Which of the following correctly lists the two dope types used for fabric finishes?

• A. Cellulose Nitrate and Cellulose Acetate Butyrate
• B. Epoxy and Vinyl
• C. Nylon and Polyester
• D. Acrylic and Polyurethane

Answer: (A)

Dopes for fabric finishes are coatings applied to the fabric covering of an aircraft to shrink and tighten the fabric, forming a tough, weather-resistant skin. The two types used historically are cellulose nitrate (nitrocellulose) and cellulose acetate butyrate. Nitrocellulose dope tightens the fabric as it dries, providing a strong, hard film, but it is highly flammable. Cellulose acetate butyrate dope offers similar protective properties with greater flexibility and lower flammability, helping to resist cracking with temperature changes. Because these two materials are the classic dopes specifically formulated for fabric finishing, they’re the correct pairing. The other options refer to different resins or materials not used as the standard fabric dopes for this purpose.