Evidence
8 evidence entries recorded; each entry has a stable permalink (#ev-1 … #ev-8).
-
[1]U.S. Navy Bureau of Ships, Naval Vessel Register, NAVSHIPS 18-1-11 (1 January 1949), digitized scan hosted by General Staff [other_primary]
- Locator
- Printed p. 236, YTB-518 HISADA row (PDF page 237); column headings on same page
- Finding type
- vessel_history
- Finding
- The Bureau of Ships Naval Vessel Register of 1 January 1949 lists YTB-518 HISADA on printed page 236. Its original-construction completion column gives August 1945; its vessel-status column says ACT, status code 1, establishing active Navy service at the register date.
- Verification
- verified
- Role
- supporting
- Documentation level
- ship_specific
- Accessed
- 2026-09-24
- Study period
- 1945-1949
- Limitations
- The register establishes identity, original-construction completion month, and status as of 1 January 1949. ACT is a register status, not a commissioning date. The page does not identify builder, crew, propulsion, asbestos, later service, or final fate.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-01
-
[2]National Archives, Special List 44, U.S. Navy Ships' Deck Logs, by Ship Number [other_primary]
- Locator
- PDF p. 136, YTB-518 (Hisada) row
- Finding type
- historical_record
- Finding
- NARA Special List 44 identifies a YTB-518 (Hisada) logbook interval of 1 January through 31 March 1947.
- Verification
- verified
- Role
- supporting
- Documentation level
- ship_specific
- Accessed
- 2026-09-24
- Study period
- 1947-01-01 to 1947-03-31
- Limitations
- This is a finding-aid entry for a dated logbook interval, not a review of the logbook itself. NARA cautions that deck logs provide no direct evidence of asbestos materials; the list establishes neither activities in the interval nor exposure.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-02
-
[3]U.S. Navy, All Hands, May 1961, 'Memorial Day—Throughout' [other_primary]
- Locator
- Article 'Memorial Day—Throughout,' paragraph naming Hisada and Yokosuka; indexed official PDF text
- Finding type
- vessel_history
- Finding
- A U.S. Navy All Hands article in the May 1961 issue identifies Hisada (YTB 518) as a large harbor tug operating from Yokosuka Naval Base and says it took part in a Memorial Day observance in Tokyo Bay in the preceding year.
- Verification
- partial
- Role
- supporting
- Documentation level
- ship_specific
- Accessed
- 2026-09-24
- Study period
- 1960-1961
- Limitations
- Official PDF text was indexed and readable in search results, but direct PDF retrieval returned HTTP 403, so its printed page number was not independently checked. The article supports the historical Yokosuka assignment and ceremony, not continuous basing, asbestos, or crew exposure.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-03
-
[4]Naval Sea Systems Command, Ship History, 28 June 2011 [other_primary]
- Locator
- Indexed PDF text, p. 105, row 'YTM 0518 | HISADA | 18-May-76 | TARGET'
- Finding type
- vessel_history
- Finding
- A NAVSEA historical ship roster lists YTM 0518 HISADA, removal date 18 May 1976, and final-disposition code TARGET.
- Verification
- partial
- Role
- supporting
- Documentation level
- ship_specific
- Accessed
- 2026-09-24
- Study period
- 1976
- Limitations
- Direct PDF retrieval returned HTTP 403; row was checked in the search engine's indexed text only. 'Removal' is the table's label and is not here converted into a decommissioning or striking date. TARGET is a disposition code and alone does not prove when or whether the hull was sunk, nor what materials it contained at disposal.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-04
-
[5]Naval History and Heritage Command, Dictionary of American Naval Fighting Ships, 'Accohanoc (YTB-545)' [nhhc_danfs]
- Locator
- Vessel specifications header, 'class Hisada'
- Finding type
- historical_record
- Finding
- NHHC identifies Accohanoc (YTB-545) as a Hisada-class harbor tug. This establishes a Navy-used class label but is not a construction or materials record for Hisada herself.
- Verification
- verified
- Role
- context
- Documentation level
- class_or_era
- Accessed
- 2026-09-24
- Study period
- 1940s
- Limitations
- A sister's DANFS entry supports class nomenclature only. Its complement and other specifications are not transferred to Hisada; it says nothing about asbestos on either hull.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-05
-
[6]National Archives, 'Researching Asbestos aboard US Naval Vessel up through 1961' [other_primary]
- Locator
- RG 19 and Cartographic Branch sections, especially S39 and 19-Hull / 19-Micro
- Finding type
- historical_record
- Finding
- NARA's shipboard asbestos guide identifies RG 19 Bureau of Ships hull correspondence, ship specifications, and ship engineering drawings organized by hull number, especially S39 insulation and lagging, as leads for testing whether Hisada had asbestos-containing materials.
- Verification
- verified
- Role
- archival_lead
- Documentation level
- context_only
- Accessed
- 2026-09-24
- Study period
- 1945-1976 records
- Limitations
- NARA identifies possible record series, not an existing Hisada file or finding. No box-level retrieval, reproduction, or material identification was performed.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-08
-
[7]Batch 9433 source review and search ledger [other_primary]
- Locator
- Search-ledger rows sl-uss-hisada-ytb518-01 through -07; BATCH-9433-REPORT.md
- Finding type
- historical_record
- Finding
- No qualifying publicly accessible ship-specific asbestos document was located in the 1949 register, NARA Special List 44, the indexed 1961 All Hands article, or the indexed NAVSEA disposition table. The CourtListener opinion and docket sweep was blocked by fleet pacing before results could be returned; it is not counted as a negative litigation result.
- Verification
- partial
- Role
- negative_finding
- Documentation level
- ship_specific
- Accessed
- 2026-09-24
- Study period
- 2026-09-24
- Limitations
- This is a bounded negative finding for the accessible sources actually checked, not evidence that asbestos was absent. Primary plans, specifications, surveys, logs, and litigation databases remain incompletely searched. The CourtListener helper returned only a pacing stand-down, never a case result.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-07
-
[8]National Archives, 'Researching Asbestos aboard US Naval Vessel up through 1961' [other_primary]
- Locator
- Beginning Research; RG 19 correspondence; Cartographic Branch, S39 Insulation and Lagging; Other Records and their usefulness
- Finding type
- asbestos_application
- Finding
- NARA identifies asbestos use in U.S. Navy materiel during 1941–1961 as a research subject and directs researchers to ship-specific Bureau of Ships correspondence, specifications, and engineering drawings, including S39 insulation and lagging records, to establish materials on a particular hull.
- Verification
- verified
- Role
- supporting
- Documentation level
- class_or_era
- Accessed
- 2026-09-24
- Study period
- 1941-1961
- Population
- U.S. Navy ships of the 1941–1961 period (research context)
- Limitations
- The NARA guide describes an era-level research problem and archival method; it does not name Hisada, her class, or any asbestos product installed aboard her. It cannot support ship-specific presence, location, amount, exposure, or causation.
- Atlas source
- true
- Evidence ID
- ev-uss-hisada-ytb518-06