ABSTRACT
Canopy transparencies become scratched, pitted, or otherwise damaged during their service life on aircraft through a number of mechanisms. While it would seem that contact by objects during flight might be a major source, in reality such strikes from objects of substantial size are rare and usually cause irreparable damage. Instead, the types of damage requiring rework fall under the category of normal deterioration while in service: wind-blown sand while parked on the ground gradually reduces clarity, fine abrasives in the air while in flight cause hazing, contact on external surfaces due to maintenance crew carelessness causes scratches and pits, contact on interior surfaces by pilot helmets and clipboards produces predictable damage to the transparency.
