If you can see this text here you should update to a newer web browser

Normal | Highlight & Comment Highlighted Text will be in Yellow, but there are none yet

RESTRICTED   Ship: USS HOUSTON (CL 81) Cause of Damage: 2 Torpedoes Date: 14 and 16 October 1944 Place: Off Formosa Class: CLEVELAND (CL 55) Standard Displacement: 10,000 tons Length Overall: 610' 0" Extreme Beam: 66' 4" Draft Before Damage: 24' 1-1/2" Launched: 19 June 1943   1.     At 1841 on 14 October 1944, while HOUSTON was heeling to port during a high speed turn to starboard, an aircraft torpedo detonated in contact with the bottom at frame 75, midway between the centerline keel and the starboard bilge keel. The forward engine room, B-2, flooded immediately through a 10" diameter hole in the shell plating. Bottom structure was seriously damaged over an area 32' long by 24' athwartships (Photo 10, Plate 9). The keel was hogged 14" and cracked at frame 74 (Photo 11) Wrinkles extended around the girth to the bottom of the port side armor belt at frame 74. As HOUSTON was wracked by the seas, compression wrinkles developed amidships in the port main deck stringer plate and in some port main deck longitudinals. The forward fireroom, B-1-1, flooded in 10 minutes through a wrinkled and torn section of bulkhead 69, about 24 feet from the explosion. Boilers in this space were secured from valves on the third deck. The after fireroom, B-3-1, flooded very quickly through tears in the badly crumpled area at the bottom of bulkhead 79. Despite serious local damage, bulkhead 79 supported the bottom structure and limited distortion of the shell aft of that point (Photo 10). Propeller shaft #1 was broken, and drag on the propeller pulled the shaft 5 1/2' aft. This damaged the shaft glands in the stern tube and bulkhead 91, permitting the after engine room, B-4, to flood in about 30 minutes. No. 1 LP turbine was thrust upward against the overhead of B-2 and opened two scarfed joints in the 2" STS armored 3rd deck in the machine shop, B-307L. Spaces on the third deck flooded through these openings and damaged access trunks. The extensive flooding on the 2nd and 3rd decks is shown on Plate 9. HOUSTON underwent a period of negative initial stability while B-1-1 and B-4 were flooding. The vessel finally stabilized at a displacement of 20,900 tons with 6400 tons floodwater aboard, GM of +0.2", a 16° starboard list, and the main deck awash when the ship rolled. 2.     HOUSTON undertook, effectively, measures to establish flooding boundaries, unwater partially flooded compartments, reduce seepage, jettison topside weights and shore weakened     RESTRICTED - 19 -

RESTRICTED   structure. By 1200 16 October, displacement had been reduced to 190200 tons. The list had been reduced to 8° starboard, GM had increased to 4.5', and the main deck edge no longer dipped under as the ship rolled. 3.     At 1348 on 16 October, a second aircraft torpedo detonated at frame 145, starboard. The resulting hole in the bottom and side plating extended from frame 138 aft and partially across the stern (Plate 9, Photo 12). Compression failures occurred in main deck plating and longitudinala aft of frame 129 and in port and starboard shell plating aft of frame 115. Flexural vibration caused further distortion of previously damaged longitudinala in the midahip area under the main deck, port, and failure of some previously undamaged starboard main deck longitudinala. Main and 2nd deck plating was wrinkled to varying degrees throughout the ship. Flooding after the second hit increased displacement by 1100 tons to 20,300 tons, reduced the starboard list from 8° to 6°, and reduced GM to 4.0'. 4.     The longitudinal strength of ship girder was weakened seriously by these two explosions. About 926 square inches of structural material, including the damaged main deck stringers and longitudinals, were destroyed or rendered ineffective in the midship section where greatest longitudinal bending moment occurs. This represented a 24% reduction in the area of the intact midship section. Since most of the damage was near the bottom of the ship girder, the neutral axis of the section moved upward 3.6'. Section moduli to the main deck and keel were reduced respectively to 75% and 53% of the intact condition. 5.      HOUSTON continued damage control measures to:     (a)  Confine flooding, eliminate free surface, lower the center of gravity of the ship, and reduce list. When the ship arrived at Ulithi on 27 October, the starboard list had decreased to 2° and mean draft had decreased 5".     (b)  Reduce fire hazards.     (c)  Strengthen damaged structure. Bulkheads of the flooding boundary were shored. Stiffeners to reinforce some of the damaged main deck longitudinals were fabricated from 15# and 20# plate, carried for damage control purposes (Plates 10, 11, Photo 13). Webs of the replacement girders were cut to the contour of the damaged longitudinals.       - 20 - RESTRICTED

