Evidence
13 evidence entries recorded; each entry has a stable permalink (#ev-1 … #ev-13).
-
[1]research packet 970-packet.md (2 sources cited) [other_primary]
- Finding type
- vessel_history
- Finding
- Identity packet verdict: MISMATCH
- Verification
- verified
- Role
- correction
- Documentation level
- ship_specific
- Evidence ID
- uss-yms-481-pkt-970-packet-md
-
[2]NavSource Online: Mine Warfare Vessel Photo Archive, YMS-481 (ex-PCS-1463) - milestones, specifications, loss, striking (verified live on navsource.net 2026-10-04; navsource.org domain is dead) [other_primary]
- Locator
- NavSource 11/19481.htm header block, milestone lines, specifications block
- Finding type
- vessel_history
- Finding
- Milestones for this hull: laid down 25 May 1943 as patrol craft sweeper by the Bellingham Marine Railway and Boatbuilding Co., Bellingham, WA; reclassified auxiliary motor minesweeper YMS-481 on 27 September 1943; launched 20 November 1943; completed 15 March 1944; sunk by shore batteries off Tarakan, Borneo, 2 May 1945; struck from the Naval Register 2 June 1945. Specifications: displacement 270 t; length 136'; beam 24'6"; draft 8'; speed 15 kts; complement 32; armament one 3"/50 dual-purpose mount, two 20mm mounts, two depth-charge projectors; propulsion two 880shp GM 8-268A diesels, Snow and Knobstedt reduction gear, two shafts. Page explicitly states 'There is no DANFS history available for YMS-481' and holds no photograph of the hull.
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1943-1945
- Population
- Bellingham construction trades (1943-44); crew (1944-45)
- Limitations
- Volunteer secondary compilation, not a primary registry - milestone dates generally track NVR-derived data. Internal inconsistency on this page: the header reads 'ex-PCS-1463' but the body text prints 'PCS-1462' - the 1462 number belongs to YMS-480 (see ev-07). Contains no asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-01
-
[3]NHHC H-Gram 051-1, 'The Last Sacrifices' (Director's Corner, Naval History and Heritage Command) - Tarakan Operation Oboe 1 narrative [nhhc_danfs]
- Locator
- H-Gram 051-1, 'Tarakan: Operation Oboe 1, April-May 1945' section
- Finding type
- vessel_history
- Finding
- Official NHHC operational history of the Tarakan minesweeping operation: sweepers and covering force arrived off Tarakan 27 April 1945, with USS Cofer (APD-62) as flagship and mothership for the minesweepers and UDTs; on 30 April the destroyer USS Jenkins, operating in a previously swept channel, struck a mine and was damaged. 'On 2 May 1945, a carefully concealed Japanese shore battery of two 75mm guns at Tarakan opened up and hit three of the minesweepers in quick succession. Auxiliary motor minesweeper YMS-481 sank, with a loss of six of her crewmen, and YMS-364 suffered significant damage. Cofer rescued 18 survivors and silenced the Japanese battery for the time being, but it continued to fire sporadically on U.S. ships until the destroyer escort Douglas A. Munro (DE-422) finally knocked it out for good on 23 May.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-04-27 to 1945-05-23
- Population
- Crew of YMS-481 (6 killed, ~26 survivors); Cofer rescue party
- Limitations
- Ship-specific official operational history; establishes the loss, the six-killed casualty figure, and the 18-survivor rescue by Cofer - but is not a loss report and names no casualty. Contains no asbestos or material content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-02
-
[4]NHHC, 'Casualties: U.S. Navy and Coast Guard Vessels, Sunk or Damaged Beyond Repair during World War II' - Motor Mine Sweepers (YMS) listing [nhhc_danfs]
- Locator
- Motor Mine sweepers (YMS) section, alphabetical listing
- Finding type
- vessel_history
- Finding
- The official NHHC WWII loss list records: 'USS YMS-481 sunk by shore batteries off Tarakan, Borneo, 2 May 1945.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-05-02
- Limitations
- Confirms official classification of the loss (sunk by shore batteries) and date only; no casualty count, no asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-03
-
[5]Robert J. Cressman, The Official Chronology of the U.S. Navy in World War II (NHHC; HyperWar/ibiblio mirror) - 2 May 1945 entry; corroborated by the PHA chronology mirror at ibiblio.org/pha/chr/chr45-05.html [other_primary]
- Locator
- USN-Chron-1945.html, 2 May 1945 entry; chr45-05.html 05/02 entry
- Finding type
- vessel_history
- Finding
- The official chronology records under 2 May 1945: 'Off Tarakan, Borneo, Japanese shore batteries sink motor minesweeper YMS-481'; the PHA mirror lists 'United States naval vessel sunk: Motor minesweeper YMS-481, by coastal defense gun, Tarakan area, Borneo' on the same date.
