UnScramble this Word: t n i g c h c a?

Questions

What type of plane did buddy holly, the big bopper, & richie valens die?

What U S state song is named for a river within the state?

What U.S. classical conductor won posthumous Grammy Awards in 1991, 1992, & 1993?

what u.s. state was used for the location shots for the 1955 hit musical oklahoma?

what was beethoven's first name?