Evidence
11 evidence entries recorded; each entry has a stable permalink (#ev-1 … #ev-11).
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[1]research packet 1027-packet.md [other_primary]
- Finding type
- vessel_history
- Finding
- Identity packet verdict: VERIFIED (thin sourcing on construction dates, disclosed)
- Verification
- verified
- Role
- supporting
- Documentation level
- ship_specific
- Limitations
- qualifier: VERIFIED (thin sourcing on construction dates, disclosed)
- Evidence ID
- uss-yms-103-yms103-pkt-1027-packet-md
-
[2]NARA RG 38 file unit, NAID 139986604 - 'USS YMS-103 - Report of operations in the invasion of Okinawa Jima, Ryukyu Islands, 4/2-8/45, including striking of mines & beaching on 4/8/45' (Micro Serial 119415; Serial 001; dated 4/25/1945; Roll A1567; 15 digitized images) [other_primary]
- Locator
- NARA NAID 139986604, file-unit title and Parts I-VIII; transcription https://yms299.org/archives/493
- Finding type
- vessel_history
- Finding
- The ship's own surviving primary record. CO L.M. Thornton, LTJG USNR, submits the Okinawa-operation action report to CINC U.S. Fleet (dated 25 April 1945). Part I: en route Saipan to Okinawa Gunto as escort for TU 51.13.4 (6 Mar - 2 Apr); Kerama Retto arrival ~1000 2 Apr; joined TU 52.7.2 4 Apr sweeping inside the 100-fathom curve; two contact mines swept 5 Apr; mine-disposal duties 6 Apr (seven mines destroyed/sunk); three mines 7 Apr and shore-battery engagement near China Saki; 8 Apr - PGM-18 mined ~0743 and sank 0805; YMS-103 ordered to aid survivors at 0750, first mine blew bow off to forward edge of bridge at 0808, second mine sheared hull to generator compartment at 0813; abandon ship ordered; CO left ship 0820; survivors recovered by 0950 by boats of YMS-103, YMS-92, and an AM, medical aid by USS Lindsey and YMS-92; hulk towed by ATF-84 and beached in U.S.-held territory; classified publications, pay accounts, and service records saved; machinery spares salvaged. Part V details damage by mine. Part VII accounts 27 survivors (3 officers, 24 men), 5 KIA, 0 missing, and names the dead: Lt.(jg) James Robert Davidson USNR; MM2c Oscar Francis Cardoza USNR; SoM2c Albert Marvin McKinney USN; CMoMM(T) Jack Ellsworth Savage USNR; S1c Clarence Leonard Smith USNR - all buried at sea. Introduction states 'all logs and communication records of the U.S.S. YMS-103 were lost.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-03-06 to 1945-04-25
- Population
- Crew (32: 4 officers + 28 men) and PGM-18 survivors being rescued, 8 April 1945
- Limitations
- Primary source for the loss narrative and casualty accounting only - no asbestos or material content. Digitized images available via NARA/Fold3; public full-text transcription at yms299.org corroborates page-for-page. Wounded are described qualitatively ('severely injured several men'), not enumerated; secondary compilations citing 'seven wounded' are not itemized in this document.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-01
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[3]NavSource Online: Mine Warfare Vessel Photo Archive, YMS-103 (11/19103) - timeline, specifications, commanding-officer list, action-report image set, crew/muster-roll and press-article photo captions; explicit 'There is no DANFS history available for YMS-103' [other_primary]
- Locator
- NavSource 11/19103.htm header timeline, specifications block, CO table, photo-caption table
- Finding type
- vessel_history
- Finding
- NavSource timeline for this hull: laid down 22 July 1941 by Astoria Marine Construction Co., Astoria, OR; launched 29 August 1942; commissioned 19 September 1942; 'damaged by mines 7 April 1945' in Nakagusuku-wan (Buckner Bay), Okinawa; beached 8 April 1945, decommissioned and abandoned; struck from the Navy list 19 May 1945. Specifications: displacement 320 t., length 136', beam 24' 6", draft 6' 1", speed 13 kts., complement 32; armament one 3"/50 DP mount, two 20mm mounts, two depth-charge tracks and two depth-charge projectors; propulsion two 880 bhp General Motors 8-268A diesel engines, Snow and Knobstedt single reduction gear, two shafts. Call sign Nan - Able - How - Yoke. Commanding officers: LT Carl R. Cunningham, Jr., USNR (19 Sep 1942); LTJG L. M. Thornton, USNR (1945). Photo captions document a crew collection (SM1c Howard Rider), the muster roll ending 31 March 1945, a 'Minesweeper Does Vital But Humdrum Job' article, and United Press and International News Service articles on the sinking.
