Evidence
11 evidence entries recorded; each entry has a stable permalink (#ev-1 … #ev-11).
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[1]NavSource Online: Submarine Chaser Photo Archive, SC-633 (ex-PC-633) - construction, designation timeline, specifications, disposal, commanding officer (verified live 2026-10-03) [other_primary]
- Locator
- NavSource 12/150633.htm header block, specifications block, Commanding Officers table
- Finding type
- vessel_history
- Finding
- NavSource timeline for this hull: laid down 20 March 1942 by the Mathis Yacht Building Co., Camden, NJ; launched 3 July 1942; commissioned USS PC-633, 9 September 1942; reclassified SC-633 in April 1943; destroyed 4 April 1946; struck from the Naval Register 8 May 1946. Call sign Nan - William - Oboe - George. Specifications: displacement 148 t.; length 110'10"; beam 17'; draft 6'6"; speed 21 kts.; complement 28; armament one 40mm gun mount, two .50 cal. machine guns, two depth charge projector 'Y Gun,' and two depth charge tracks; propulsion two 1,540bhp General Motors (Electro-Motive Div.) 16-184A diesel engines, two shafts. Commanding officer listed: LTJG C. J. Savaresa, Jr., USNR (1945). Page states: 'There is no DANFS history available for SC-633.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 1942-1946
- Population
- Mathis/Trumpy construction trades (1942); crew (1942-46)
- Limitations
- NavSource is a volunteer secondary compilation tracking NVR/DANFS data, not a primary registry - but it is the fullest hull-specific record located and its milestones are corroborated by uboat.net and shipbuildinghistory. 'Destroyed 4 April 1946' is given without location or circumstances. No asbestos or material content. No image of SC-633 is available on the page.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-01
-
[2]NavSource Online: Submarine Chaser Photo Index - PC/SC designation history and PC-461-class numbering blocks (verified live 2026-10-03) [other_primary]
- Locator
- NavSource 12/01idx.htm '110' Wooden Hull' and '173' Steel Hull' narratives; 497-class index line 'SC-633 ex-PC-633'
- Finding type
- historical_record
- Finding
- CORRECTION/context on the 'PC-633' designation: the NavSource index narrative documents that WWII expansion built two subchaser types - 110-foot wooden craft and 173-foot steel craft - and that 'by 1943, it was felt desirable to differentiate between the two types. The type symbol PC was retained for the steel 173-footers, and the separate symbol SC was adopted for the 110-foot vessels.' SC-633 is indexed 'ex-PC-633': this wooden hull was commissioned under the PC designation in September 1942 and reclassified to the SC series in April 1943. The index further documents the steel PC-461-class numbering blocks - PC-461 to PC-496, PC-542 to PC-627, PC-776 to PC-826, PC-1077 to PC-1265 - which do NOT include 633: no PC-461-class vessel ever bore the designation PC-633; the designation belonged to this wooden hull alone. The prior framing 'PC-633 never existed as a PC vessel' is correct for the steel PC-461 class but should not be read as saying the designation PC-633 was never used - it was this hull's commissioned designation for seven months.
- Verification
- verified
- Role
- correction
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 1942-1943 (designation window)
- Limitations
- Clarifies a designation nuance, not a material claim. The April 1943 reclassification month comes from the hull page (ev-01); the index narrative confirms the PC->SC differentiation program and that hulls carried numbers from one general series, explaining the gaps in SC/PC numbering. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-02
-
[3]uboat.net Allied Warships, USS SC-633 build table; Shipbuilding History / Naval Marine Archive Mathis Yacht Building (Trumpy) hull table - yard no. 260; uswarships.jounin.jp SC-497 compilation (Japanese secondary compilation rendering the disposal as 'destruction/disposal' (hakai shobun) 1946/4/4) [other_primary]
- Locator
- uboat.net ship/8850 build table; navalmarinearchive.com/sbh/shipyards/yachtsmall/trumpynj.html hull table rows 249-269 (Gloucester City section, hull 260 = SC 633)
- Finding type
- vessel_history
- Finding
- Corroborating build data: uboat.net records SC-633 ordered 30 July 1941, built by Mathis Yacht Building Co. (Camden, NJ), laid down 20 March 1942, launched 3 July 1942, commissioned 9 September 1942 (no history data beyond the build table). The Shipbuilding History Mathis/Trumpy yard table lists hull 260 = SC-633, US Navy subchaser, 148d/110ft, delivered 9 September 1942, 'destroyed 1946' - and places the wartime Mathis SC production (hulls 249 onward, including 260) under its 'Built in Gloucester City by John Trumpy & Sons' section, reflecting the yard's mid-war relocation from Cooper Point, Camden to Gloucester City and its 1943 renaming to John Trumpy & Sons. A third compilation (uswarships.jounin.jp) lists SC-633 under Mathis Yacht Building Co., commissioned 1942/9/9, reclassified to SC-633 (wooden-hull submarine chaser) 1943/4, and 'hakai shobun' - destruction/disposal - on 1946/4/4, supporting the reading of 'destroyed' as a deliberate disposal act rather than a combat/weather loss.
