The Ring,backup, cataloged under National Stock Number 1620-00-718-6778, is classified within Federal Supply Class 1620 (Aircraft Landing Gear Components) of the Aircraft Components and Accessories group. The manufacturer of record is Goodrich Aerospace Canada Ltd. Government technical data includes 1 specification, cited from the U.S. Government catalog. The record lists 1 manufacturer part number 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 1620-00-718-6778 |
| Primary Part Number | 5172-5 |
| Item Name | Ring,backup |
| FSC / FSG | 1620 / 16 — Aircraft Landing Gear Components |
| Manufacturer | Goodrich Aerospace Canada Ltd |
| Status | ACTIVE |
| General Characteristics Item Description | RING MUST BE UNCUT; 3.744 INCHES MINIMUM,3.746 INCHES MAXIMUM OUTSIDE DIAMETER; 3.496 INCHES MINIMUM,3.500 INCHES MAXIMUM INSIDE DIAMETER IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL B — Remove Demilitarization Key Points |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 5172-5 PRIMARY | Goodrich Aerospace Canada Ltd (CAN) |
| Reference | Meaning |
|---|---|
| 1620AC1-029-3 | 5/2 Secondary reference U.S. Government activity |
NSN 1620-00-718-6778 is a Ring,backup, manufactured by Goodrich Aerospace Canada Ltd, classified under FSC 1620, Aircraft Landing Gear Components. Status: active.
NSN 1620-00-718-6778 has 1 manufacturer part number on file: 5172-5 (Goodrich Aerospace Canada Ltd).
3 possible matches (shared part number, not a government interchangeability claim): 2940-01-444-6730, 8345-01-590-1721, 8345-01-590-2843. Verify interchangeability with system specifications before substitution.
Key specifications for 5172-5: General Characteristics Item Description: RING MUST BE UNCUT; 3.744 INCHES MINIMUM,3.746 INCHES MAXIMUM OUTSIDE DIAMETER; 3.496 INCHES MINIMUM,3.500 INCHES MAXIMUM INSIDE DIAMETER IN; End Item Identification: ACFT NOSE LANDING GEAR. 1 specification is 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 1620-00-718-6778 has DEMIL Code B. 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.