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-05-02
- Limitations
- Official chronology entry; date and cause only - no further detail. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-04
-
[6]Walter Karig et al., Battle Report: Victory in the Pacific (official U.S. Navy combat narrative, 1949), pp. 265-266 - Internet Archive scan [other_primary]
- Locator
- Battle Report: Victory in the Pacific, pp. 265-266 (djvu.txt stream, Tarakan paragraph)
- Finding type
- historical_record
- Finding
- The official Navy combat narrative of the Tarakan operation records that on the day after the landing, when five sweeps moved into the narrow shallow channel north of Tarakan, at least six previously undetected Japanese shore batteries opened fire: 'YMS 481 took seven direct hits, blew up and sank; and YMSs 334 and 364 also were holed in the brief barrage. But forthwith the fire was returned by the destroyer-transport Cofer and two heavily gunned LCSs, which silenced the Japanese positions before they could reload.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-05-02
- Population
- Crew of YMS-481; sweep unit and rescue craft
- Limitations
- Official popular history, not the action report itself; gives hit count ('seven direct hits', 'blew up and sank') but no casualty count. Internet Archive full text is OCR-scanned - transcription artifacts exist in surrounding text; the passage was verified against the scan. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-05
-
[7]uboat.net Allied Warships of WWII, USS YMS-481 (YMS-481) - build/loss data card and transcribed operation-event narratives (Operation Victor II, Cebu, 24 Mar 1945; Operation Oboe I, Tarakan, Apr-May 1945) [other_primary]
- Locator
- uboat.net ship/9897.html data card; 'Notable events' sections 24 Mar 1945 (Cebu) and 1-2 May 1945 (Tarakan, TG 78.1.5)
- Finding type
- vessel_history
- Finding
- Vessel data card: built by Bellingham Marine Railway and Boatbuilding Co., Bellingham WA; ordered 16 Dec 1942; laid down 25 May 1943; launched 20 Nov 1943; commissioned 15 Mar 1944; lost 2 May 1945 at position 03 deg 27'N, 117 deg 32'E - 'Sunk by Japanese shore batteries off Tarakan, Borneo, Netherlands East Indies.' Event narratives place YMS-481 in the Cebu minesweeping unit (TU 78.2.9, Operation Victor II, 24 Mar 1945) and the Tarakan minesweeping unit (TG 78.1.5, Oboe I) under Lt.(jg) T.D. Anglin, USNR; the Oboe narrative records that at 1530/2 May, camouflaged batteries at Cape Djoeata sank YMS-481 and damaged YMS-334 and YMS-364; USS Cofer and LCS-8/LCS-28 silenced the battery, and LCS-44, LCI(L)-1008 and LCVPs rescued survivors close inshore under direct enemy fire; YMS-51 and YMS-340, sweeping in the same area, were not hit.