- Verification
- partial
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 1941-1946
- Population
- Mathis/Trumpy construction trades (1941-42)
- Limitations
- Secondary compilations: uboat.net supplies the 30 July 1941 order date found nowhere else (unverified against contract records); the builder-attribution conflict (Camden/Mathis per NavSource vs Gloucester City/Trumpy per the Colton table's sectioning) is unresolved - the operating company was the same Mathis Yacht Building Co. becoming John Trumpy & Sons; which physical yard hull 260 was built on is a documented ambiguity, not a contradiction in corporate identity. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-03
-
[4]Patrol Craft Sailors Association (PCSA), 'WWII SCs' page - 'SCs LOST OR DAMAGED' casualty table (verified live 2026-10-03) [other_primary]
- Locator
- ww2pcsa.org/subchaser.html, 'SCs LOST OR DAMAGED' table, row 'SC 633'
- Finding type
- vessel_history
- Finding
- The Patrol Craft Sailors Association's compiled casualty table lists: 'SC 633 | Grounded At Palau Islands | 1944' - placing this hull aground in the Palau Islands during 1944, consistent with her credited participation in the capture and occupation of the southern Palau Islands (6 Sep - 14 Oct 1944 window, see ev-05). The entry does not state the degree of damage; her subsequent September 1945 operation credit indicates she returned to service.
- Verification
- partial
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 1944
- Population
- Crew aboard at grounding (1944)
- Limitations
- Veteran-organization compilation (PCSA) - reasonably authoritative for SC casualties but secondary: gives no exact date, location within the Palaus, casualty severity, or salvage record. A grounding in the Palau group during the Sep-Oct 1944 operation window is consistent but not proven to be the Peleliu/Angaur operation itself. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-04
-
[5]WWII campaign participation credits compiled from Navy and Marine Corps Awards Manual NAVPERS 15,790 (Rev. 1953), SC 633 entry; operation codes corroborated against HyperWar transcription of the same manual (ibiblio.org/hyperwar/USN/ships/dafs/BattleStars.html + Awards-IV part IV) [other_primary]
- Locator
- officialmilitaryribbons.com SC 497 to SC 691 page, 'SC 633' block; HyperWar USN/ships/dafs/BattleStars.html Part III engagement list (P30-2, P207-15 definitions)
- Finding type
- vessel_history
- Finding
- SC-633 is credited with two WWII operations under the campaign-star system: P30-2, capture and occupation of the southern Palau Islands (6 Sep 1944 - 14 Oct 1944), and P207-15, Van Diemen Straits, Kyushu-Korea area (15 Sep 1945 - 18 Sep 1945) - post-surrender occupation-era minesweeping-support work in the straits between Kyushu and Korea. The operation definitions/dates corroborate against the HyperWar transcription of NAVPERS 15,790: P30-2 'Capture and occupation of southern Palau Islands, 6Sep-14Oct44'; P207-15 'Van Dieman Straits (Kyushu-Korea Area), 15Sep-1Dec45' (SC-633's credited window 15-18 Sep 45 falls within the operation window).
