For this, the authors developed an index of wing damage (Wing Damage Index, WDI) divided into 4 categories, allant the 0 (no damage) to 3 (major damage). The details of this classification can be found in the article that you can get by clicking here.
Kwa hii, waandishi maendeleo index ya uharibifu mrengo (Mrengo Uharibifu Index, WDI) kugawanywa katika 4 makundi, Allanti ya 0 (hakuna uharibifu) kwa 3 (makubwa ya uharibifu).