RESTRICTED           All girders were of sufficient length and had tapered end connections to provide continuity of structure. These were the most extensive repairs to longitudinal strength taken during World War II by a ship's, force underway. Analysis shows, however, that the repairs replaced only 38 square inches or 4% of the damaged area at frame 75. The neutral axis was raised 0.2'; the section modulus to main deck was increased by 3%, or to 78% of the intact condition; the section modulus to keel was increased l% to 54% with a corresponding decrease in tensile stress in the keel. 6.     At Ulithi there were no drydocking facilities capable of handling HOUSTON. Repair efforts were directed towards regaining buoyancy and restoring watertight integrity, increasing longitudinal and local strength, and rehabilitating machinery and electrical components. Divers were used to determine the extent of damage to the underwater body so that plans for repairs could proceed. When HOUSTON arrived at Ulithi the major spaces which still were flooded were the four engineering spaces, B-301E, B-306E, B-307L, B-311E, B-311L, and the 3rd deck and lst platform spaces aft of bulkhead 136. Measures undertaken were:         (a)  Regaining buoyancy and restoring watertight integrity.       (1)  A 6" salvage pump was used to unwater B-313L after divers had entered the compartment and closed door 3-79-3 and 3-85-1. Although most of the oil had been skimmed from this space before pumping, a small amount remained. This remaining oil greatly increased the labor required to clean the compartment. The ship's force used greater care in removing oil from other compartments and were convinced that this procedure saved much time and labor.       (2)  Divers examination indicated that a section of shell plating in way of No. 1 shaft stern tube was pulled away from the hull. Blankets and kapok life jackets stuffed into the stern tube through this opening sealed the leak sufficiently to permit pumping the after engine room. When the water level reached the uper level gratings,       RESTRICTED - 21 -

RESTRICTED             bulkhead 91 was inspected for evidence of incipient failure and the exposed part of the bulkhead was shored. When this was completed, the space was completely unwatered and shores were installed over the entire bulkhead. All leaks around pipe lines and cables in bulkhead 91 were plugged. Welded steel boxes were installed to seal leaks around No. 1 shaft in bulkhead 91 and the stern tube.       (3)  Holes in bulkhead 69 were patched temporarily from B-2 by divers. As water was pumped from the forward fire room, bulkhead 69 was inspected and shored from the forward side. Tears were then sealed with welded steel boxes.       (4)  Removal of water from B-1-1 and B-4 reduced the draft so that only 3' of water remained in B-306E and B-307L. B-307L was entered from the 2nd deck through trunk B-309T and door 3-70. Timbers were laid around the displaced portion of the armored deck, shored in place, and calked. Deck drains in B-306E were plugged and the two compartments were unwatered. Welded steel brackets were installed to secure the timbers around the raised plating. Then the shores were removed, all leakage was calked, and a watertight steel box was welded around the edge of the damage area enclosing the break and the wood patch.       (5) A 10# transverse bulkhead 6' high was built across the deck of the hangar at frame 138-1/2. When this bulkhead had been tacked in place by underwater welding, the hangar forward of this bulkhead was pumped and welding of the bulkhead was completed. Two 4' high bulkheads were installed to subdivide the forward part of the hangar (Photo 14). This restored buoyancy and reduced free surface in the stern area, reduced the likelihood of flooding C-416A and C-417A, and provided access to C-419A, C-421A, C-11V, C-12V and C-14V.       (6) C-419A and C-421A were filled with decomposed provisions. Divers entered through hatches 3-139-2 and 3-145. The provisions were floated up through the hatches and out through the torpedo hole at frame 145. Wooden cofferdams were built around hatches 3-139-2 and 3-145. The access opening at frame 139 in the starboard longitudinal bulkhead was sealed to permit           - 22 - RESTRICTED

