| Number | Name | Date | Kind |
|---|---|---|---|
| 2279812 | Bartlett | Apr 1942 | |
| 2508757 | Gray | May 1950 | |
| 2679254 | Green | May 1954 | |
| 2679255 | Stafford | May 1954 | |
| 2723811 | Blomquist | Nov 1955 | |
| 3044516 | Stoll | Jul 1962 | |
| 3133715 | Grunfelder | May 1964 | |
| 3815650 | Hickey | Jun 1974 | |
| 3971532 | Fountain | Jul 1976 | |
| 4008730 | Keklak et al. | Feb 1977 | |
| 4301982 | Tiemann | Nov 1981 |
| Entry |
|---|
| "Global Chemical Systems Perfects Polyurethane Covers for Helicopters", Vertiflite, vol. 23, No. 3, May-Jun. 1977, p. 11. |
| "Aerospatiale's Twin Squirrel . . . ", Flight International, 13 Sep., 1980, photo on p. 1973. |