The Diaphragm Assy,valv, cataloged under National Stock Number 1660-00-021-1024, is classified within Federal Supply Class 1660 (Aircraft Air Conditioning, Heating, and Pressurizing Equipment) of the Aircraft Components and Accessories group. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Item Name | Diaphragm Assy,valv |
| FSC / FSG | 1660 — Aircraft Air Conditioning, Heating, and Pressurizing Equipment (FSG 16) |
| Parameter | Value |
|---|---|
| NSN | 1660-00-021-1024 |
| Item Name | Diaphragm Assy,valv |
| FSC / FSG | 1660 / 16 — Aircraft Air Conditioning, Heating, and Pressurizing Equipment |
| Status | ACTIVE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Reference | Meaning |
|---|---|
| 99478-1 | C/1 Advisory reference — outside the item-of-supply concept Honeywell International Inc. Div Aerospace - Torrance |
| 99478-1 | 5/9 Secondary reference Alliedsignal Inc Dba Allied-Signal Aerospace Co |
| 99478-1 | 3/2 Design control — primary reference U.S. Government activity |
NSN 1660-00-021-1024 is a Diaphragm Assy,valv, classified under FSC 1660, Aircraft Air Conditioning, Heating, and Pressurizing Equipment. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5305-01-696-4437. Verify interchangeability with system specifications before substitution.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
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.