R11, R-11, or similar, may refer to:* R-11 (missile), a Scud tactical ballistic missile model R11 (New York City Subway car) , a risk phrase Caudron R.11, a French escort biplane fighter aircraft used during World War I Principe de Asturias (R11), a Spanish aircraft carrier Renault 11, a 1981 small family car USS R-11 (SS-88), a 1919 R-class coastal and harbor defense submarine of the United States Navy Erre XI, a reggaetón duo from Puerto Rico and also : A thermal insulating value… (More on R-11)