The Duct Assembly,air Conditioning-H, cataloged under National Stock Number 1660-01-274-9590, is classified within Federal Supply Class 1660 (Aircraft Air Conditioning, Heating, and Pressurizing Equipment) of the Aircraft Components and Accessories group. Government technical data includes 2 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 1660-01-274-9590 |
| Item Name | Duct Assembly,air Conditioning-H |
| FSC / FSG | 1660 / 16 — Aircraft Air Conditioning, Heating, and Pressurizing Equipment |
| Status | ACTIVE |
| Aircraft Location | ECS RETROFIT MISSILE CONDITIONING SUB SYSTEM DUCT ASSEMBLY |
| Aircraft Mission Design Series | B-52 |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL Q — CCL Item — Commerce Control List |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 520-10489-20 | 3/2 Design control — primary reference U.S. Government activity |
NSN 1660-01-274-9590 is a Duct Assembly,air Conditioning-H, classified under FSC 1660, Aircraft Air Conditioning, Heating, and Pressurizing Equipment. Status: active.
Key specifications for 1660-01-274-9590: Special Features: INSULATE WITH BMS8-104, TYPE I, GRADE 10AA PER BAC5412, METHOD 1; LEAVE 1.750 FREE OF INSULATION AT ENDS; CONSIST OF ONE DUCT, FOUR DUCT HALVES, ONE INSULATION, ONE PRESS SENSITIVE TAPE, ONE FILLER METAL; NHA 520-10104; Aircraft Location: ECS RETROFIT MISSILE CONDITIONING SUB SYSTEM DUCT ASSEMBLY; End Item Identification: B-52 AIRCRAFT; Aircraft Mission Design Series: B-52. 2 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
NSN 1660-01-274-9590 has DEMIL Code Q. Demilitarization may be required before disposal or transfer to non-military entities.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.