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-03-24 to 1945-05-02
- Population
- Crew under Lt.(jg) T.D. Anglin USNR (1945); TG 78.1.5 sweep unit
- Limitations
- Volunteer-compiled secondary database whose event narratives are transcribed from operation orders/action reports; its 'former name' field prints PCS-1462 - an error (1462 was YMS-480; see ev-07). No casualty count; no asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-06
-
[8]NavSource Online, YDG-7 (ex-YMS-480, ex-PCS-1462) page - designation cross-check against NavSource's own sister-hull record; corroborated by the uboat.net YMS-481 data card [other_primary]
- Locator
- NavSource 11/19480.htm (YDG-7 ex-YMS-480 ex-PCS-1462 header and milestone lines) vs NavSource 11/19481.htm (ex-PCS-1463 header / PCS-1462 body text); uboat.net ship/9897 'former name' field
- Finding type
- historical_record
- Finding
- CORRECTION: YMS-481's pre-reclassification designation was PCS-1463, not PCS-1462. NavSource's own YDG-7 page shows PCS-1462 became YMS-480 (laid down at the same yard on the same day, 25 May 1943; reclassified the same day, 27 September 1943; launched the same day, 20 November 1943) - the 'PCS-1462' in the NavSource YMS-481 body text is a copy-paste artifact of the twin pages, and uboat.net's 'former name PCS-1462' repeats the error. YMS-480's record is the correct home of the 1462 number; YMS-481 was ex-PCS-1463 (NavSource header; batch fact-QA).
- Verification
- verified
- Role
- correction
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1943
- Limitations
- Corrects a circulating designation error, not a material or exposure claim. NavSource remains a volunteer secondary compilation; the resolution is internally consistent across its own pages but no primary NVR scan was consulted.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-07
-
[9]Era inference built on: 'Ships of the U.S. Navy, 1940-1945 - Minesweepers' (HyperWar compilation: 'the wood-hulled YMS,' one-stack subclass YMS-135-445/480/481); NavSource specifications (diesel propulsion, wood hull class); shipbuildinghistory.com YMS production table (35 boatyards, 561 wooden-hulled minesweepers; YMS-481 final entry) [other_primary]
- Locator
- HyperWar ships-dm.html YMS class section and YMS-481 loss-table row; NavSource 11/19481.htm specifications; shipbuildinghistory.com/smallships/ym.htm intro and Bellingham block
- Finding type
- asbestos_application
- Finding
- A wood-hulled, diesel-powered auxiliary motor minesweeper built 1943-44 at a small Bellingham boatyard had a far narrower asbestos-relevant inventory than a steam vessel: no boilers, no steam lines, no turbines - so no boiler/steam-line/turbine lagging pathway exists. Era-standard applications aboard a wood-hulled diesel craft of this type and period were limited to diesel-exhaust lagging, gaskets, valve packing, and electrical insulation in machinery spaces. The class was produced by 35 small boat/yacht yards to a common 136-ft design; YMS-481 was the highest-numbered unit completed (YMS-482 through YMS-500 cancelled).
- Verification
- inferred
- Role
- supporting
- Documentation level
- class_or_era
- Accessed
- 2026-10-04
- Study period
- 1943-1945
- Population
- Bellingham construction trades (1943-44); crew of 32 (1944-45)
- Limitations
- Class/era inference only - no hull-specific insulation survey, material list, or work package located for YMS-481. Names era-standard applications, not confirmed installed materials. No quantity, no manufacturer attribution. The wooden-hull/diesel framing reduces but does not eliminate the inference - wood construction does not prove zero asbestos aboard (gaskets, packing, electrical and exhaust applications remained era-typical).
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-08
-
[10]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 (1943-44) and service era (1944-45).
