Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4804315 | Composite helicopter swashplate | Donald L. Ferris, Lawrence Varholak | 1989-02-14 |
| 4797064 | Composite helicopter rotor hub | Donald L. Ferris | 1989-01-10 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4804315 | Composite helicopter swashplate | Donald L. Ferris, Lawrence Varholak | 1989-02-14 |
| 4797064 | Composite helicopter rotor hub | Donald L. Ferris | 1989-01-10 |