RESTRICTED             pumping the port and center sections of C-419A. The access opening in the starboard longitudinal bulkhead at frame 146 was sealed to permit unwatering the port section of C-421A. When this was completed a new hatch leading to C-419A was installed in the unwatered section of the hangar. A hose connection was installed in bulkhead 144 to provide drainage facilities for the unwatered portion of C-421A. Hatches 3-139-2 and 3-145 were then blanked and the cofferdams removed.     (7)  In addition, liquid weights were temporarily removed from tanks in the midship area and the ship was listed to port to facilitate repairs to the 3rd deck.   (b) Improving longitudinal and local strength.             (1)  HECTOR (AR7), assisted by HOUSTON, undertook structural repairs to compensate insofar as possible for the loss in longitudinal strength. 24" T longitudinals were installed on the main, 2nd, and 3rd decks as shown on Plate 11. The 2nd and 3rd deck longitudinals, in conjunction with the stanchions, were intended to form a deep box girder bridging the damaged area to increase the rigidity of the hull and insure that the available strength members would develop their maximum strength. The 2nd and 3rd deck longitudinals, being near the neutral axis, were much less effective than were those on the main deck in increasing the moment of inertia of the section; in this instance a 2nd deck longitudinal was 44% and a 3rd deck longitudinal was 10% as effective as one on the main deck. These repairs added 252 square inches of material to the section and raised the neutral axis 11'. The section moduli to the main deck and keel were restored to 91% and 58% of their respective intact values.             (2)  In way of the after hit, badly damaged shell plating was cut away and temporary side plating, reinforced by longitudinal and transverse girders, was installed to tie together the remaining structure and to provide a partial breakwater against following seas (Photos 15, 16).     RESTRICTED - 23 -

RESTRICTED 7.     Calculations made for HOUSTON on a standard wave under the various conditions existing during this period show the reduction in tensile stress in the keel resulting from the measures undertaken to have been:         Stress reduction effected by structural repairs enroute Ulithi l% Stress reduction effected by structural repairs at Ulithi 4% Stress reduction effected by dewatering at Ulithi 16% 8.     After tow to Manus, HOUSTON was drydocked in ABSD 2 for temporary repairs to the underwater body. The COMSERON 10 local representative directed repairs which required 12,000 man days.         (a) Midship Area (Plates 11 and 12)               (1)  Shell plating, longitudinals, transverse frames, and inner bottom were cut away between frames 70 and 79 and from the keel to #8 longitudinal (Photos 17 and 18). At frame 79, the shell plating was about 11" inboard of the molded line. Longitudinals 1 to 5 and the associated inner bottom were cut away back to frame 81 and then restored to their original strength. Welded straps were fitted on both sides of the crack in the vertical keel at frame 74 1/2. 30" x 12" - 20#/30# welded T replacement longitudinals were installed between frames 70 and 79 (Photo 19). Deep transverse frames were replaced by intercostal 30" x 12" - 20#/30# welded T's. 30# shell plating was installed in two flat sections with a knuckle at longitudinal 5 (Photo 20).               (2)  Damaged centerline stanchions at frame 72 and 76 were replaced by 24" I sections with bracketed ends. Two additional 24" I stanchions were installed over the deep wrinkles in the shell plating frames 79-85, starboard (Photo 21). The cracked area in E strake at frame 75, starboard, was cut out and replaced by a 30# doubler. Smaller cracks were drilled at both ends, then welded and covered with a doubler.     - 24 - RESTRICTED