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1941-1945
- Population
- Construction trades (Astoria, 1941-42); crew (1942-45)
- Limitations
- NavSource is a volunteer secondary compilation - its '7 April' mining date conflicts with the ship's action report and the official Navy chronology, both of which place the loss on 8 April (see ev-05 correction row). The press articles and muster roll exist only as page images - not OCR-verified here. Contains no asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-02
-
[4]United States Naval Chronology, World War II (Naval History Division / ONI chronology), April 1945 section - HyperWar transcription at ibiblio.org [other_primary]
- Locator
- chr45-04.html, '04/08 Sun.' entry, damaged-list and sunk-list items
- Finding type
- historical_record
- Finding
- Under the 04/08 (Sunday) entry: 'United States naval vessel sunk: Motor gunboat PGM-18, by mine, Okinawa area, 26 d. 13'N., 127 d. 55'E.' and 'United States naval vessels damaged, Okinawa area: ... Motor minesweeper YMS-103, by mine, 26 d. 13'N., 127 d. 54'E.' The official chronology dates the YMS-103 mine event 8 April 1945 and classifies her as damaged rather than sunk - consistent with the action report's account of a beached, abandoned total loss rather than a sinking.
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-04-08
- Population
- Crew and PGM-18 survivors, 8 April 1945
- Limitations
- HyperWar is a volunteer transcription of the official Navy chronology, not the issuing office itself; content is a casualty-list entry only - a one-line event record with position, no narrative, no material or asbestos content. The 'damaged' classification does not capture that she was a constructive total loss.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-03
-
[5]YMS-299 memorial site - 'YMS-103 Action Report; April 25, 1945': full-text transcription plus scanned page images of CO L.M. Thornton's action report, provided by Richard Thornton (the CO's son); companion 8 April 1945 journal entry from the YMS-299 collection [other_primary]
- Locator
- yms299.org/archives/493 (transcript + page scans); yms299.org/archives/706 (8 Apr 1945 journal entry)
- Finding type
- historical_record
- Finding
- Full public transcription of the action report (same document as NARA NAID 139986604): serial YMS103/A16-3 Serial 001, dated 25 April 1945, via YMS Type Commander PacFlt / ComMinecraft PacFlt / CTF 52 / ComPhibPac / CTF 5th Flt / CinCPac to CominCh. Transcription verifies the loss narrative and Part VII named-casualty accounting (5 KIA, 27 survivors, 0 missing; dead buried at sea). A companion dated journal entry from a YMS-299 crewman records survivor boats from 'AM-15' picking up 'sixteen - or half of the crew of the YMS-103' - an eyewitness complement to the official accounting.
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-04-02 to 1945-04-25
- Population
- Crew (32) and rescuing craft crews, 8 April 1945
- Limitations
- Private memorial site (descendants of YMS-299's crew) hosting transcriptions and scans of an official document - corroborated against the NARA file-unit record, but the site itself is a secondary repository. The journal entry is a personal account: its 'AM-15' identification and 'half the crew' phrasing are eyewitness color, not official accounting. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-04
-
[6]Date conflict documented: NavSource timeline ('damaged by mines 7 April 1945') and uboat.net history line ('Mined and damaged on 7 April 1945 ... Beached the next day') vs the ship's action report (explosions 0808 and 0813 on 8 April 1945, after PGM-18 sank at 0805) and the official Navy casualty chronology (event filed under 04/08) [other_primary]
- Locator
- uboat.net ship/9523 history block; NavSource 11/19103.htm timeline; NARA NAID 139986604 Part I; chr45-04.html 04/08 entry
- Finding type
- historical_record
- Finding
- CORRECTION: NavSource's timeline bullet and uboat.net's history line both date the mining to 7 April 1945; uboat.net is internally inconsistent (Loss field 8 Apr 1945; history text 'mined ... 7 April ... beached the next day'). The primary record is unambiguous: the action report's own narrative places PGM-18's explosion ~0743 and YMS-103's two mine explosions at 0808 and 0813 on 8 April 1945, and the official Navy casualty chronology files the event under 04/08. On 7 April YMS-103 swept three mines and was straddled by a ~75mm shore battery near China Saki but was NOT damaged. Record carried: mined and beached 8 April 1945.
- Verification
- verified
- Role
- correction
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1945-04-07 to 1945-04-08
- Limitations
- Corrects a circulating one-day date error in two secondary timelines; not a material claim. uboat.net's ordered date of 1 April 1941 is secondary-only and is carried in gaps, not asserted. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-05
-
[7]NARA RG 24 file unit, NAID 193168703 - 'YMS-103, 9/5/42-5/14/45' (Muster Rolls of U.S. Navy Ships, Stations, and Other Naval Activities; Roll 8067); plus NARA-cataloged deck logs 9/19/1942-8/31/1944 (Logbooks of U.S. Navy Ships and Stations) [other_primary]
- Locator
- NARA NAID 193168703 (RG 24, Roll 8067); Logbooks series catalog range 9/19/1942-8/31/1944
- Finding type
- historical_record
- Finding
- Archival holdings for this hull: muster rolls spanning 5 September 1942 - 14 May 1945 (crew assignment/pay records, roll 8067), and deck logs covering 19 September 1942 - 31 August 1944. The action report explains the coverage boundary: 'all logs and communication records of the U.S.S. YMS-103 were lost' in the sinking - logs after the last forwarded set went down with the ship. Muster rolls and deck logs are the open leads for the undocumented 1942-44 service period (stations, availabilities, and any material/work records).