- Verification
- verified
- Role
- context
- Documentation level
- class_or_era
- Accessed
- 2026-10-04
- 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 - and the program-level finding primarily describes insulation aboard larger steam-powered ships, so its weight for a wood-hulled diesel craft is limited. Full text not retrieved (gao.gov blocks automated fetch, HTTP 403 - standing defect since Batch 01) - content via product-page description.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-09
-
[11]Pacific Wrecks, YMS-481 Motor Mine Sweeper - wreck-site entry (position 3 deg 26'N 117 deg 32'E) marking the sunken hull off Tarakan [other_primary]
- Locator
- pacificwrecks.com/ship/usn/YMS-481.html (last updated 2025-12-19)
- Finding type
- historical_record
- Finding
- The wreck-site database documents YMS-481 as a sunken wreck off Tarakan, Borneo, at position 3 deg 26'N, 117 deg 32'E, lost to a Japanese coastal-defense gun - consistent with an unsalvaged war loss; no salvage or demolition record exists for this hull.
- Verification
- partial
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-present (wreck in situ)
- Limitations
- Volunteer wreck-site compilation; it dates the sinking 1 May 1945 - one day earlier than the NHHC/NavSource/chronology consensus of 2 May - and lists variant specs (320 t, 6'1" draft); carried for wreck position and current-status context only. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-10
-
[12]Batch-8380 search ledger (this record): NavSource hull + sister pages; NHHC H-Gram 051-1 and WWII casualties list; official chronology; official Battle Report narrative; uboat.net; Pacific Wrecks; shipbuildinghistory; CourtListener API v4; secondary web litigation sweep [other_primary]
- Locator
- search_ledger rows sl-uss-yms-481-01 through sl-uss-yms-481-13
- Finding type
- historical_record
- Finding
- No qualifying ship-specific asbestos record located: no asbestos survey, abatement contract, hazmat disclosure, or litigation naming USS YMS-481 (or PCS-1463) was found in the public sources searched. CourtListener base queries - 'YMS-481' and 'USS YMS-481' against the opinion and docket indexes (--limit 20) - returned zero results; no qualifying case exists in the index. Secondary web sweeps surfaced only law-firm marketing material (generic minesweeper listicles at mesothelioma.com, mesotheliomahope.com, mesotheliomaveterans.org, mesotheliomalawyercenter.org; a Cofer-page mention of the YMS-481 rescue at asbestos-ships.com) asserting asbestos without primary sourcing - excluded by source policy.
- Verification
- verified
- Role
- negative_finding
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 2026-10-04
- Limitations
- Absence of a located public record does not prove absence of asbestos aboard - a wood-hulled diesel craft of 1943-44 carried era-typical gaskets, packing, and insulation. The litigation negative is strong for this hull: a 14-month combat loss leaves almost no post-service claimant pool, and zero search results across all four base queries is the expected pattern - but deck logs, builder work packages, and the TG 78.1.5 action/loss reports are undigitized leads (see ev-12). Does not establish or defeat any claim of exposure or legal eligibility.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-11
-
[13]NARA leads: RG 24 deck logs for YMS-481 (Mar 1944-May 1945); TG 78.1/78.1.5 action reports and the CO loss report for the Tarakan operation (the uboat.net narratives derive from the Oboe operation record); NARA 19-N builder photography exists for near-sister YDG-7 (19-N-62838, 19-N-62834, per NavSource captions) suggesting a Bellingham builder photo series that may include this hull [other_primary]
- Locator
- NARA RG 24 deck-log series (undigitized for this era); TG 78.1 action-report series; NARA 19-N vessel photographs (19-N-62838/62834 for sister YDG-7 per NavSource captions)
- Finding type
- historical_record
- Finding
- Undigitized primary records for this hull exist at NARA: WWII deck logs for her Mar 1944-May 1945 service (RG 24); the TG 78.1 minesweeping-unit action reports and any commanding-officer loss report for 2 May 1945; and a probable builder-photograph series in RG 19 (the sister hull YDG-7 has 19-N builder photos dated 21 March 1944). These are the records that would settle crew-level, material, and loss detail.
- Verification
- partial
- Role
- archival_lead
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1944-1945
- Population
- Crew (1944-45); TG 78.1.5 unit
- Limitations
- Archival lead only - none of these records was consulted; their existence is inferred from standard Navy record series and the sister-hull photo citations. No asbestos content established.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-481-12