| Clue | Source | Date |
|---|---|---|
| Ironing out source of disagreement in description of airship | ||
| Flexible, like the envelope of some airships | ||
| Flexible | The Times Concise | 06 Jul 2022 |
| Flexible | Wall Street Journal | 15 May 2021 |
| Flexible | Family Time | 24 Jun 2019 |
| Flexible | New York Times | 17 Dec 2015 |
| Flexible | ||
| Lacking firmness |