- Verification
- partial
- Role
- archival_lead
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1942-1945
- Population
- Crew, 1942-1945 (muster/deck-log subjects)
- Limitations
- Archival lead only: holdings identified by catalog metadata; page contents not reviewed here, and no asbestos or material content is asserted from them. The deck-log date range is per the NARA catalog index as supplied in the batch assignment - per-month file units were not individually surfaced in this session's catalog search. Whether the rolls/logs themselves discuss materials or availabilities is unknown.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-06
-
[8]Era inference built on: NavSource spec block (2 x GM 8-268A diesels, no steam plant; wooden hull) and class references describing the YMS-1 class as wooden-hulled coastal minecraft built at 35 small yacht yards; GAO HRD-80-2 Navy-wide asbestos-era documentation [other_primary]
- Locator
- NavSource 11/19103.htm specifications block; NavSource YMS index class description; GAO HRD-80-2 product page
- Finding type
- asbestos_application
- Finding
- A wooden-hulled diesel-powered small craft of 1941-42 construction sits inside the Navy's documented asbestos-use era, but the exposure surface is materially smaller than a steam vessel's: no boilers, no steam drums, no steam-line lagging. Era-standard applications aboard a minesweeper of this type and period were diesel exhaust lagging and silencer insulation, engine and machinery insulation, flange gaskets, valve packing, electrical insulation, brake linings on winch/windlass gear, and incidental fireproofing - compact quantities concentrated in the small engine-room volume.
- Verification
- inferred
- Role
- supporting
- Documentation level
- class_or_era
- Accessed
- 2026-10-04
- Study period
- 1941-1945
- Population
- Astoria Marine construction trades (1941-42); crew (1942-45); salvage/survey personnel on the beached hulk (Apr 1945)
- Limitations
- Class/era inference only - no hull-specific insulation survey, material list, or work package located for YMS-103. Names era-standard applications, not confirmed installed materials. No quantity. Product names are normalized era terms; no manufacturer attribution for this hull.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-07
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[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 (1941-42) and service era (1942-45).
- 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. Full text not retrieved (gao.gov blocks automated fetch, HTTP 403, confirmed 2026-09-18 batch precedent) - content via product-page description.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-08
-
[10]CourtListener API v4 via cl-auth-search.py - the required 4 base queries ("USS YMS-103" type=o and type=r; "YMS-103" type=o and type=r, --limit 20) could not be executed this session: the fleet-wide pacing limiter stood down every attempt (budget momentarily spent - shared ~58/hr across concurrent sessions) [court_record]
- Locator
- search_ledger row sl-uss-yms-103-yms103-09
- Finding type
- litigation_documented
- Finding
- Litigation repository unsearched (blocked, not a negative result): CourtListener base queries attempted repeatedly this session; the fleet pacing limiter returned stand-down guidance on every attempt. Secondary web sweeps surfaced no qualifying asbestos case naming this hull - only excluded law-firm marketing content. Re-run list (next session with budget): "USS YMS-103" (o, r), "YMS-103" (o, r), --limit 20.
- Verification
- unverified
- Role
- archival_lead
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 2026-10-04
- Limitations
- This row records an access gap, not a finding: no litigation conclusion may be drawn. The open question is whether any docketed case names this hull - not whether asbestos was aboard.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-09
-
[11]Batch-8779 search ledger (this record): NARA catalog (action report, muster rolls, deck-log index range); NavSource; yms299.org memorial archive; ibiblio/HyperWar Navy chronology; uboat.net; NHHC/DANFS check; NVR check; shipyards.json cross-check; secondary web litigation sweep; CourtListener (status as logged) [other_primary]
- Locator
- search_ledger rows sl-uss-yms-103-yms103-01 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 YMS-103 was found in the public sources searched. This is unsurprising for the hull's profile - a small wooden minesweeper built at a yacht yard, lost to mines in 1945, with no post-service physical existence to survey or abate. Law-firm marketing content asserting asbestos aboard generic 'YMS' vessels exists but is excluded by source policy. CourtListener status is as logged in the search ledger (completed or blocked - see sl-09).
- 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 - era-consistent inference still stands. Does not establish that asbestos is or is not present; does not establish or defeat any claim of exposure or legal eligibility.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-103-yms103-10