- Verification
- partial
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 1944-1945
- Population
- Crew during credited operations (Sep-Oct 1944; Sep 1945)
- Limitations
- Secondary reproduction of the official awards manual (commercial ribbon vendor site) - the underlying assignments trace to NAVPERS 15,790 but the per-hull pages were not verified against a primary scan of the manual's ship lists this session. Campaign credits establish operational presence in credited windows only; they are not day-by-day service records and do not establish where she was between or outside the windows. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-05
-
[6]Naval Historical Center (NHC/NHHC predecessor), 'Typhoons and Hurricanes: Pacific Typhoon at Okinawa, October 1945' - vessel casualty list compiled from Commander in Chief, U.S. Pacific Fleet and Pacific Ocean Areas Report, Serial 0395 of 11 February 1946 (archived copy; live NHHC page returned 404) [other_primary]
- Locator
- Wayback capture of history.navy.mil faqs/faq102-6.htm, vessel listing anchored table (SC rows) - source: CINCPAC Report Serial 0395, 11 Feb 1946
- Finding type
- historical_record
- Finding
- NEGATIVE FINDING on disposal circumstances: the official CINCPAC-compiled casualty list for Typhoon 'Louise' at Buckner Bay, Okinawa (9 October 1945) - 12 sunk, 222 grounded, 32 severely damaged - was checked in full this session. SC-633 does NOT appear on it (SCs listed: 275, 454, 606, 686, 716, 727, 995, 996, 999, 1012, 1306, 1311, 1314, 1326, 1328, 1338, 1368, 1418, 1461, 1474). The 'destroyed 4 April 1946' disposal therefore is NOT documented as a Typhoon Louise casualty demolition - unlike sister SCs (e.g., SC-636 foundered, SC-1012/SC-1306 grounded beyond repair, wrecks destroyed Dec 1945-Jan 1946) whose losses do appear on the list.
- Verification
- verified
- Role
- negative_finding
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 1945-1946
- Population
- Crew present at disposal (1946), if any
- Limitations
- Absence from the casualty list establishes only that she was not a reported Buckner Bay Louise casualty - it does not establish where she was on 9 October 1945 or the cause/circumstances of her April 1946 destruction. 'Destroyed' is a disposal event; whether she was burned, scuttled, or demolished, and where (western Pacific or elsewhere), is undocumented. Archived NHC page used; live NHHC URL 404s.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-06
-
[7]Splinter Fleet (Theodore R. Treadwell) - SC-497 class facts/specifications; corroborated by uboat.net SC-497 class page and PCSA type sheet [other_primary]
- Locator
- splinterfleet.org facts-and-specifications and home page; uboat.net class/464; ww2pcsa.org/subchaser.html type sheet
- Finding type
- vessel_history
- Finding
- SC-497-class context: 438 wooden-hulled 110-foot submarine chasers completed 1941-44 (475 ordered, 37 cancelled) by roughly 50 small yacht and boat yards on the coasts and Great Lakes - the 'splinter fleet,' the smallest commissioned warships of the U.S. Navy in WWII. Wooden construction was chosen to avoid competing for steel allocated to larger combatants. Standard machinery was twin General Motors diesels on two shafts (16-184A 'pancake' at 1,540 bhp or 8-268A at 880 bhp variants); no steam plant. Class service was antisubmarine patrol/escort plus amphibious landing-control work; 70 were converted to SCC control craft, 8 to PGM gunboats, and ~142 transferred to allies.
- Verification
- verified
- Role
- context
- Documentation level
- class_or_era
- Accessed
- 2026-10-03
- Study period
- 1941-1946
- Population
- SC-497-class crews and construction trades generally (1941-46)
- Limitations
- Class-level background only - the figure 438 completed and the machinery variants are consistent across splinterfleet.org, uboat.net, and PCSA type data, but none of it documents anything installed aboard or done by this specific hull beyond membership in the class. Complement varies by source (27-28); NavSource's hull-specific figure (28) is carried in the record.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-07
-
[8]Era inference built on: NavSource SC-633 specification block (twin GM 16-184A diesels, wooden hull); SC-497-class design documentation (splinterfleet.org, PCSA, uboat.net class data); GAO HRD-80-2 program-level Navy asbestos-use documentation (ev-09) [other_primary]
- Locator
- NavSource specifications block; splinterfleet.org/PCSA class data; GAO HRD-80-2 context
- Finding type
- asbestos_application
- Finding
- A diesel-driven wooden submarine chaser built in 1942 sits inside the Navy's documented asbestos-use era. Era-standard applications aboard a vessel of this type and period were: insulation/lagging on hot diesel exhaust runs through the hull, machinery gaskets and valve/flange packing, electrical insulation, and possibly deck-compound or tile materials in accommodations. As a diesel vessel she carried no boilers or steam plant - the boiler/turbine lagging pathway of steam vessels does not apply; the confined-space dynamic of a 110-foot hull applies to whatever insulation was fitted around the engine room.
