

3.     In order to make the Flooding Effect Diagram more effective in estimating correction for list for this class of vessel, it is recommended that the angles be recorded to the nearest rather than the nearest . This will aid the ship's personnel in correcting list and prevent unnecessary counterflooding or transfer of liquids.

4.     Disposal of large amounts of water from Hangar sprinkling and firefighting activities which accumulate on the Hangar Decks and decks below, has been a serious problem on vessels of this class. To remedy this condition, some steps

 

- 16 -


have been taken, such as the installation of coamings around certain Hangar Deck hatches and heeling the ship to allow water to run over the side more readily. Puget Sound Navy Yard has installed, at the ship's request, two 8-inch drains in each elevator pit on CV14. While this is not considered entirely satisfactory, it will provide much greater facilities than the existing two 3-inch drains. A number of other ideas have been discussed and the following recommendations are made:

  (a)  
Cut dowm sheer strake coaming flush with Main Deck at frames 44 to 46 port, 173 to 176 Port and 198 to 201 Starboard. This was recommended to the Bureau in P.S. Speedletter CV9Class/S11(274) of 7 March 1945.
 
  (b)  
Install heavy coamings at each deck level in way of vent trunks and uptakes, so that blast damage to trunks at the decks will be minimized and prevent water on decks from entering trunk openings.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 17 -


 

 

 

     The following personnel of the Design Section assembled the data and prepared the Damage Report.

 

 

 

    Name
  Section
 
J. L. Chernoff
Electrical
 
C.W. Couch
Ventilation
 
I.E. Thorson
Hull Fittings
 
M. L. Scott
Flooding & Stability
 
S.J. Rowland
Structural
 
W.W. McIntosh
Piping
 
J.L. Eitel
Ordinance
 
A.R. Stover
Machinery
 
G. N. Allison
Photographer,
 
R.F. Wright
Radio and Sonar
 
L. E. Mabry
Radar and CIC
 
 
    Report edited and reviewed by - R.B. Couch & R.R. Stone

 

 

 

 

 

 

 

 

- 18 -


SOURCE: National Archives & Records Administration, Seattle Branch
Record Group 181, Ship Files ca 1940-1950 514962-73 (62A-140) Box 24
Declassification Review Project NND 958357

Transcribed by Tracy White, who is in awe of the sailors of this ship.

Transcribed by RESEARCHER @ LARGE. Formatting & Comments Copyright R@L.

CV-13 Franklin Kamikaze Attack Home | Ships Home | Researcher@Large Home