RESTRICTED             (3)  Plating and stiffeners in damaged portions of bulkheads 69 and 79 were replaced to restore original strength and watertightness.           (b) Repairs to After Torpedo Damage.               (1)  Damaged structure was cut away. 36" x 8" - 15#/15# T section transverse frames were installed at 4' spacing to conform to the original design. 12" T intercostal longitudinals were fitted. 15# flat plating was installed, with a knuckle at the connection of the bottom plating to the side plating. At the lst platform level, transverse I's were installed at each frame (Plate 13, Photo 22). At frame 145 a cracked portion of the keel was replaced. At frame 128 a crack in the keel was welded and strapped.           (C) Repairs to Rudder.               (1)  Drydock inspection showed that the after portion of the rudder was 20° out of line with the forward portion and that the top was badly distorted. Therefore, the rudder was cut just aft of the stock; the top portion was replaced, and the after portion was reinstalled in proper alignment (Photos 23 and 24).       RESTRICTED - 25 -

	Photo 10: USS HOUSTON (CL 81) Damage to bottom from first torpedo
	Photo 11: USS HOUSTON (CL 81) Crack in 30# vertical keel at frame 74 1/2. Keel raised 14" at this point.
	Photo 12: HOUSTON (CL 81) Looking outboard at damaged after section of hangar. Note tear in shell plating and opening between shell plating and main deck.
	Photo 13: HOUSTON (CL 81) Typical repairs made by ship's force to longitudinals under main deck.
	Photo 14: HOUSTON (CL 81) Temporary bulkheads in hangar.
	Photo 15: HOUSTON (CL 81) Repairs installed at Ulithi in way of after damage. Note shell plating and girders at main deck.
	Photo 16: HOUSTON (CL 81) Looking outboard at shell plating and supporting girders installed at frame 145 by HECTOR (AR7) at Ulithi.
	Photo 17: HOUSTON (CL 81) Looking aft and outboard showing hole cut in shell plating.
	Photo 18: HOUSTON (CL 81) Hole cut ready for installation of replacement structure. Note 24" I beam replacing damaged centerline stanchions.
	Photo 19: HOUSTON (CL 81) During installation of replacement girders. Note large radius corner of cut out area.
	Photo 20: HOUSTON (CL 81) Completed repairs to shell plating.
	Photo 21: HOUSTON (CL 81) Local stiffening at end of damage to shell plating frame 85 starboard.
	Photo 22: HOUSTON (CL 81) Structural repairs at stern.
	Photo 23: HOUSTON (CL 81) Damage to rudder and underwater body aft. Repairs to shell made at Ulithi.
	Photo 24: HOUSTON (CL 81) Completed repairs to rudder and shell in way of after hit.
	Plate 9: Torpedo Damage USS Houston CL 81
	Plate 10: USS Houston CL 81; Structural Repair to Main Deck by Ship's Force.
	Plate 11: Section at Frame 80 (Looking Fwd).
	Plate 12: USS Houston CL 81: Section "A A" showing method of connecting longitudinal replacement girders.
	Plate 13: USS Houston CL 81; Section FR. 144 Repairs to damage at stern.

The Below photos were not included with the original report but are provided for additional reference
	NARA Photo #: 19-N-106304 View looking aft from superstructure showing damage from the first torpedo hit, amidships, received off Formosa on 14 October 1944 while Houston was in a high-speed turn.
	NARA Photo #: 19-N-110859 View Looking aft from close to the same location as the above photo, showing damage to stern from the second torpedo hit received off Formosa, 16 October 1944.
	Navy Historical Center Photo #: NH 98342 Photograph of damaged stern, starboard side, taken while Houston was under tow to Ulithi in mid to late October.
	NARA Photo #: 19-N-110837 Damage visible through blown-off hangar hatch at the end of October 1944, after Houston had reached Ulithi Atoll.
	NARA Photo #: 19-N-105803 Photographed in ABSD 2 at Manus in November, 1944 after drydocking, showing amidships torpedo damage, starboard side. Note that the damage is centered inboard of the bilge keel; the massive damage in this area allowed most of the center of the ship to flood very quickly.
	NARA Photo #: 19-N-105833 Photographed in ABSD 2 at Manus in November, 1944 after drydocking, showing partial repairs to stern. This is a cleaner scan of the same picture that Photo 23 was reprinted from.

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

Houston Home | Repairs in Forward Areas Home | Ships Home | Researcher@Large Home