- Verification
- inferred
- Role
- supporting
- Documentation level
- class_or_era
- Accessed
- 2026-10-03
- Study period
- 1942-1946
- Population
- Mathis/Trumpy construction trades (1942); crew (1942-46); any disposal/demolition crews (1946)
- Limitations
- Class/era inference only - no hull-specific insulation schedule, material list, work package, or survey was located for SC-633. Names era-standard applications, not confirmed installed materials. No quantity; no manufacturer attribution for this hull. The hull was destroyed in 1946, so no present-day survival question arises.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-08
-
[9]GAO, Navy Efforts To Protect Workers From Asbestos Exposure, HRD-80-2 (Oct 18, 1979) [gao]
- Locator
- GAO product page HRD-80-2 (full text blocked, HTTP 403)
- Finding type
- gov_survey
- Finding
- GAO documented that the Navy used asbestos insulation extensively aboard ships and did not begin substituting alternative insulation materials until the early 1970s - spanning this hull's entire construction (1942) and service life (1942-46).
- Verification
- verified
- Role
- context
- Documentation level
- class_or_era
- Accessed
- 2026-10-03
- Study period
- 1979
- Population
- Navy shipyard workers; asbestos program review
- Limitations
- Program-level documentation; supports era context only, not any fact specific to this hull. Full text not retrieved (gao.gov blocks automated fetch, HTTP 403, confirmed 2026-10-03) - content via product-page description.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-09
-
[10]Batch-8008 search ledger (this record): NavSource hull + index pages; uboat.net; shipbuildinghistory/navalmarinearchive Mathis-Trumpy + pc2 tables; PCSA casualty list; officialmilitaryribbons/NAVPERS-compiled campaign credits; HyperWar Awards manual; NHC Typhoon Louise casualty list (Wayback); NARA deck-log lead; CourtListener (blocked); secondary web litigation sweep [other_primary]
- Locator
- search_ledger rows sl-uss-sc-633-sc633-01 through -12
- Finding type
- historical_record
- Finding
- No qualifying ship-specific asbestos record located: no asbestos survey, abatement contract, hazmat disclosure, or verified litigation naming USS SC-633 / PC-633 was found in the public sources searched (see search_ledger). CAVEAT: CourtListener could not be queried this session - the authenticated helper reported the fleet-wide hourly pace budget (~58 requests/hr shared) exhausted on every attempt (2026-10-03); logged as blocked in the search ledger, not as a negative result. Secondary web sweeps surfaced no qualifying case naming the hull. Destruction circumstances of 4 April 1946 are likewise undocumented - she is absent from the official Typhoon Louise casualty list.
- Verification
- verified
- Role
- negative_finding
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 2026-10-03
- Limitations
- Absence of a located public record does not prove absence of asbestos aboard - era-consistent material aboard a 1942 diesel wooden chaser is reasonable inference but not ship-proven; and the litigation repository search is a genuine open gap (throttled, not run). Deck logs and any BuShips disposal file are undigitized leads. Does not establish or defeat any claim of exposure or legal eligibility.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-10
-
[11]NARA RG 24 deck logs (USS PC-633 / SC-633, Sep 1942 - 1946) per PCSA/splinterfleet.org information-sources pages pointing researchers to NARA College Park holdings; PCSA collection archive index (BCHS museum PDF) lists per-hull files by hull number [other_primary]
- Locator
- catalog.archives.gov hull search (unfetchable); splinterfleet.org/information-sources/; ww2pcsa.org patrol-craft archive index
- Finding type
- historical_record
- Finding
- Undigitized archival leads for this hull's service record: WWII deck logs for PC-633/SC-633 (Sept 1942 through her 1946 destruction) are held in NARA RG 24 at College Park per the standard subchaser information-source guidance (splinterfleet.org 'Subchaser Information Sources'; PCSA), but are not publicly digitized - the catalog.archives.gov hull search returned no directly fetchable SC-633 record from this session. The PCSA maintains a patrol-craft archive indexed by hull number. Either could resolve her day-to-day service record, the 1944 Palau grounding details, and her 1946 destruction circumstances.
- Verification
- partial
- Role
- archival_lead
- Documentation level
- ship_specific
- Accessed
- 2026-10-03
- Study period
- 1942-1946 (records); 2026 (access attempt)
- Limitations
- Archival lead only: existence of deck logs is inferred from standard RG 24 holdings for commissioned USN vessels of the period - no SC-633-specific NARA catalog record was retrieved (catalog UI is JS-rendered and unfetchable from this session). No asbestos content expected; leads target service/disposal gaps, not exposure documentation.
- Atlas source
- true
- Evidence ID
- ev-uss-sc-633-sc633-11