The Washer,shroud, cataloged under National Stock Number 1660-00-522-5946, is classified within Federal Supply Class 1660 (Aircraft Air Conditioning, Heating, and Pressurizing Equipment) of the Aircraft Components and Accessories group. The manufacturer of record is Ontic Engineering & Manufacturing, Inc Dba Ontic Us. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | Washer,shroud |
| FSC / FSG | 1660 — Aircraft Air Conditioning, Heating, and Pressurizing Equipment (FSG 16) |
| Manufacturers | Leonardo Spa Aeronautics Division - Torino Site (CAGE A0019); Ontic Engineering & Manufacturing, Inc Dba Ontic Us (CAGE 45934) |
| Parameter | Value |
|---|---|
| NSN | 1660-00-522-5946 |
| Primary Part Number | 511618 |
| Item Name | Washer,shroud |
| FSC / FSG | 1660 / 16 — Aircraft Air Conditioning, Heating, and Pressurizing Equipment |
| Manufacturer | Ontic Engineering & Manufacturing, Inc Dba Ontic Us |
| Status | ACTIVE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Part Number | Manufacturer |
|---|---|
| HS511618 | Leonardo Spa Aeronautics Division - Torino Site (ITA) |
| 511618 PRIMARY | Ontic Engineering & Manufacturing, Inc Dba Ontic Us (USA) |
| 511618 | Leonardo Spa Aeronautics Division - Torino Site (ITA) |
| Reference | Meaning |
|---|---|
| 511618 | 3/9 Design control — primary reference Hamilton Sundstrand Corporation Dba Collins Aerospace |
NSN 1660-00-522-5946 is a Washer,shroud, manufactured by Ontic Engineering & Manufacturing, Inc Dba Ontic Us, classified under FSC 1660, Aircraft Air Conditioning, Heating, and Pressurizing Equipment. Status: active.
NSN 1660-00-522-5946 has 3 manufacturer part numbers on file: HS511618 (Leonardo Spa Aeronautics Division - Torino Site), 511618 (Ontic Engineering & Manufacturing, Inc Dba Ontic Us), 511618 (Leonardo Spa Aeronautics Division - Torino Site).
1 possible match (shared part number, not a government interchangeability claim): 5935-01-182-1250. 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.